Snake Charmer

Dear SoundMan - I 'm curious about the output levels on the DSP 244 in the Cobra System. Should they be set at the detent { -6 db} or should they be all the way up? Will the system run safely if they are all the way up? - Thanks, Snake Charmer

Dear Snake Charmer,

That's a great question that brings up a very important topic when running a sound system. Here is the response that Hans Bürger, who is the product manager for Dynacord in Germany, gave to that question a while back:

"It's a question of setting the gain structure and how that effects the limiters inside the DSP. In comparison with other manufacturers - without passive safety-circuits inside the speaker - the limiter setting is not so critical for Cobra due to the internal voice coil tracking protection. However it is critical considering the headroom and limiting of the DSP. One example... Consider a 4 way system. If you have all the DSP outputs set at full and would like more of one particular band pass, you would then have to turn down the other 3 bands."

"You can safely run with the output levels set full. However, you then are in danger of limiting for the amp and the speaker. Generally, it would be wise to leave the outputs at -6, depending on the application, operator etc... If you are confident in the operator, you can run full open. However, if the operator is not capable of understanding the system, they could run into limit and not realize it. This can make for bad sound and possible failure!

"In all my demo-systems I open the output levels of my DSP´s without limiter changing. I never have problems. In our amplifier is a internal "analog" limiter and this only allows an output signal with max 1% distortion. The max input in the amplifier before clipping of the pre-amps is 21 dBu !!!"

That's great advice for sound systems in general. If you ever go to the audio for operators seminar given by Pat Brown of Synaudcom (and you should if you aspire to be all that you can be), that's the first topic he discusses. You hardly ever hear the local sound guru discussing such things when he's rappin' db's to impress the locals where head room is the empty space underneath his hat and gain structure is his game plan for getting rich in sound biz. That insight should help to explain why there is still so much bad audio even though we have so many cool new tools.

-SoundMan-