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Title: Ringing Out
Post by: Bob Burke on June 24, 2014, 10:25:35 am
Hello all. I have stupid question #236  ;D  to ask regarding ringing out a small rig.

I have a Soundcraft EFX8 that I love:

http://www.soundcraft.com/products/product.aspx?pid=148


and a dbx 1231:

http://dbxpro.com/en-US/products/1231.


  My normal procedure is to set my GEQ flat, then adjust my channel strips EQs to where I want them. Then I bring up the master faders to look for squealing freqs, which I then cut on the dbx. Is this the proper method to use?

  Invariably, I end up cutting some frequencies on the dbx that I really need - for vocal clarity, for instance. Then I try to compensate by raising the high EQ on the channel strip – bad, I know.

  I have read tons of articles about this, but I find that in real world practice (especially in a horribly reflective space), I'm not getting the results I want.

  I'm not dealing with a lot of sources – two vocal mics and two channels of backing tracks, and we're not silly loud. I just want as much GBF I can get without any possibility of a feedback disaster in the middle of a song!

  Can you straighten this out for me?



Thanks.


Bob

 
Title: Re: Ringing Out
Post by: DavidTurner on June 24, 2014, 10:55:54 am
Although this is not how I would do it, I'm going to go out on a limb here and say if this gives you the results you want, it is the proper way for YOU.


Hello all. I have stupid question #236  ;D  to ask regarding ringing out a small rig.

I have a Soundcraft EFX8 that I love:

http://www.soundcraft.com/products/product.aspx?pid=148


and a dbx 1231:

http://dbxpro.com/en-US/products/1231.


  My normal procedure is to set my GEQ flat, then adjust my channel strips EQs to where I want them. Then I bring up the master faders to look for squealing freqs, which I then cut on the dbx. Is this the proper method to use?

  Invariably, I end up cutting some frequencies on the dbx that I really need - for vocal clarity, for instance. Then I try to compensate by raising the high EQ on the channel strip – bad, I know.

  I have read tons of articles about this, but I find that in real world practice (especially in a horribly reflective space), I'm not getting the results I want.

  I'm not dealing with a lot of sources – two vocal mics and two channels of backing tracks, and we're not silly loud. I just want as much GBF I can get without any possibility of a feedback disaster in the middle of a song!

  Can you straighten this out for me?



Thanks.


Bob

 
Title: Re: Ringing Out
Post by: Bob Burke on June 24, 2014, 10:57:41 am
Mr. Turner,

  Actually, it's not giving me the results I want. Hence the question. How do you do it? (bear in mind, I don't have a driverack).

Thanks.

Bob
Title: Re: Ringing Out
Post by: Art Welter on June 24, 2014, 11:25:56 am
My normal procedure is to set my GEQ flat, then adjust my channel strips EQs to where I want them. Then I bring up the master faders to look for squealing freqs, which I then cut on the dbx. Is this the proper method to use?

  Invariably, I end up cutting some frequencies on the dbx that I really need - for vocal clarity, for instance. Then I try to compensate by raising the high EQ on the channel strip – bad, I know.

  I have read tons of articles about this, but I find that in real world practice (especially in a horribly reflective space), I'm not getting the results I want.
Bob,

In a horribly reflective place to get good results requires putting the sound where you want it, and keeping it away from where you don't.
Are your speakers above head height and angled down to the listeners?
What is their coverage pattern?
"Squealing" (high frequency feedback) sounds like your vocal mics are in the coverage pattern of the mains. Are you attempting to use the mains for monitors also?
Have you tried using in ear monitors (which can be as simple as using some ear buds from the headphone output of your mixer)?

Art
Title: Re: Ringing Out
Post by: Keith Billik on June 24, 2014, 11:30:14 am
Hello all. I have stupid question #236  ;D  to ask regarding ringing out a small rig.

I have a Soundcraft EFX8 that I love:

http://www.soundcraft.com/products/product.aspx?pid=148


and a dbx 1231:

http://dbxpro.com/en-US/products/1231.


  My normal procedure is to set my GEQ flat, then adjust my channel strips EQs to where I want them. Then I bring up the master faders to look for squealing freqs, which I then cut on the dbx. Is this the proper method to use?

  Invariably, I end up cutting some frequencies on the dbx that I really need - for vocal clarity, for instance. Then I try to compensate by raising the high EQ on the channel strip – bad, I know.

  I have read tons of articles about this, but I find that in real world practice (especially in a horribly reflective space), I'm not getting the results I want.

  I'm not dealing with a lot of sources – two vocal mics and two channels of backing tracks, and we're not silly loud. I just want as much GBF I can get without any possibility of a feedback disaster in the middle of a song!

  Can you straighten this out for me?



Thanks.


Bob

 

Here are a couple thoughts:

- Your method seems fine, that is basically what I do. However, how many cuts are you making? After you make 3 or 4 cuts in the EQ, you are kind of fighting against yourself (in other words, that's as good as it's gonna get).

- High EQ normally is way above what I would consider "vocal clarity," so I'm not sure what you have going on there, but that may be part of the problem.

- If you are lacking vocal clarity, you may want to try to cut those frequencies from your tracks, instead of boosting them on the vocals. Depending on the voice, this will be somewhere in the 2k-5k area.

- Another idea: since you only have 2 open microphones, you could insert each channel of your dbx on those two channels, and have a complete 31-band EQ for each mic. Since each one may demand different settings, this may help you get the most out of them.
Title: Re: Ringing Out
Post by: Bob Burke on June 24, 2014, 12:04:54 pm
Bob,

In a horribly reflective place to get good results requires putting the sound where you want it, and keeping it away from where you don't.
Are your speakers above head height and angled down to the listeners?
What is their coverage pattern?
"Squealing" (high frequency feedback) sounds like your vocal mics are in the coverage pattern of the mains. Are you attempting to use the mains for monitors also?
Have you tried using in ear monitors (which can be as simple as using some ear buds from the headphone output of your mixer)?

Art



Hi Art. We're using Yammy 115V's for mains, behind us (Bob Leonard's method), and have only tried this once or twice. It works pretty well. I'm using the cheap CAD189 dynamics, which have great GBF. I usually use Beta 87A's, which I prefer, but they are really hot mics. Monitors right now are Peavey PR-12 (which I hate and am returning - to be replaced with Yammy CM12Vs.)

  I can get acceptable levels, I just want to see if I can improve my system.


Regards,

Bob


(http://i40.photobucket.com/albums/e222/DunnellonOnline/Setup.jpg) (http://s40.photobucket.com/user/DunnellonOnline/media/Setup.jpg.html)
Title: Re: Ringing Out
Post by: Bob Burke on June 24, 2014, 12:07:45 pm
Here are a couple thoughts:

- Your method seems fine, that is basically what I do. However, how many cuts are you making? After you make 3 or 4 cuts in the EQ, you are kind of fighting against yourself (in other words, that's as good as it's gonna get).

- High EQ normally is way above what I would consider "vocal clarity," so I'm not sure what you have going on there, but that may be part of the problem.

- If you are lacking vocal clarity, you may want to try to cut those frequencies from your tracks, instead of boosting them on the vocals. Depending on the voice, this will be somewhere in the 2k-5k area.

- Another idea: since you only have 2 open microphones, you could insert each channel of your dbx on those two channels, and have a complete 31-band EQ for each mic. Since each one may demand different settings, this may help you get the most out of them.


Keith,

  I know I'm making too many cuts. I'm a musician, not a sound man. ;D

I am currently using one side of the dbx for the mains, and the other for the monitors.


