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Title: Setting Levels on Powered Speakers
Post by: Mark Norgren on April 30, 2021, 08:13:58 am
I am a guitar player that happens to own a bunch of gear for our band.  We just set the rehearsal space up last night to get ready for summer!  I run two or four QSC KW181's and two KW153's for mains.  I've often wondered if there is a correct way to set the levels on the subs and mains.  Should they be set at the same levels, unity for both, both at 2 o'clock?  Set the subs up in deep mode?  Subs at 3 o'clock and mains at 1 o'clock?  Use the EQ on the board (Midas M32R) to bump the subs, especially outdoors.  We do not use aux fed subs.  I'm more interested the physical setting of the levels are set.  I have heard the some guys set the tops, go out front and have another guy turn up the subs and get them close, then do the rest on the board?  I get great results and have done it a few different ways, just wondering if there is a correct method into dialing the levels on the subs and mains?  TIA to the pro's out there!  I very much appreciate what you do!
Title: Re: Setting Levels on Powered Speakers
Post by: Kevin Maxwell on April 30, 2021, 09:40:49 am
I am a guitar player that happens to own a bunch of gear for our band.  We just set the rehearsal space up last night to get ready for summer!  I run two or four QSC KW181's and two KW153's for mains.  I've often wondered if there is a correct way to set the levels on the subs and mains.  Should they be set at the same levels, unity for both, both at 2 o'clock?  Set the subs up in deep mode?  Subs at 3 o'clock and mains at 1 o'clock?  Use the EQ on the board (Midas M32R) to bump the subs, especially outdoors.  We do not use aux fed subs.  I'm more interested the physical setting of the levels are set.  I have heard the some guys set the tops, go out front and have another guy turn up the subs and get them close, then do the rest on the board?  I get great results and have done it a few different ways, just wondering if there is a correct method into dialing the levels on the subs and mains?  TIA to the pro's out there!  I very much appreciate what you do!

I generally donít use powered speakers. When I setup a sound system either portable or an install I always set the power amps controls full up. I deal with setting the levels I need on the speakers in the DSP or on the Matrix sends on the mixer. The systems I am dealing with are dead quiet with no signal going thru them even with the amps full up. One of the main reasons I do this is so no one can come along and change the amps and increase the output and mess things up. They can only turn them down from where they are set, not up.

I would suggest that you use the Matrix outputs on the Midas M32r this gives you an output trim control. Then you can run the inputs on the mixer hotter without having to turn your input gains down below where it is really best to run them.

I am sorry this may not really answer your question except if the control on the speaker is basically the same as it is on a power amp in my situation I would turn them all the way up. For the reasons and using the routing stated above.
Title: Re: Setting Levels on Powered Speakers
Post by: Paul G. OBrien on April 30, 2021, 09:55:57 am
There is pretty much no right or wrong way to set the gains on powered speakers but in most cases setting them all at unity produces full output when the mixer hits +4dbu. If you want a bit more sub or a bit less top there is nothing wrong with turing one up or down a bit.
Title: Re: Setting Levels on Powered Speakers
Post by: Debbie Dunkley on April 30, 2021, 10:55:58 am
I am a guitar player that happens to own a bunch of gear for our band.  We just set the rehearsal space up last night to get ready for summer!  I run two or four QSC KW181's and two KW153's for mains.  I've often wondered if there is a correct way to set the levels on the subs and mains.  Should they be set at the same levels, unity for both, both at 2 o'clock?  Set the subs up in deep mode?  Subs at 3 o'clock and mains at 1 o'clock?  Use the EQ on the board (Midas M32R) to bump the subs, especially outdoors.  We do not use aux fed subs.  I'm more interested the physical setting of the levels are set.  I have heard the some guys set the tops, go out front and have another guy turn up the subs and get them close, then do the rest on the board?  I get great results and have done it a few different ways, just wondering if there is a correct method into dialing the levels on the subs and mains?  TIA to the pro's out there!  I very much appreciate what you do!

You'll probably need the subs turned up quite bit higher than the tops - especially when only using 1 sub/top per side. When I use one sub per side (using comparable cabs to yours), I tend to have the subs set at full and the tops around 12 O'clock  (depending on tops/subs used and type of music etc).
As you mentioned, setting the tops and adjusting the subs to taste is a good way to get a good bass line and then tweak - its all down to your ears.
Title: Re: Setting Levels on Powered Speakers
Post by: Mal Brown on April 30, 2021, 04:04:44 pm
I run the same rig as my 'middle' system.  2 153 over 4 181.   Inside I might go 153 over 181.

