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Title: Somebody check my calculations on these DSP setting?
Post by: Marsellus Fariss on April 18, 2011, 09:56:27 pm
biamping LA460's with Crown K2's on the Low/Mids and QSC MX700 on the HF drivers. Each bridged into two cabs a side.

EAW's tunings say L/F +7 and HF -3.

K2's gain is 32.88dB using the 1.4v sensitivity setting. +6dB for bridged operation = 38.88

The QSC's gain is 31dB +6 for bridged mode = 37dB.

So the DSP's gain settings should be adjusted 1.88dB for the difference making:

Low/Mids +7 and HF's -1.12

Am I doin' it right?
Title: Re: Somebody check my calculations on these DSP setting?
Post by: Marsellus Fariss on April 20, 2011, 04:21:12 pm
What I really need to know is do you adjust the gain in dB of the DSP proportionally to the gain of the amp in dB? So if one amp produces 5dB more gain then the other your using on the same cab you should adjust the output gain at the DSP 5dB lower for that band to compensate?
Title: Re: Somebody check my calculations on these DSP setting?
Post by: Bennett Prescott on April 20, 2011, 05:27:53 pm
Why not just use fixed gain on your amp (i.e. 26dB (x20) or 32dB (x40))? Then you don't have to do all this math, your relative levels actually are, and if you swap out another amp in the future you don't have to change your crossover settings.
Title: Re: Somebody check my calculations on these DSP setting?
Post by: Marsellus Fariss on April 21, 2011, 07:59:45 pm
Why not just use fixed gain on your amp (i.e. 26dB (x20) or 32dB (x40))? Then you don't have to do all this math, your relative levels actually are, and if you swap out another amp in the future you don't have to change your crossover settings.

I dont wanna put 1250 watt on 2 150 watt drivers when I can use another lower watt amp and put that power somewhere where it's really needed.
Title: Re: Somebody check my calculations on these DSP setting?
Post by: Mac Kerr on April 21, 2011, 08:23:13 pm
I dont wanna put 1250 watt on 2 150 watt drivers when I can use another lower watt amp and put that power somewhere where it's really needed.

What does that have to do with what Bennett suggested? The output power doesn't matter, the gain does.

Mac
Title: Re: Somebody check my calculations on these DSP setting?
Post by: Marsellus Fariss on April 22, 2011, 02:48:17 am
What does that have to do with what Bennett suggested? The output power doesn't matter, the gain does.

Mac

The QSC I'm using on the highs does not have a fixed gain option unfortunately. The only amp I mentioned that does is the Crown K2. Which is 1250 per side at 4 ohms. And I want to use that headroom elsewhere. I should have been more clear in my last post about that. Bennett had a good suggestion if applicable but out of 200+ views on this thread nobody has actually answered the question from my original post which was does amp gain (in dB) differences directly translate to how you adjust the output (in dB) at your DSP for different outputs. I did however find the information from another forum. The answer is yes.

I gotta be honest with you guys that lately I find more criticism then help on these forums and I think three times about posting anything or answering someone else post. And I've been here since the CompuServe days when I was just a kid mixing in bars and talent shows. And I don't mean to diminish the depth of valuable knowledge and experience members have here but you guys should really try and help more than criticize. Any number of members could have helped me out pretty quick. I've been met with downright hostility, assumptions and name calling by people I've never met in the last couple years on these forums and I really really hate to see that around a place I've loved and learned so much from over the years.