Regards,

Bob
Title: Re: Ringing Out
Post by: Tim McCulloch on June 24, 2014, 12:22:25 pm
Bob, the biggest problem I see with your method is pre-emptive channel strip EQ.  Other that setting a high pass on vocals and some instruments I know I'll use them on (acoustic gtr, mandolins, etc), I don't cut much and I *never* boost a freq band before I've heard the system, tuned the system, and then listen to each input to make voicing changes on the channel strip EQ.

I think you need to tune the rig so it sounds 'right' with a decently broad selection of recorded material germane to your performance.  Then you need to ring the monitors/PA, and only then voice the inputs.  Why?  Because if you do it your current way, you can't tell if the problem is speaker/mic placement, some oddity of system response, a peaky mic, or your pre-emptive EQ based on not hearing the system...

After looking at the picture, I also think you can safely leave one of the monitors at home.  The comb filtering from the pair (I'm presuming it's one mix, or that there are identical signals within 6dB in each speaker) is making your life difficult.  Moving your head even an inch or 2 will result in vastly different tonality, and if you try to "correct" that with EQ you're chasing ferrets thru a fun house AND creating further problems that you will perceive differently every time you move your head.  Really.  The alternative is to move them much further apart, but it doesn't look like you have the space to do that.

And while most folks will tell you to never put the PA behind the mics, my *experience* is that it can be done.  I routinely have corporate presenters wearing lavalier mics downstage of the PA (often they work the audience) in hotel ballrooms and meeting spaces.  I'm not suggesting that this is without potential peril and I'm not saying that just anyone can do this and get acceptable results the first time, but yes Virginia, you CAN put the PA upstage if you take the time to experiment away from a gig situation and its attendant pressures.

And my main finding, after years of making my own mistakes and watching other folks make their own mistakes... most of the time the mixer operator gets hung up on "unity."  I'd love to turn back the clock and remove that bit of Mackie marketing-speak.  It results in most operators sending too-hot of a signal to the amps, and they have a wall of feedback if they move a fader or knob more than 20% of travel.  Think about it like this, you're adding 30dB or more gain at the mixer, and another 32dB or possibly more at the amp.  You might need about 40dB of gain total, but, following the Mackie bullshit, you've added over 60dB.  Bob, this isn't aimed specifically at you, but I post it to address an issue I find all too often.

Have fun, good luck.

Tim Mc
Title: Re: Ringing Out
Post by: Bob Leonard on June 24, 2014, 12:32:53 pm
Bob,
Your picture tells the story I need to hear.

If you're using the EQ as a system EQ (IN LINE with the main output)the goal is to adjust that EQ so that system response is flat, and then leave it alone. This can be done at a practice session before the gig. From that point the board channel strip is what should be used for individual changes to the voice or instrument running through that channel. If the channel strip isn't enough then add an EQ for that particular channel and work with that, not the system EQ.

Looking at the rig in the picture it's apparent you work smaller clubs and gigs with your duo. You have enough amplification behind you for guitars, and with the FOH cabinets behind you, something I do quite often, you may find you either don't need monitors, or that you don't need much volume from them. So what comes from front of house? Vocals pretty much.

Here's a very old school trick. Turn off the monitors, set the board EQ's all flat, and using the system EQ set the FOH to sound it's best using recorded but not compressed material, or while someone sings. Again, this can be done at home. This isn't exactly the right way to set the system, but it works and gives you a base line to work from. When you get to the club use the channel EQ's, not the system EQ to set the tone for the channel.

For the monitors use an EQ for each monitor and adjust them to taste separately. I might also suggest that you angle the monitor more towards the side of the mic and further away from each other.
Title: Re: Ringing Out
Post by: Bob Leonard on June 24, 2014, 12:34:10 pm
Tim,
You just had to beat me to the post.
Title: Re: Ringing Out
Post by: Steve M Smith on June 24, 2014, 12:37:08 pm
I would never presume to know what the EQ settings will be and will always start with the EQ flat.  Usually cutting four or five frequencies a bit is enough to tame the resonances in a room.

Think of the graphic EQ as a method to match the system to the room.  Once you have done that, just use the channel EQ to make any changes you want to individual inputs.


Steve.
Title: Re: Ringing Out
Post by: Bob Leonard on June 24, 2014, 12:41:47 pm
I would never presume to know what the EQ settings will be and will always start with the EQ flat.  Usually cutting four or five frequencies a bit is enough to tame the resonances in a room.

Think of the graphic EQ as a method to match the system to the room.  Once you have done that, just use the channel EQ to make any changes you want to individual inputs.


Steve.

My system EQ is a combination of my DR 4800 and a touch of the Expression output EQ. I haven't need to touch the system EQ in more than 2 years. Everything needed for the room can be handled quite well using the channel strip EQ.
Title: Re: Ringing Out
Post by: Art Welter on June 24, 2014, 12:43:26 pm


Hi Art. We're using Yammy 115V's for mains, behind us (Bob Leonard's method), and have only tried this once or twice.
 I can get acceptable levels, I just want to see if I can improve my system.
Bob,

Putting the speakers behind the mics as you have done should eliminate the need for monitors, but makes the mics prone to HF feedback. From what I understood from Bob L., and my own experience, the mains can be placed in a flanking position and still cover you and the audience OK, but in the position you show as soon as your head is not between the mains and the mic, it will feed back if you are using more than moderate gain.

Your mains are more focused at the mics than your monitors, if you want to use both, prop the monitors up so you are looking down the center of the horn, and move your mains so you are out of their coverage pattern. Monitors work because they face the "dead" side of the cardioid mic pick up pattern, you can't expect as much gain from the mains when they are on the side of the mic that hears well.

That said, skip the monitors, put the mains out of the mic pickup pattern and use some in ear monitors and your feedback and intelligibility problems will be gone.

Art
Title: Re: Ringing Out
Post by: Steve Oldridge on June 24, 2014, 01:27:12 pm
Monitors right now are Peavey PR-12 (which I hate and am returning - to be replaced with Yammy CM12Vs.)
 

Bob, looking at your pic, if you place monitors on the floor like that, it probably won't change your experience by going with CM12V's...   monitors are directional by design and you will hear them better if they are pointing at your head and not your knees. :)
Title: Re: Ringing Out
Post by: lindsay Dean on June 24, 2014, 01:36:40 pm
Bob,

Putting the speakers behind the mics as you have done should eliminate the need for monitors, but makes the mics prone to HF feedback. From what I understood from Bob L., and my own experience, the mains can be placed in a flanking position and still cover you and the audience OK, but in the position you show as soon as your head is not between the mains and the mic, it will feed back if you are using more than moderate gain.

Your mains are more focused at the mics than your monitors, if you want to use both, prop the monitors up so you are looking down the center of the horn, and move your mains so you are out of their coverage pattern. Monitors work because they face the "dead" side of the cardioid mic pick up pattern, you can't expect as much gain from the mains when they are on the side of the mic that hears well.

That said, skip the monitors, put the mains out of the mic pickup pattern and use some in ear monitors and your feedback and intelligibility problems will be gone.

Art

The mains behind the mic line can be a problem depending on the pattern.  The sound will be picked up by the mics and reproduced through the mon and mains, then arriving at your ears at different times causing an odd phase cancellation thing that you will try to adjust , not fun! my recomendations would be,
1.Use good quality cardiod mics,cheap or mismatched vocal mics can wreak havoc on monitor eq , get the strips set on all instrument/ vocals /tracks the way you like through a set of over the ear reference head phones you prefer
2. Get the mains forward of the mic line is best, or as far to each side as possible in the center of each wall behind you
3. Guitar amps  mic's vocal mics etc. are set up the same everytime.
4. Gain structure , ive seen main out on mixers way up channel strips down , not good .
 