I start with the gains at about 2:00 clock dial on the subs.  153's at noon.

Then I run program material I am very familiar with and listen and wander and listen more.

I tweak based on what I hear.

153's can have a pretty aggressive mid so I may apply some EQ to pull that down.  One of my guys used to swear that rig sounded better with the 153's in full range ...  We never worked that rig on a show together.  I ran the 153's in the EXT Sub position and worked with that.
Title: Re: Setting Levels on Powered Speakers
Post by: Mark Norgren on May 01, 2021, 08:08:37 am
Interesting on how we all do things a bit different!  I also find that I run the subs usually hotter.  Our band also has keyboards and I find that he will hit low notes that I like to punch much like a kick.  Not sure about running the 153's at full range.  Reproducing those lows may cause phasing issues?

I find the term "Unity" gain to be confusing?  Is the Gain control linear in nature?
Title: Re: Setting Levels on Powered Speakers
Post by: Paul G. OBrien on May 01, 2021, 09:13:01 am
Not sure about running the 153's at full range.  Reproducing those lows may cause phasing issues?
Possible yes, but one of the main reasons to add subs to a system it to take the low frequency load away from the tops, this gives them more headroom and will clean up the low/mid range

I find the term "Unity" gain to be confusing?  Is the Gain control linear in nature?
Not usually it's logarithmic. An amplifier circuit can be designed in several ways, it can have a fixed gain such as when used in a preamp circuit, it can have no gain when it's just used as a buffer, or it can have variable gain when it is used as a gain control stage. In the last example  the amp can both attenuate or boost the signal depending where the gain control is set, and there is also a neutral setting where it's doing neither.. the signal that goes in comes out at the same level, that is unity(1:1) gain.
Title: Re: Setting Levels on Powered Speakers
Post by: Brian Jojade on May 01, 2021, 05:19:08 pm
There is pretty much no right or wrong way to set the gains on powered speakers

Oh, believe me, there are plenty of WRONG ways to do it.

Of course, there's no consensus on what the 'right' way is.  Each can use slightly different methods to get where they want to be.

The key factor is, have the gains turned up enough so that the signal that you are sending to the speaker can get loud enough without clipping the signal going into it. If turning the gain on the speaker up to maximum creates noise in the speaker, then turning it down might be necessary, otherwise, where you adjust the signal gain in the path doesn't matter too much these days.

My general personal preference is to plan for a strong signal (with enough headroom planned in) as far as I can get it.  This means using the final gain stage of the speaker or amp as the final level setting. If I don't need the full capacity of the system available to me, that's where I would turn it down.
Title: Re: Setting Levels on Powered Speakers
Post by: Paul G. OBrien on May 01, 2021, 08:18:05 pm
Oh, believe me, there are plenty of WRONG ways to do it.
LOL... No way it should be that hard but every time somebody makes something more idiot proof somebody else invents a better idiot.
Title: Re: Setting Levels on Powered Speakers
Post by: Scott Bolt on May 03, 2021, 07:52:20 pm
I personally like to set my speaker gains such that when my mixer is mid to low yellow band, my speakers are just starting to flicker the limit lights.
Title: Re: Setting Levels on Powered Speakers
Post by: Patrick Tracy on May 03, 2021, 08:10:29 pm
If I'm doing it by ear, I'll set up the console so the master fader's a few dB below zero and the meter is barely going over 0 dBVU, then set the tops to get the desired volume, the set the subs to match. That way there's headroom in the mixer and space on the fader to push it a bit later. Worst case, I run out of room on the console and have to nudge the speakers up a bit during the show.
Title: Re: Setting Levels on Powered Speakers
Post by: Tim McCulloch on May 03, 2021, 11:24:27 pm
I personally like to set my speaker gains such that when my mixer is mid to low yellow band, my speakers are just starting to flicker the limit lights.

That's pretty much the basics, I think, you're around -18DBFS.  There's a good thread over at Controlbooth.com currently discussing what "0 dB" means that's an interesting read. https://www.controlbooth.com/threads/midas-m32r-output-levels.48196/

Finding out how much "protection" comes with how much light flicker might be interesting to experiment with.
Title: Re: Setting Levels on Powered Speakers
Post by: Luke Geis on May 03, 2021, 11:58:43 pm
My prescription is to start at 0db or whatever the manufacturer says is unity. Then adjust as needed from there to achieve the desired balance at performance level. In most cases, you will add volume to the subs if you are doing a 1:1 ratio of tops to subs. Ultimately the goal is to have the outputs of the mixer not clip, have the volume you need from the speakers, and also not clip the speakers.
Title: Re: Setting Levels on Powered Speakers
Post by: Mark Norgren on May 04, 2021, 07:27:03 am
Very interesting discussion.  I loved the M32R article.  Minus 18db digital equals +4 db analog.  That is a perplexing statistic. 

