Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Masis Ingilizian]

I am keen to understand more about decent options for DSP for a large venue. The sound engineer for the venue states that the QSC TouchMix 30 Pro has DSP and the specifications on the website does mention "room wizard to simplify equalization tasks." Does this DSP have enough taps and how would it compare to a DSP such as the DBX or other similar type DSP's such as the Silica?

Apparenlty the QSC even has the option to put a mic and play pink noise to get a measurement. If I am not mistaken the PA2 also has this option which is automatic if I am not mistaken? Any input would be helpful.

[Caleb Dueck]

I am keen to understand more about decent options for DSP for a large venue. The sound engineer for the venue states that the QSC TouchMix 30 Pro has DSP and the specifications on the website does mention "room wizard to simplify equalization tasks." Does this DSP have enough taps and how would it compare to a DSP such as the DBX or other similar type DSP's such as the Silica?

Apparenlty the QSC even has the option to put a mic and play pink noise to get a measurement. If I am not mistaken the PA2 also has this option which is automatic if I am not mistaken? Any input would be helpful.

The processing ("DSP") in a mixer is for adjusting inputs, IE, EQ, compression, etc of the inputs.  While there may be some slight capabilty on the outputs, not only is it not enough, but any BE can mess it up. 

Input adjustments happen in the mixer, speaker system processing happens in a DSP. 

A PA2 isn't what I consider a "real" system DSP, unless it's a self-powered system that needs nothing more than a couple EQ filters and some light delay. 

Pink noise and auto-EQ, from any manufacturer or device - is a waste of time, and can end up worse than nothing. 

[Don T. Williams]

Both the QSC and the DBX offer this feature.  In my experience, neither works very well.  The problem is the mic is in one single position, so it might sound right for a person standing in that one spot.  That's a big "might".  These systems are based on what the RTA (realtime analyzer) "hears" in that one position.  Move a few feet and there can be huge changes.  If you can make dozens of measurements and average them, it will be better, but the RTA can't perceive sound the way a human can.  To me, the automatic functions may kind of work in the mid frequency range, but are terrible for high and low frequencies, and the results never sound right.  They seem to "over equalize" from my experience.

I have had better luck using the narrowband automatic anti-feedback filters.  These are narrow enough to find room resonant frequencies that tend to affect the entire room.  I will usually let the system set 4 to 8 of the worst offending frequencies.  These are very narrow filters that take very little out of the overall sound, and getting rid of the worst of these frequencies is a great first step.  From there I will use broader band EQ to balance the system and then make certain that equalization didn't cause more the feedback problems.

Try both methods and see what works for you, but nothing works as well as learning what equalization is and how to use the equalization tools available.

[Steve-White]

I am keen to understand more about decent options for DSP for a large venue. The sound engineer for the venue states that the QSC TouchMix 30 Pro has DSP and the specifications on the website does mention "room wizard to simplify equalization tasks." Does this DSP have enough taps and how would it compare to a DSP such as the DBX or other similar type DSP's such as the Silica?

Apparenlty the QSC even has the option to put a mic and play pink noise to get a measurement. If I am not mistaken the PA2 also has this option which is automatic if I am not mistaken? Any input would be helpful.

Pretty much any outboard processor is an improvement over built-in stuff.  The dbx Driverack PA2 is a great starting point to learn system controller setup and operation.  It'll get the basics done and doesn't take a degree in quantum physics or network engineering certification to operate.

[Masis Ingilizian]

Apologise for not replying individually. Firslty thanks for the responses. Secondly, if some of you remember I was doing the acoustics for a wedding venue and had previously asked about sound systems. The acoustics part of the job is nearly done, I have achieved an approximate 1.5sec RT60 flat to 1k then a slopping curve to 10k. I should get to 1.1sec once new cushion chairs and people are in, we can add some more panels if need be but the idea is to stop and give the owner a taste of what it sounds like. So, my next goal is to rent locally a sound system and assure the owner that with a correct sound system(not the VRX he often rents) overall with its accompanying reverbertaion time the venue should sound good and no need to spend more on the acoustics and probably better spent on a sound system. The venue has a person who will organise sound system for rent or for future purchase however there are limitations on what he can organize. So, my goal is to try and guide or direct the options according to best practises rather than what suits him or makes him more money. He is very accomodating and works well with me, just that he doesn't have many options.

A dedicated outboard DSP is something that is needed regardless at least from my understanding from the above responses, so I will recommend that to the owner and am discussing options with the sound engineer, like I said he seems to know his stuff to a certain degree but the issue remainns that if he can't organise that piece of equipment there isn't much he can do at least for renting. For future purchases all I can do is a recommendation to the owner. It will be his decision if he wants to be limited by the sound engineers audio equipment option. This outboard DSP purchase can be used for the time we rent and then later used again when he purchases a decent sound system sO nothing to lose to go ahead with this.

Apparently the sound engineer has a sound check guy who knows how to use dedicated outboard DSP, this is good news.

Okay, so the PA2 is basic can do the job but nothing special can you guys recommend me something that is a step above? I suppose your going to ask what teh system entails but to give an idea there are bands playing and DJ's.

I also understand about automatic DSP/Pink noise, I thought they would be effective and that technology perhaps has brought it to a stage where an automatic calculation would be good enough but obviously not. My question here is if there is any point in purchasing a dedicated outboard DSP with the option of automatic filters/correction? Does it help enough then one can use there expertise to change the filters or no point in the first place? Is best practise to just use the sound engineers expertise over the automatic adjustments?