 The only thing to change Is the main / mon eq to suit each room. you will chase your tail constantly if your adjusting channels and main eq,s to get it
Title: Re: Ringing Out
Post by: Scott Olewiler on June 24, 2014, 04:09:49 pm
One thing no one's mentioned is your mic preamps. If they're too hot you're much more susceptible to feedback. You don't need you trim/gain/pre-amp cranked to get decent sound out of your mics if you've got some headroom in the system elsewhere.  I'm also of the mindset that you really shouldn't have to do much of anything with your channel strip eq other than  rolling off your lows if you don't have an adequate HPF.  Mine remain at 12 oclock almost 100% of the time for every channel. Making changes there before EQing the system is a recipe for disaster. 
Title: Re: Ringing Out
Post by: g'bye, Dick Rees on June 24, 2014, 04:17:51 pm
One thing no one's mentioned is your mic preamps. If they're too hot you're much more susceptible to feedback. You don't need you trim/gain/pre-amp cranked to get decent sound out of your mics if you've got some headroom in the system elsewhere.  I'm also of the mindset that you really shouldn't have to do much of anything with your channel strip eq other than  rolling off your lows if you don't have an adequate HPF.  Mine remain at 12 oclock almost 100% of the time for every channel. Making changes there before EQing the system is a recipe for disaster.

Nope.  Sorry, but it's overall system gain and it matters not where you get it regarding the threshold of feedback. 

You can run your pre's hot or cold, but you'll just end up running something else cold or hot to compensate.  Set your input gains properly such that the distance from the noise floor is as equal as possible at every device and point of adjusment in the signal chain.
Title: Re: Ringing Out
Post by: Mike Kirby on June 24, 2014, 07:50:54 pm
I may be missing something here but are the system EQ's not used to tune the room and the discrepancies in the cabinets themselves?? No cabinet will be flat unless it comes with its own processor that will have notch filters built in to adjust the resonant frequencies out of the cabinets, even with a processor it would be very hard to come accross a completely flat room. In my humble opinion you should always tune the system first with a vocal mic to get an idea of what the room is doing then run some good quality well produced music through to further tune the system, once the sytem is as close to flat as you can get it then use the desk eq's to tune each line.......my next peice of advise is pretty much the same as Tim has said, dont be scared to cut frequencies to reach your objective after all isnt that why the eq has the ability to cut in the first place???? if you have a gain loss due to cutting frequencies this can be made up through the desk, compressor or crossover output stages.....usually a little bit added to each will assure a cleaner signal path unless you are using high end compressors such as Aphex Compellor/Dominator or such....................of course using a program such as SI Smaart or another RTA program on a laptop would make life easier but not necessary.

I tend to run my inputs quite low, the reason for this is to eliminate spill from intruments/monitors..........if you look at it sensibly the more you increase the gain on a mic the more area that mic will pick up and the objective is to keep that area as small as possible then build the gain up through the desk and if necessary boost via your outboard gear, I find this creates more AIR in the mix so it is easier to just place your instruments/Vocals where you want them giving a much fuller and cleaner sound.
Title: Re: Ringing Out
Post by: Tim McCulloch on June 24, 2014, 07:58:00 pm
I may be missing something here but are the system EQ's not used to tune the room and the discrepancies in the cabinets themselves?? No cabinet will be flat unless it comes with its own processor that will have notch filters built in to adjust the resonant frequencies out of the cabinets, even with a processor it would be very hard to come accross a completely flat room. In my humble opinion you should always tune the system first with a vocal mic to get an idea of what the room is doing then run some good quality well produced music through to further tune the system, once the sytem is as close to flat as you can get it then use the desk eq's to tune each line.......my next peice of advise is pretty much the same as Tim has said, dont be scared to cut frequencies to reach your objective after all isnt that why the eq has the ability to cut in the first place???? if you have a gain loss due to cutting frequencies this can be made up through the desk, compressor or crossover output stages.....usually a little bit added to each will assure a cleaner signal path unless you are using high end compressors such as Aphex Compellor/Dominator or such...................of course using a program such as SI Smaart or another RTA program on a laptop would make life easier but not necessary

The only EQ that can "tune" a room is the D9 EQ.  It can flatten things in a hurry.

/nudge, wink
Title: Re: Ringing Out
Post by: Mike Kirby on June 24, 2014, 08:08:36 pm
The only EQ that can "tune" a room is the D9 EQ.  It can flatten things in a hurry.

/nudge, wink

I love my White 4500's :)  I have been tuning by ear for quite sometime so it is not difficult for me but I do understand that trying to find the right harmonic for some would be quite difficult so a self tuning eq or a driverack would be easier.
Title: Re: Ringing Out
Post by: g'bye, Dick Rees on June 24, 2014, 08:10:39 pm
I may be missing something here but are the system EQ's not used to tune the room and the discrepancies in the cabinets themselves?? No cabinet will be flat unless it comes with its own processor that will have notch filters built in to adjust the resonant frequencies out of the cabinets, even with a processor it would be very hard to come accross a completely flat room. In my humble opinion you should always tune the system first with a vocal mic to get an idea of what the room is doing then run some good quality well produced music through to further tune the system, once the sytem is as close to flat as you can get it then use the desk eq's to tune each line.......my next peice of advise is pretty much the same as Tim has said, dont be scared to cut frequencies to reach your objective after all isnt that why the eq has the ability to cut in the first place???? if you have a gain loss due to cutting frequencies this can be made up through the desk, compressor or crossover output stages.....usually a little bit added to each will assure a cleaner signal path unless you are using high end compressors such as Aphex Compellor/Dominator or such...................of course using a program such as SI Smaart or another RTA program on a laptop would make life easier but not necessary

With a single open mic out in the sound field, a GEQ/PEQ rack and 15-20 minutes of undisturbed working time it is possible to eliminate the worst of the offending room/system interactions with filters narrow enough that bypassing the PEQ will give no audible difference in a full-spectrum program of music.

I use the GEQ to initially identify the hot spots, then replace the cuts with surgically narrowed PEQ filters.  I restore the GEQ to flat for tonal trim use during the show.
Title: Re: Ringing Out
Post by: Bob Leonard on June 24, 2014, 08:37:19 pm
D9, exactly.

@ All - The system EQ is set once for the system, not the room. Once the system has been set flat to the best of your ability you have tuned the system. If you have Smaart then fine, if you don't then see above. And this is the LOUNGE, so let's help the newbie's with little experience in a practical way.

MYTH - You don't have to tune the system for every room you enter. Once you've set the system EQ, for general purpose use if you like, it now becomes an exercise in futility to change the system response because you don't like the sound of the kick drum or particular vocal channel in another room. What you're doing at that point is telling yourself you don't like the sound of a particular instrument or mic and re-setting the entire system to accommodate that one device. Use the channel strip EQ first, then if that fails or your board sucks, then go ahead and make minor adjustments, MINOR, to the system EQ, and when you leave set the EQ back to where it was before you started.

I said nothing about monitors, but agree with what has been said. Point them at your face, not your knee caps.

Once you've set the system EQ and your system sounds as good as it can then a minor change may become applicable if the channel strip won't do the job, but how could you possibly know if your first step is to set the system EQ, the system you tuned for general purpose use, flat, removing your baseline settings. Leave the system EQ alone unless you have a very bad problem, don't flatten it for every room, minor changes if the channel strip EQ won't do the job, channel strip EQ first.
Title: Re: Ringing Out
Post by: g'bye, Dick Rees on June 24, 2014, 08:42:25 pm
Sorry.  My reply just above Bobs was addressing issues other than system EQ...or as usually stated, DSP.  Once your DSP is set, your other EQ will be effective.  Without system tuning via DSP, your other EQ adjustments are less effective in getting the results desired.
Title: Re: Ringing Out
Post by: jasonfinnigan on June 24, 2014, 08:44:36 pm
D9, exactly.