I now use the solo button on my M32R to set the gain level on each channel.  By selecting the solo button, the gain level will show up on the right meter and allows me much more detail in setting the correct gain.  Gain structure is so critical in setting my board up properly.  All my dynamics and effects seem to respond better to a properly structured gain?  No real proof of that, just my 2 cents.  I never really push my speakers past 4 o'clock and seldom have clipping issues.
Title: Re: Setting Levels on Powered Speakers
Post by: Jordan Wolf on May 04, 2021, 09:40:31 am
I've often wondered if there is a correct way to set the levels on the subs and mains.  Should they be set at the same levels, unity for both, both at 2 o'clock?
If it's not a preconfigured system with DSP and/or amps with presets, etc., I typically start with levels all the way down.

Next, I input speech or music signal to the console, gain it up properly, and then output it.

Then, I turn up the inputs on the loudspeakers until I reach the general SPL I think (or know) I'll need with that type of material. I'll just use a simple meter or phone app - it's a relative process.

Usually, I'll add 3dB-6dB or so more above what I think I'll need, unless I'm maxed out (in which case, it becomes a too much gig for the rig and we're under-spec'd).

Doing it this way gives me an idea of what SPL I'm hitting when my meters are running around "0" and helps keep my mixing in-check as ear fatigue sets in.

Would calibrated SPL measurement help? Maybe...but I think it's the thought process behind it that is helpful.
Title: Re: Setting Levels on Powered Speakers
Post by: Patrick Tracy on May 04, 2021, 01:49:56 pm
Very interesting discussion.  I loved the M32R article.  Minus 18db digital equals +4 db analog.  That is a perplexing statistic.

It's not too perplexing. Analog would have an optimum level above the noise but with headroom to accommodate dynamics, so the zero has plus and minus around it. Digital has an absolute brick wall at the top of the scale, so zero starts there and all values are negative. The "normal" digital level is set to a value far enough below zero to accommodate dynamics.

Most likely -18dBFS (digital) = 0VU (analog meter) = +4dBu (voltage). Not everything is exactly that. Some AD/DA converters put 0dBVU at a different value, perhaps -20dBFS. Some analog mixers (Mackie) put 0VU at 0dBu.
Title: Re: Setting Levels on Powered Speakers
Post by: Alec Spence on May 04, 2021, 02:43:46 pm
Very interesting discussion.  I loved the M32R article.  Minus 18db digital equals +4 db analog.
....
I never really push my speakers past 4 o'clock and seldom have clipping issues.
I love the fact that, however technical we get with gain structure everywhere else, the speaker attenuator is so often by "clockface"  :)
Title: Re: Setting Levels on Powered Speakers
Post by: Debbie Dunkley on May 04, 2021, 03:54:30 pm
I love the fact that, however technical we get with gain structure everywhere else, the speaker attenuator is so often by "clockface"  :)

I suppose its because there are usually no numbers or anything to tell where the setting is on the attenuators so it makes most sense??
Title: Re: Setting Levels on Powered Speakers
Post by: Scott Bolt on May 04, 2021, 05:18:26 pm
I love the fact that, however technical we get with gain structure everywhere else, the speaker attenuator is so often by "clockface"  :)
I suppose we could use degrees from high noon ..... but that would just be too geeky ;).
Title: Re: Setting Levels on Powered Speakers
Post by: Ed Taylor on June 07, 2021, 11:52:31 am
pressing some old gear back into service as small town USA tries to reopen.

gear hasn't failed, so I still use it...so while it's not the hot brands and certainly not the best, it's still making me money. (so please be kind)

the rig I used last week  was mackie 1530 3-way tops over mackie SWA1801 subs.
total watts rated out of each box is 700...pretty whimpy compared to the ratings on single QSC K12 rigs these days I know...but the rig still sounds good and was paid for so very long ago. (2 per side)

the 1530s actually don't even have a "volume" knob on them. They do all they can do and you hit them with the gain structure off the board.
the mackie subs do have a gain control, and I tend to set that at about 2 oclock so they can keep up with the tops and give me headroom to adjust.
I do mix the subs from an aux sub path...my boards provide for full eq control on all aux, so it's not like the old days where an aux out to subs could not be adjusted in pre mode, meaning more outboard gear in the racks to deal with that.