Narrowband anti feedback filters, if you can just point me in the direction of what this is and if its on a outboard DSP or anothr piece of equipment, I can look into it a little more??

Learning equalization and how to use those tools available is the most importnat I also fully understand that, in this case I lay my hope with the sound check guy but at least for the one off ocassion that we will rent, I will accompany the sound check guy if need be use REW to measure and use my knowledge of room modes and equalization from small room acoustics (which I know is very different) to see if he is on the right track. Best case scenario is that he is more qualified than me and he can handle it. You can see that I am  invested in this one off renting option because an incorrect sound system can soud bad even if the acoustics are great. And if he decides to purchase a decent sound system in future I will recommend him to use a sound system desginer, which I have in the past but for now the goal is to have a decent sound system as a one off to rent.

Just to confirm, my job isn't so much to organise the entire sound system, monitors and all that stuff, I don't need to get into. All I want is to rent two main speakers capable of clean powerful output with a some type of pattern control with a dedicated outboard DSP and proper subs. I have done research on subs for large venues, I know that is a problem and in this case we are limited but I will try and simulate on Ease Focus to show them the problem, if they put it on the sides then its their problem The rest, monitors, etc is really not my job. So hence the point of this thread, so I can get a decent outboard DSP or at least know enough about it to recommend one over a mixer, then choose two proper main speakers with the options available. It seems the best is the QSC K12.2 with dual KS118 subs, the other brands are random Spanish unkown brands and are line arays, from our last thread point source was decided as best for this venue.. The QSC is the only point source he has available, I would have prefered passive and with 15inch but no options available.

[Brian Jojade]

Many digital boards these days have enough processing on the outputs that an external processor is no longer a requirement.  This is great for YOUR system that YOU operate.

If you're having other people operate the rig, using the external processor means keeping all of the settings out of the hands of others.  ie, they can't go in and muck it up, accidentally or otherwise.

It would be neat if there was a way to password protect the processor settings, but that doesn't seem to be a feature available on any of the entry level boards which fit in a market where saving money on a processor matters more than the high end where external processors are a given.  Weird.

[Dave Garoutte]

One big advantage of a passive system, is the room (permanent) DSP can be in the amps and not available for adjustment by the engineer du jour.
BTW, where are you located?  For high quality pattern control Danley Sound Labs is hard to beat.  There may be a dealer or provider nearby.

[Masis Ingilizian]

One big advantage of a passive system, is the room (permanent) DSP can be in the amps and not available for adjustment by the engineer du jour.
BTW, where are you located?  For high quality pattern control Danley Sound Labs is hard to beat.  There may be a dealer or provider nearby.

So taking your repsonse in perspective your line of thinking is that the mixer should be good enough except it means running the risk that after a long days hard work of geting the sound right it might be lost when another band comes and sets up, did I understand this correctly?

My second question would then be, is the QSC touchpro decent enough compared to an outboard DSP say an entry level on such as the DBXPA2?

[Masis Ingilizian]

One big advantage of a passive system, is the room (permanent) DSP can be in the amps and not available for adjustment by the engineer du jour.
BTW, where are you located?  For high quality pattern control Danley Sound Labs is hard to beat.  There may be a dealer or provider nearby.

Yes, thats right, it is one advantage and of course I don't have enough experience to say active amps in speakers might or might not be powerful enough, I just get the feeling that your going to get more headroom with a external amp.

I am in Yerevan, Armenia and for purchase the sound engineer might be able buy outside the currrent range he has, but for rent anything of that quality is not available. Danley would be one of the better options but also very expensive so I would need a few steps down from that, perhaps in that QSC quality range. The best option for renting is the QSC options I mentioned above, the K12.2 and the KS118 Sub. The other option is an unkown brand Next Pro Audio

https://www.next-proaudio.com/products/LA122A# but its a line array, I want to simplify things with point source however I guess the line array will have more power. After deliberating and with photos in other forums, point source seems like the preferred option in this venue.

[Scott Holtzman]

Yes, thats right, it is one advantage and of course I don't have enough experience to say active amps in speakers might or might not be powerful enough, I just get the feeling that your going to get more headroom with a external amp.

I am in Yerevan, Armenia and for purchase the sound engineer might be able buy outside the currrent range he has, but for rent anything of that quality is not available. Danley would be one of the better options but also very expensive so I would need a few steps down from that, perhaps in that QSC quality range. The best option for renting is the QSC options I mentioned above, the K12.2 and the KS118 Sub. The other option is an unkown brand Next Pro Audio

https://www.next-proaudio.com/products/LA122A# but its a line array, I want to simplify things with point source however I guess the line array will have more power. After deliberating and with photos in other forums, point source seems like the preferred option in this venue.

That link you provided can't even provide a secure connection (no recent cipher) that it can be browed with a modern browser so that speaks volumes to the lack of attention to detail the company has.   I can't imagine they are capable of designing an audio system. 


You seem very married to QSC.  It's decent stuff but can't you get Yamaha or JBL?  The Yamaha tops are worlds ahead of the QSC for the same price.  I run Yamaha DSR112 over QSC subs.  I moved all my K and KW inventory to monitor duty.


As far as the Touchmix it is ok, it runs sluggish.  So many better mixers on market.  Can you get Allen and Heath or Midas?


The PA2 processor completely sucks.  They don't begin to unsuck until you get to the Venue 360 model.  The Zilica you mentioned is light years ahead.


You spoke of taps.  Taps only matter if it supports FIR filters.  If this feature is important you need to check closely.  Also speakers like the QSC have built in DSP not sure what you need a processor for.

[ProSoundWeb Community]