@ All - The system EQ is set once for the system, not the room. Once the system has been set flat to the best of your ability you have tuned the system. If you have Smaart then fine, if you don't then see above. And this is the LOUNGE, so let's help the newbie's with little experience in a practical way.

Depends on what your calling the system EQ. IMO the DSP/Speaker processing should be used to tune the gear to each other. Your 31 band eq's outboard or on a digital console should be used for room tuning or adjustments for personal taste.
Title: Re: Ringing Out
Post by: Mike Kirby on June 24, 2014, 08:45:30 pm
D9, exactly.

@ All - The system EQ is set once for the system, not the room. Once the system has been set flat to the best of your ability you have tuned the system. If you have Smaart then fine, if you don't then see above. And this is the LOUNGE, so let's help the newbie's with little experience in a practical way.

MYTH - You don't have to tune the system for every room you enter. Once you've set the system EQ, for general purpose use if you like, it now becomes an exercise in futility to change the system response because you don't like the sound of the kick drum or particular vocal channel in another room. What you're doing at that point is telling yourself you don't like the sound of a particular instrument or mic and re-setting the entire system to accommodate that one device. Use the channel strip EQ first, then if that fails or your board sucks, then go ahead and make minor adjustments, MINOR, to the system EQ, and when you leave set the EQ back to where it was before you started.

I said nothing about monitors, but agree with what has been said. Point them at your face, not your knee caps.

Once you've set the system EQ and your system sounds as good as it can then a minor change may become applicable if the channel strip won't do the job, but how could you possibly know if your first step is to set the system EQ, the system you tuned for general purpose use, flat, removing your baseline settings. Leave the system EQ alone unless you have a very bad problem, don't flatten it for every room, minor changes if the channel strip EQ won't do the job, channel strip EQ first.

Agreed, some changes are necessary if the room is overly live such as a concrete and glass box but mostly the system Eq's do not change much.
Title: Re: Ringing Out
Post by: Mike Kirby on June 24, 2014, 09:49:12 pm
Depends on what your calling the system EQ. IMO the DSP/Speaker processing should be used to tune the gear to each other. Your 31 band eq's outboard or on a digital console should be used for room tuning or adjustments for personal taste.

I suppose it boils down to personal taste really, I personaly use a Yamaha DME 8iC and Yamaha DME 8oC as my crossovers and notch filter however I still use Passive White 4500's for FOH EQ and an Aphex 320D Compellor and 723 Dominator coupled with a Midas Siena 48/16......but thats just me I like mixing anologue and digital because I just love the Anologue warmth. :)
Title: Re: Ringing Out
Post by: Bob Leonard on June 24, 2014, 09:59:24 pm
Sorry.  My reply just above Bobs was addressing issues other than system EQ...or as usually stated, DSP.  Once your DSP is set, your other EQ will be effective.  Without system tuning via DSP, your other EQ adjustments are less effective in getting the results desired.

We're saying the same thing Dick.
Title: Re: Ringing Out
Post by: Blake Short on June 24, 2014, 11:47:18 pm
D9, exactly.

@ All - The system EQ is set once for the system, not the room. Once the system has been set flat to the best of your ability you have tuned the system. If you have Smaart then fine, if you don't then see above. And this is the LOUNGE, so let's help the newbie's with little experience in a practical way.

MYTH - You don't have to tune the system for every room you enter. Once you've set the system EQ, for general purpose use if you like, it now becomes an exercise in futility to change the system response because you don't like the sound of the kick drum or particular vocal channel in another room. What you're doing at that point is telling yourself you don't like the sound of a particular instrument or mic and re-setting the entire system to accommodate that one device. Use the channel strip EQ first, then if that fails or your board sucks, then go ahead and make minor adjustments, MINOR, to the system EQ, and when you leave set the EQ back to where it was before you started.

I said nothing about monitors, but agree with what has been said. Point them at your face, not your knee caps.

Once you've set the system EQ and your system sounds as good as it can then a minor change may become applicable if the channel strip won't do the job, but how could you possibly know if your first step is to set the system EQ, the system you tuned for general purpose use, flat, removing your baseline settings. Leave the system EQ alone unless you have a very bad problem, don't flatten it for every room, minor changes if the channel strip EQ won't do the job, channel strip EQ first.

Bob thanks for posting this bit of advice... i'm new to running sound on my new prosonus 16.4.2AI and this post makes a ton of sense to me.  So I'm thinking about tuning my system in my garage... it's about 25x25ish, should be enough room to get sensible results?  Also i'll be doing the tuning with the 31 band in the board, using the "bump" method to ring out the cabinets.  JBL JRX115s.  Does this seem to be the direction i need to be heading to get this system tuned.  Also, do i set the channel strip settings all to unity for the mic i will be using to tune the system?
Title: Re: Ringing Out
Post by: g'bye, Dick Rees on June 25, 2014, 12:02:57 am
Bob thanks for posting this bit of advice... i'm new to running sound on my new prosonus 16.4.2AI and this post makes a ton of sense to me.  So I'm thinking about tuning my system in my garage... it's about 25x25ish, should be enough room to get sensible results?  Also i'll be doing the tuning with the 31 band in the board, using the "bump" method to ring out the cabinets.  JBL JRX115s.  Does this seem to be the direction i need to be heading to get this system tuned.  Also, do i set the channel strip settings all to unity for the mic i will be using to tune the system?

Blake...

There's been a bit of confusion of terms here.  "System EQ" is not generally done with a GEQ, but rather, involves using the PEQ (and in some cases alignment delay) as well as setting the drive levels for the various boxes in the system such as subs/tops or any bi- or tri- amped boxes.  All this is generally done with a DSP.

You  can then use your GEQ for overall tone sculpting of your mix.

So really there are two different things her:

1.  System tuning with DSP...remaining constant from venue to venue and...

2.   Mains EQ using a 31 band GEQ...adjusted to taste for the venue/mix du jour.
Title: Re: Ringing Out
Post by: jasonfinnigan on June 25, 2014, 12:24:28 am

So really there are two different things her:

1.  System tuning with DSP...remaining constant from venue to venue and...

2.   Mains EQ using a 31 band GEQ...adjusted to taste for the venue/mix du jour.

+1 exactly the way it should be done.
Title: Re: Ringing Out
Post by: Bob Leonard on June 25, 2014, 12:40:52 am
Blake...

There's been a bit of confusion of terms here.  "System EQ" is not generally done with a GEQ, but rather, involves using the PEQ (and in some cases alignment delay) as well as setting the drive levels for the various boxes in the system such as subs/tops or any bi- or tri- amped boxes.  All this is generally done with a DSP.

You  can then use your GEQ for overall tone sculpting of your mix.

So really there are two different things her:

1.  System tuning with DSP...remaining constant from venue to venue and...

2.   Mains EQ using a 31 band GEQ...adjusted to taste for the venue/mix du jour.

Exactly, and to simplify further the OP doesn't have a DSP as far as I know (drive rack, etc.) that has an EQ he can use for the system so he'll be using an EQ in line with the main outputs (L/R) in place of the DSP. In the OP's case it doesn't matter if the EQ is a PEQ or GEQ, what matters is what Dick and I are saying, set it and pretty much forget it.
Title: Re: Ringing Out
Post by: Mike Kirby on June 25, 2014, 02:22:53 am
That was my next question. What if you do not use a DSP or have any digital equipment?? I started out with crappy EQ's, xovers and compressors with roys, 45/60's, 2445 horns and ACT subs. Multi cores made from 20 strands of crappy mic cable, so you soon learn to improvise and adapt to get the end result you want. In cases like this all you have is desk-->EQ's--->compressors--->Xovers then straight to the amps, and when you are using and old peavey 1200 desk or a 2404 you dont have a lot of desk eq options so you tend to become creative with what you have ;)
Title: Re: Ringing Out
Post by: Steve M Smith on June 25, 2014, 03:03:35 am
That was my next question..........

so you tend to become creative with what you have ;)

You just answered your own question!


Steve.
Title: Re: Ringing Out
Post by: Scott Olewiler on June 25, 2014, 04:02:29 am
Nope.  Sorry, but it's overall system gain and it matters not where you get it regarding the threshold of feedback. 

You can run your pre's hot or cold, but you'll just end up running something else cold or hot to compensate.  Set your input gains properly such that the distance from the noise floor is as equal as possible at every device and point of adjusment in the signal chain.

So you're saying that if I have 2 indentical mics on 2 channels, one that has the pre-amp set at a reasonable level and the other is turned all the way up to where it's clipping with any input; that I can get the same overall GBF from both channels?  Same actual speaker output? The clipping channel will not feedback at a lower volume?   
 I will test that out myself.
Title: Re: Ringing Out
Post by: Steve M Smith on June 25, 2014, 04:41:37 am
Correct.  In much the same way as both 2x6 and 6x2 = 12.


Steve.
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 06:32:42 am
  I'm very grateful for all the replies and advice. I realize now that I have been doing quite a bit wrong. I don't have a DSP, just a small analog mixer, a 31 band dbx GEQ, a QSC PLX1804 and a pair of Yammy 4115s.

  I was always under the impression (and had seen it stated often) that I should use the GEQ to ring out each room we played in. I still don't understand how setting my “system EQ” in my living room will translate to the VFW hall we've booked for New Years' Eve, or the outdoor deck we're playing this Sunday. I know it's a simple concept to you guys, but the logic of it is evading me.

 Another thing I've been doing wrong is setting my main masters at unity gain, then bringing up my channel strips. In future I will set my channel strips at unity, then bring up the masters, correct?

  You can't imagine how grateful I am for this advice. You guys are the best!


Regards,

Bob

p.s.

  The PR-12's on the floor are out of service now. I went to return them at Guitar Satan yesterday, and they found that the HF drivers were blown. Another thing I screwed up! >:(
Title: Re: Ringing Out
Post by: Guy Luckert on June 25, 2014, 06:47:01 am
Small changes in mike and speaker placement can have big changes in gain before feedback.

listen !!

dont be afraid to turn down just a little and make music.

Good Luck
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 07:07:40 am
Small changes in mike and speaker placement can have big changes in gain before feedback.

listen !!

dont be afraid to turn down just a little and make music.

Good Luck




  I'm aware of that Guy. In reality, we are usually set up in about as much space as the average drummer occupies. Not a lot of room for adjustments. As for "turning it down", we always play at low levels (hence the name - "90 dB").

  I'm not an expert at SR, but I have been playing music live for 48 years. ;D


Regards,

Bob
Title: Re: Ringing Out
Post by: Bob Leonard on June 25, 2014, 07:21:12 am
Bob,
Don't just set the channel levels at unity and walk away. I'll keep this simple. Start by talking, yelling and singing into the mic and watch the channel strip meter for that mic. It's OK to go into the yellow at the loudest sound, but stay out of the red.

Screw the numbers and forget unity at this point, just get the channel gain correct. So remember, green and yellow are OK, red, red, go away. This can be done with the speakers off. Watch those meters once in a while during the night and reduce the channel gain if needed.
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 07:46:54 am
Bob,
Don't just set the channel levels at unity and walk away. I'll keep this simple. Start by talking, yelling and singing into the mic and watch the channel strip meter for that mic. It's OK to go into the yellow at the loudest sound, but stay out of the red.

Screw the numbers and forget unity at this point, just get the channel gain correct. So remember, green and yellow are OK, red, red, go away. This can be done with the speakers off. Watch those meters once in a while during the night and reduce the channel gain if needed.



Thanks Bob. On my mixer I would engage the PFL on that channel, then set level by the main mix meters, right? The master R/L level fader is irrelevant at this point, right?

I know....RTFM! I have, I just can't retain the information like I used to! ;D
Title: Re: Ringing Out
Post by: David Morison on June 25, 2014, 08:04:48 am
So you're saying that if I have 2 indentical mics on 2 channels, one that has the pre-amp set at a reasonable level and the other is turned all the way up to where it's clipping with any input; that I can get the same overall GBF from both channels?  Same actual speaker output? The clipping channel will not feedback at a lower volume?   
 I will test that out myself.

I'd qualify that by saying up to the point of clipping, you'll get the same results.
Clipping adds extra frequency content to the signal, so that difference could be enough to trigger feedback where it otherwise wouldn't occur.
If you do your test with one mic 5dB below clipping and the other mic 20dB below clipping, and then use the channel faders to bring them back to the same level at the desk output, then they'll exhibit exactly the same feedback sensitivity. The only difference you may notice is very slightly more background hiss on the low gain/high fader channel, but it certainly shouldn't be enough to push you noticeably nearer feedback.

HTH,
David.
Title: Re: Ringing Out
Post by: Tim McCulloch on June 25, 2014, 09:20:21 am
Bob Burke- one more time.  "Unity" is just a convenient place with a silk-screened legend and possibly a detent.  It is no more relevant than the "Normal" setting on a clothes dryer.  What is normal?  I'd say anything that isn't (based on my dryer) towels, heavy items, delicates, air fluff, freshen up and 'fast dry'.  IOW, not much is "normal"; it's a default setting if you don't have a better preference.

I'm an old analog guy, Bob.  I got my start on a Tapco 6200 and 'graduated' to BiAmp and Peavey, then Yamaha and Ramsa.  Many of the things we did back then weren't ideal from a technical POV, but we did them and mostly still do, even with digital mixers (another rant for another time).

Mythbusted #1 - Preamps are a big deal.  No, they really aren't, and John Roberts (who designed consoles and preamps in a former life) has patiently explained why in multiple posts.  But the perception that console mic pres are some kind of voodoo or *must* be operated at a particular level is wrong.  In the Olde Dayz, we'd PFL a channel and raise the input trim until the PFL meter would peak at -0- or even hit +3 on the meter.  The reason?  "It's for the preamps", we'd be told.  The result of this technique was frequently input faders somewhere down in the bottom 1/3 of their travel, but the output faders would be around the -0- mark.

Mythbusted #2 - Faders MUST be at 'unity' or -0- to work properly.  Uh.... really?  Then why make them moveable?  Nope.  Just more level, but that's a good thing, right?  Maybe yes, maybe no...

Mythbusted #3 - Amps should be run wide open.  Well, from the 'make it impossible to screw up' standpoint, running amps with no input attenuation makes sense, but it is not a requirement.  With the exception of a couple of designs not commonly used in pro audio, the input level control on an amp is a pad that results in a higher input level being needed to make the amp reach the desired operating level; the output level *capability* (potential output voltage swing) of the amp remains the same.  It was (and still is) common for amps to have an input sensitivity of around 1.4v (or half that, 0.775v), and that voltage would drive the amp to full gain output.  Interestingly, "0 dBVU" on the console corresponded to about 1.4v....  You get above 0dBVU are your amps are clipping and it's probably loud - Loud - LOUD!

Bob, all of these things conspire to make a whole lot of level, using a whole lot of electronic gain, and much of that gain isn't necessary for the quiet operation of most small portable sound systems used in casual entertainment.  The result of that brings us to:

Mythbusted #4 - If you don't have a graphic EQ, you'll never stop feedback.  The EQ is a frequency band-selective (well, sort of selective but that's for another discussion) volume control.  Considering Myths 1 -4 above, doing things the Ye Olde Way will pretty much require some kind of level reduction, and the humble graphic EQ can do just that.  I refer to such use as 'gain reduction through equalization' and that's pretty much what we did with them (and many folks still do).  When you see an EQ that has every fader from 150Hz to 8kHz down from -3 to even -12dB, this is exactly what's happening.  It would be more productive and sound better to bring down the level ahead of the EQ (mixer, at whatever stage or stages might be appropriate) and make less feedback to start with, but conventional bad advice from the Olde Dayz prevails.  That all said, having an EQ to help with tonal shaping and some feedback EQ is still a good idea, but not overdoing the amount of signal being sent to the system makes it much easier to use successfully.

Bob, I'm a big believer in acoustic solutions to acoustic problems, and if we don't put unneeded gain in the electrical signal path, we create fewer issues with the electro-acoustic interface.  If we don't put additional, unneeded sound producers in the same physical space, we reduce the amount of acoustic interference we create (the pair of monitors side by side, and the way they interfere with each other AND the PA).  That brings us to:

Mythbusted #5 - Every speaker is independent and works in its own little world.  Nope, uh uh, not even.  Think back to your high school physics class and the wave tank experiments (or you can do this at home with a baking pan, some tap water and a couple of BBs or pebbles).  You drop a pebble in the center of the tank and the water ripples in a circle, and they reflect off the sides of the tank, returning to center in interference to the first wave.  Let it get still, and simultaneously drop 2 pebbles, one in the center and the other a little off to the side, or ahead/behind.  Watch the way the ripples interact (interfere) with each other.  Now do it a few more times, changing where you drop the pebbles and observe.  Graphically this demonstrates what is happening in acoustic space when you have multiple sources that are not identically located.

There is much more, but these 5 things address most of what I see when I hear a bar band or observe many weekend warrior sound providers.

I get the biggest looks of astonishment when I'm brought in to "fix" something and wind up either turning something(s) down; turn some stuff off; or press 'bypass.'  And I give the client a full day-rate bill.

Have fun, good luck.

Tim Mc
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 10:01:30 am
Tim,

  Thanks for the detailed explanation. It's a lot of info to assimilate, but I will try. Funny you should mention the Tapco. My first mixer was a 6000R (I still have it).

  It's painfully obvious that most of my problem comes down to simple gain staging, or improper use of it. I will try to emulate your methods. As for the two monitors side by side, I thought it would work better than it did. I will be going back to my single Yamaha CM12V, (which sounds much better than the PR-12's anyway), since I succeeded in blowing the tweeters in the brand-new Peaveys. >:( The CM12V is also a dedicated monitor, with the wedge at the proper angle.

  Where do you stand on the set-it-and-forget-it technique of setting up the system and adjusting the input EQ only at the venue? That still sounds suspect to me, given the varied places that we play.

  I can't wait to put all of this great advice into practice!

Thanks again.

Regards,

Bob
Title: Re: Ringing Out
Post by: Mark McFarlane on June 25, 2014, 10:17:00 am
One argument for running channel faders 'near 0' is you may have a little more precision in small adjustments due to the non-linear behavior of some faders (e.g. at the bottom of the fader throw 1/4" = 10db but near unity 1/2"= 5db...
Title: Re: Ringing Out
Post by: Tim McCulloch on June 25, 2014, 10:25:31 am
One argument for running channel faders 'near 0' is you may have a little more precision in small adjustments due to the non-linear behavior of some faders (e.g. at the bottom of the fader throw 1/4" = 10db but near unity 1/2"= 5db...

Agreed, and most of the time that means NOT "PFLing to 0" unless the entire rig is gain-staged for that.
Title: Re: Ringing Out
Post by: John Roberts {JR} on June 25, 2014, 10:37:36 am
So you're saying that if I have 2 indentical mics on 2 channels, one that has the pre-amp set at a reasonable level and the other is turned all the way up to where it's clipping with any input; that I can get the same overall GBF from both channels?  Same actual speaker output? The clipping channel will not feedback at a lower volume?   
 I will test that out myself.

Dick Rees is correct. Yes you can get the same GBF from both but you will have to turn down the clipped channel in later stages to realize the same GBF which is related to total path gain, not just some single stage.

Turning up a gain stage past clipping does not somehow limit the gain, even though the sound will no longer get proportionately louder. The dirty little secret for why undersized amps can be associated with more feedback is that inexperienced operators can keep turning up the power amps after clipping trying to make the louder. Feedback is caused by the gain not the loudness. 

I used to make feedback on purpose for FLS demos years ago and I could easily make low powered systems feedback... it's the total path gain.

JR

PS: consoles are designed to be pretty tolerant of how the operators choose to use them. Don't over think this...
Title: Re: Ringing Out
Post by: DavidTurner on June 25, 2014, 10:49:59 am
Hi Bob:

Mr. Turner is my dad :)

I have not taken the time to read all the responses to your question so forgive me if I am repeating some other advise. No doubt you have been given some excellent pointers, but since you asked:

Looking at the picture of your rig, I would start with everything set to flat (except for a hi pass on the vocals) and adjust the mains eq  while speaking/singing into the lead vocal mic - being careful not to cut too much. Assuming that the vocal is the most important thing being amplified, I wouldn't care much about whether the rig was "flat", but whether the voice sounded good. I would then use the channel eq to make the other things being amplified sound the way I wanted.  YOur mileage may vary  ;D


 
Mr. Turner,

  Actually, it's not giving me the results I want. Hence the question. How do you do it? (bear in mind, I don't have a driverack).

Thanks.

Bob
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 10:59:02 am
Hi Bob:

Mr. Turner is my dad :)

I have not taken the time to read all the responses to your question so forgive me if I am repeating some other advise. No doubt you have been given some excellent pointers, but since you asked:

Looking at the picture of your rig, I would start with everything set to flat (except for a hi pass on the vocals) and adjust the mains eq  while speaking/singing into the lead vocal mic - being careful not to cut too much. Assuming that the vocal is the most important thing being amplified, I wouldn't care much about whether the rig was "flat", but whether the voice sounded good. I would then use the channel eq to make the other things being amplified sound the way I wanted.  YOur mileage may vary  ;D




Thanks, David. ;D

  I will govern myself accordingly.

Regards,

Bob
Title: Re: Ringing Out
Post by: Tim McCulloch on June 25, 2014, 11:10:40 am
Tim,

  Thanks for the detailed explanation. It's a lot of info to assimilate, but I will try. Funny you should mention the Tapco. My first mixer was a 6000R (I still have it).

  It's painfully obvious that most of my problem comes down to simple gain staging, or improper use of it. I will try to emulate your methods. As for the two monitors side by side, I thought it would work better than it did. I will be going back to my single Yamaha CM12V, (which sounds much better than the PR-12's anyway), since I succeeded in blowing the tweeters in the brand-new Peaveys. >:( The CM12V is also a dedicated monitor, with the wedge at the proper angle.

  Where do you stand on the set-it-and-forget-it technique of setting up the system and adjusting the input EQ only at the venue? That still sounds suspect to me, given the varied places that we play.

  I can't wait to put all of this great advice into practice!

Thanks again.

Regards,

Bob

Hi Bob-

Well, we emulate the big boys - system EQ makes the *system* work and play nice together, and "house" EQ is used to make whatever changes might be needed for that show, that day, in that room.

In the big boy world those are usually physically different devices although DSP technology has allowed us to blur those lines.  In weekend warrior/bands mixing themselves world, there is usually one EQ that does all the jobs.  Not ideal but it's pretty much how we all started and many continue to work.  Nothing wrong, inherently, but it can make things a bit confusing when you have to remember "was that -6db cut at 3k for the system or the glass atrium we played in last week?"

Here's what I'd consider:  Set your rig up in your back yard, using the spacing and relative positions you use most of the time.  Since you don't have sophisticated system control, voicing (EQing) the system to sound "right" is the starting point.  For a reality check, have your wife and a couple of friends/neighbors offer an opinion as to how the playback sounds with your material (you'll find a lot of variance, probably).  You're looking for "pretty good, on most of the songs."  You've done your system EQ, for the most part.  Note that we didn't really get into "flat" because "flat" systems sound boring; they don't have the amount of LF that we association with terms like warm or full, so I suggest voicing the rig to be compatible with your music.  If you have something odd, like a big boost at 8kHz, it's probably related to the music you're using to tune the rig; if it's uniformly this way consider "splitting the difference" between "flat" and whatever boost you think sounds good.  But in the end, remember this:  No building, wall, or open space can alter the physical and electronic composition of your *system*.  That's an important distinction.

Also note that we didn't use the monitors yet...

Now bring up your live mics and guitars... slowly.  If you get feedback before you reach a useable SPL, your next step is to figure out why.  Start by looking at channel strip EQ for a boost around the frequency that is feeding back.  None?  Then either try to raise the PA speakers, move them further downstage of your mics, etc.  If you have the channel strip EQ fairly flat to start with and very little fader movement introduces feedback, turn down the input trim until you can raise the fader to a more desired physical position.  This is where "unity" when used as a physical reference point, can be useful.  Most often, though, setting the mic pre to the unity detent and the fader to unity detent will result it the wrong amount of level (see previous post), but I digress.  If every input seems to 'take off' with ringing or feedback, you can also simply turn down the main output fader if the input trims seem rational (no red lights, PFLing shows inputs peaking at -10, etc); there is too much down stream gain.  You can turn it down at the mixer or you can turn down the amp.  When you're done with this and are happy with tonality, feedback control and over all SPL, use your phone to take close up pics of the EQ settings.  They are your "system EQ" settings and will be the baseline upon which you make other, venue-dependent changes.

At any rate the purpose of this exercise is to establish "normal" (so you can dry your clothes ;) ).  Remember that I said no building or walls or open space changes your system.  When you move this indoors you'll find 2 things:  the first is that you'll be turning the over all level down and that all the HF you didn't hear outdoors is suddenly prominent; you may also find you have either more or less very low end.  These are the results of the various boundary surface affecting the audio you hear because of reflections (back to Myth 5, both relating to multiple speakers and, in this case, to the reflections that are almost as loud as the original waveform).  You can't EQ reflections away.  You can do a couple of things, the first of which is to not "spray" the PA onto reflective surfaces by altering speaker positioning.  Flat, parallel orientations are worst, and using the speaker's nominal coverage angles to help you point the sound at the people and (to the extent possible) away from things that are reflective.  The other thing you can do is not "excite" reflections and room modes by removing (with EQ) some of the frequency content that is being reflected (see glass atrium comment above).  Note that listeners who do not hear the contribution of the reflection will still be hearing the cuts you make with the EQ.  If you need to make changes to the EQ, do it.  You have the pictures, right?

If you find yourself consistently making the same EQ changes regardless of room, consider making them permanent "indoor" settings and take pics of them.  No harm, no foul.  You have to make it work for you as consistently as possible.

You can often tell what a room is going to sound like by simply standing where you'll perform and speaking in a loud voice; you can tell about the audience area doing the same thing.  Chances are you can't do this in a restaurant, and a bar will likely be too noisy, but you can use your ears to great advantage once you get used to it with some practice.

It's time to head out to build some PA and assist the BE do his thing.  More later, after you've had a chance to get some questions based on experimenting with your setup.

Have fun, good luck.

Tim Mc
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 02:06:20 pm
Hi Bob-

Well, we emulate the big boys - system EQ makes the *system* work and play nice together, and "house" EQ is used to make whatever changes might be needed for that show, that day, in that room.

In the big boy world those are usually physically different devices although DSP technology has allowed us to blur those lines.  In weekend warrior/bands mixing themselves world, there is usually one EQ that does all the jobs.  Not ideal but it's pretty much how we all started and many continue to work.  Nothing wrong, inherently, but it can make things a bit confusing when you have to remember "was that -6db cut at 3k for the system or the glass atrium we played in last week?"

Here's what I'd consider:  Set your rig up in your back yard, using the spacing and relative positions you use most of the time.  Since you don't have sophisticated system control, voicing (EQing) the system to sound "right" is the starting point.  For a reality check, have your wife and a couple of friends/neighbors offer an opinion as to how the playback sounds with your material (you'll find a lot of variance, probably).  You're looking for "pretty good, on most of the songs."  You've done your system EQ, for the most part.  Note that we didn't really get into "flat" because "flat" systems sound boring; they don't have the amount of LF that we association with terms like warm or full, so I suggest voicing the rig to be compatible with your music.  If you have something odd, like a big boost at 8kHz, it's probably related to the music you're using to tune the rig; if it's uniformly this way consider "splitting the difference" between "flat" and whatever boost you think sounds good.  But in the end, remember this:  No building, wall, or open space can alter the physical and electronic composition of your *system*.  That's an important distinction.

Also note that we didn't use the monitors yet...

Now bring up your live mics and guitars... slowly.  If you get feedback before you reach a useable SPL, your next step is to figure out why.  Start by looking at channel strip EQ for a boost around the frequency that is feeding back.  None?  Then either try to raise the PA speakers, move them further downstage of your mics, etc.  If you have the channel strip EQ fairly flat to start with and very little fader movement introduces feedback, turn down the input trim until you can raise the fader to a more desired physical position.  This is where "unity" when used as a physical reference point, can be useful.  Most often, though, setting the mic pre to the unity detent and the fader to unity detent will result it the wrong amount of level (see previous post), but I digress.  If every input seems to 'take off' with ringing or feedback, you can also simply turn down the main output fader if the input trims seem rational (no red lights, PFLing shows inputs peaking at -10, etc); there is too much down stream gain.  You can turn it down at the mixer or you can turn down the amp.  When you're done with this and are happy with tonality, feedback control and over all SPL, use your phone to take close up pics of the EQ settings.  They are your "system EQ" settings and will be the baseline upon which you make other, venue-dependent changes.

At any rate the purpose of this exercise is to establish "normal" (so you can dry your clothes ;) ).  Remember that I said no building or walls or open space changes your system.  When you move this indoors you'll find 2 things:  the first is that you'll be turning the over all level down and that all the HF you didn't hear outdoors is suddenly prominent; you may also find you have either more or less very low end.  These are the results of the various boundary surface affecting the audio you hear because of reflections (back to Myth 5, both relating to multiple speakers and, in this case, to the reflections that are almost as loud as the original waveform).  You can't EQ reflections away.  You can do a couple of things, the first of which is to not "spray" the PA onto reflective surfaces by altering speaker positioning.  Flat, parallel orientations are worst, and using the speaker's nominal coverage angles to help you point the sound at the people and (to the extent possible) away from things that are reflective.  The other thing you can do is not "excite" reflections and room modes by removing (with EQ) some of the frequency content that is being reflected (see glass atrium comment above).  Note that listeners who do not hear the contribution of the reflection will still be hearing the cuts you make with the EQ.  If you need to make changes to the EQ, do it.  You have the pictures, right?

If you find yourself consistently making the same EQ changes regardless of room, consider making them permanent "indoor" settings and take pics of them.  No harm, no foul.  You have to make it work for you as consistently as possible.

You can often tell what a room is going to sound like by simply standing where you'll perform and speaking in a loud voice; you can tell about the audience area doing the same thing.  Chances are you can't do this in a restaurant, and a bar will likely be too noisy, but you can use your ears to great advantage once you get used to it with some practice.

It's time to head out to build some PA and assist the BE do his thing.  More later, after you've had a chance to get some questions based on experimenting with your setup.

Have fun, good luck.

Tim Mc



Wow.

  That is perhaps the best advice I've ever gotten. I had never even heard of the concept of "system EQ".

  Can't wait top try this.


Thanks a million!


Refards,

Bob
Title: Re: Ringing Out
Post by: jasonfinnigan on June 25, 2014, 02:25:17 pm
No building, wall, or open space can alter the physical and electronic composition of your *system*.
This!!!!! The only exception to this would be with new speakers you'll generally want to brake them in before tuning the system with DSP, as the cone, coil and magnet start to move better.

I usually do a lock out on the DSP to keep people from doing that, as I've had many people think OH, I just want to increase the gain of the sub woofers etc (which changes the crossover point, but that's another story.)
Title: Re: Ringing Out
Post by: Tim McCulloch on June 25, 2014, 03:20:53 pm
This!!!!! The only exception to this would be with new speakers you'll generally want to brake them in before tuning the system with DSP, as the cone, coil and magnet start to move better.

I usually do a lock out on the DSP to keep people from doing that, as I've had many people think OH, I just want to increase the gain of the sub woofers etc (which changes the crossover point, but that's another story.)

If the magnets move during break in, you done broke 'em, boy. ;)

We discussed the concept of loudspeaker break in on the Classic LAB or Sub forum a few months ago.  The eventual consensus was that any form of 'special' operation is no more beneficial than simply playing some music and that break in as a concept is not seen as a necessity by transducer engineers.

YMMV, etc.
Title: Re: Ringing Out
Post by: Bob Leonard on June 25, 2014, 04:29:26 pm
Then you didn't read my posts.
Title: Re: Ringing Out
Post by: Bob Burke on June 25, 2014, 04:55:49 pm
Then you didn't read my posts.


Bob -

I did read your posts. Thanks for the advice, it is much appreciated.


Regards,

Bob
Title: Re: Ringing Out
Post by: Mike Kirby on June 25, 2014, 04:57:08 pm
You just answered your own question!


Steve.

Sorry it was a rhetorical question :)
Title: Re: Ringing Out
Post by: John Esposito on June 27, 2014, 09:16:11 am
I have the exact same speakers and  monitors in my smaller PA setup and love them. I usually use the frequency response charts as a base to set my eq and then eq to taste from there. The PR12's have a significant dip in the eq starting at 600 Hz to 3k in their chart so I boost between 1k and 2k to bring clarity to my monitors. I also put a piece of wood under them to point them at my ears.

The Yammy's are fairly flat but again I set the eq to do a reverse of their chart to set the system flat then eq to taste. Here are the charts:

http://assets.peavey.com/literature/manuals/pr12p.pdf - see page 13

http://www.fullcompass.com/common/files/19541-s112v_en_om_d0.pdf - see page 32
Title: Re: Ringing Out
Post by: Bob Burke on June 27, 2014, 10:29:21 am
I have the exact same speakers and  monitors in my smaller PA setup and love them. I usually use the frequency response charts as a base to set my eq and then eq to taste from there. The PR12's have a significant dip in the eq starting at 600 Hz to 3k in their chart so I boost between 1k and 2k to bring clarity to my monitors. I also put a piece of wood under them to point them at my ears.

The Yammy's are fairly flat but again I set the eq to do a reverse of their chart to set the system flat then eq to taste. Here are the charts:

http://assets.peavey.com/literature/manuals/pr12p.pdf - see page 13

http://www.fullcompass.com/common/files/19541-s112v_en_om_d0.pdf - see page 32



  Thanks for the info John. I noticed the dip in the PR-12's, but hadn't looked at the chart. I will try the wood shim thing when I get the speakers back from the shop. My QSC PLX1804 puts out 800 watts at 4 ohms, and I believe that I blew up my tweeters when I daisy-chained them. >:(


Moron, no? ;D
Title: Re: Ringing Out
Post by: John Esposito on June 27, 2014, 03:21:43 pm


  Thanks for the info John. I noticed the dip in the PR-12's, but hadn't looked at the chart. I will try the wood shim thing when I get the speakers back from the shop. My QSC PLX1804 puts out 800 watts at 4 ohms, and I believe that I blew up my tweeters when I daisy-chained them. >:(


Moron, no? ;D

We've all been there at one time or another with live sound.

I think if you give the PR12's a chance by boosting those frequencies they will really come alive and you won't need to crank them that high at all. I couldn't believe the difference when I finally eq'd them correctly.
Title: Re: Ringing Out
Post by: Bob Burke on June 28, 2014, 12:47:19 pm
In re-reading this thread, I am amazed at the wealth of information and experience you gentlemen bring to the table. I am deeply in your debt.

We have an afternoon gig tomorrow in a small bar (our local), and I can't wait to try out all of these methods. Fortunately, we'll be loading in in the morning, so I'll have time to get it right. I've been doing  things wrong all along. ;D

Thanks again to all who contributed to this thread. You guys are the best!



Regards,


Bob
Title: Re: Ringing Out
Post by: Bob Leonard on June 28, 2014, 02:40:43 pm
Bob,
Not everything you do is wrong. everything you do is another step in the right direction on the path to learning how to be the best entertainer and sound provider you can be. Keep up the good work.
Title: Re: Ringing Out
Post by: Bob Burke on June 28, 2014, 05:05:35 pm
Bob,

  You have helped me a great deal. If I ever get to Boston maybe I could buy you a beer. I played in Boston once, a lifetime ago, at a place called “The Sword In The Stone”. The “dressing room” was a catwalk suspended over the boiler room! ;D



Thanks again.


Bob
Title: Re: Ringing Out
Post by: Bob Burke on June 30, 2014, 09:20:45 am
  Just a quick follow-up. Played last night, couldn't put the speakers behind us because of an overhang at the front of the stage, but used the advice given here on ringing out the system. Big difference! PFL'd my mics for good gain staging, kept my main master faders lower, left my channel strip EQ's flat, and had tons of headroom - and no feedback! ;D

  Used a single CM12V for a monitor, and my bass player complained that her vocals were too loud in the monitor! Woo-hoo! Never had that problem before. :D

  It was nice playing four sets without worrying about feedback, and the sound was great. Thanks again to all who helped.


Regards,

Bob
Title: Re: Ringing Out
Post by: Tim McCulloch on June 30, 2014, 12:31:23 pm
  Just a quick follow-up. Played last night, couldn't put the speakers behind us because of an overhang at the front of the stage, but used the advice given here on ringing out the system. Big difference! PFL'd my mics for good gain staging, kept my main master faders lower, left my channel strip EQ's flat, and had tons of headroom - and no feedback! ;D

  Used a single CM12V for a monitor, and my bass player complained that her vocals were too loud in the monitor! Woo-hoo! Never had that problem before. :D

  It was nice playing four sets without worrying about feedback, and the sound was great. Thanks again to all who helped.


Regards,

Bob

Bob-

Glad things are working out.  Keep experimenting. :)

Part of what is fun about your situation is that when I start typing a reply and say "do this, try that, listen for..." a dozen exceptions start coming to mind that negate the advice I'm about to post.  So little direct advice is universally applicable, that's why I tend to be long on concepts and short on specifics.

Musicians tend to be results-oriented when it comes to sound... if something works today, it will be done every time even if whatever the something is, is inappropriate tomorrow.  When weekend sound guys do this I call it voodoo.  It's how EQs get hacked to death, gain structure gets whacked and inadvisable loudspeaker delays become permanent.  Sometimes it's best to start over, tabula rasa.