Gain structure on a active system,

[The Dude]

I don't know if gain structure is proper, but here is what I have and want to know. If there is some readings I don't mind reading as long as they get to the point and make since to common folk like. But my pre has a volume knob, my minidsp has gain, and my amps have gain. How do I go about setting these to sound good. What I mean(not that I do this to my in home system), but in my Jeep I turned the receiver all the way up on the volume control, even did this with just a seperates system I had recently. Then turn the power amp up until it starts to distort and back if off. That way I have maxium out put my speakers can handle, with no distortion. The nice thing about this, is if one of the kids comes by and turns the volume knob up, it will get loud but not blow my speakers.

But know I have added the minidsp and a second amp in. My thought would be match the hf/lf within db levels using either the gain the minidsp or the power amps. Which in a since is how I have it, now I have it with the amps all the way, and adjust the gain as necessary with the minidsp to match the hf levels to the lf levels. I hope I didn't make this confusing like I seem to do. Help is all ways appreciated, as I think I am getting closer and closer.

Edited June 13, 2014 by duder1982

[derrickdj1]

The way I do things with my system is on the regular speakers, I turn the power amp all the way up and on the subs I have to adjust the amps starting around nine O'clock and then run autocalibration and let the avr/preamp adjust everything. This way everything can be controled by the avr/preamp remote. My sub amps contains a program like the Mini DSP. Once autocalibration is done, I check the trim levels and make further adjustments as needed.

I can make additional adjustment in the sub amps DSP without affecting the autocalibration settings since my subs are xo at 50 Hz in the avr/preamp and on the sub amp. MCACC dose not adjust the subs under 63 Hz. This way the avr can be turned all the way up to reference level and the speakers can't be damaged. I never go back and touch the subs amp or power amp to the other speakers.

Edited June 13, 2014 by derrickdj1

[NBPK402]

The way I do things with my system is on the regular speakers, I turn the power amp all the way up and on the subs I have to adjust the amps starting around nine O'clock and then run autocalibration and let the avr/preamp adjust everything. This way everything can be controled by the avr/preamp remote. My sub amps contains a program like the Mini DSP. Once autocalibration is done, I check the trim levels and make further adjustments as needed.

I can make additional adjustment in the sub amps DSP without affecting the autocalibration settings since my subs are xo at 50 Hz in the avr/preamp and on the sub amp. MCACC dose not adjust the subs under 63 Hz. This way the avr can be turned all the way up to reference level and the speakers can't be damaged. I never go back and touch the subs amp or power amp to the other speakers.

But isn't the max on the power amp volume where the most distortion is... Or does it only matter if you crank the preamp up that much too?

[derrickdj1]

The amp at 200 watts /ch is never using any where close to it max output so distortion is not a problem. The preamp voltage is adjusted in autocalibration so the amp turly is not turned all the way up. The avr can be turned past 0 db reference level but, under the MCACC control it can be limited not to go pass 0 db reference level.

Edited June 14, 2014 by derrickdj1

[The Dude]

I do want to be clear, I am not using a avr, but a tube preamp.

Sent from my HTCONE using Tapatalk

[Daan]

Your miniDSP has a input-level meter which goes from green to red, to indicate the incoming signal; that's your first adjusting-point.

If all is well then it should light up to orange during loud passages.

After that you could choose to set your power-amp at full if that does not produces extra hiss/ hum to avoid the influence of the pot in the signalpath.

Then; your preamp should end up somewhere around 10-12 o clock at normal listening levels after adjusting the output levels of the miniDSP.

My three amps do not have a volume pot [ I removed the ones on the back of the Decware's] so the signal has one less "resistor" to go thu.

I only described the way I adjusted the gains in my install as it works the best for me.

Nico

[The Dude]

your preamp should end up somewhere around 10-12 o clock at normal listening levels

With the way I have it set up know, if I turn it to 12 o clock, it is way to loud.

I adjusted the gains in my install as it works the best for me

That's good to know, as it sounds like it may be one of those things that works best for you. Though it would be interesting to know if there is a right or wrong way, and specific reasons why.

Good info Nico, thanks for posting.

[Daan]

Then you did not use the last field in the miniDSP menu yet ?

In that last stage you can set the attenuation for every seperate driver down to zero if you wish.

So with two options; control the attenuation at the input [from green to red ] and at the output, you are able to have full control over the overall attenuation of the miniDSP ; it will not amplify the signal, only attenuate it.

So just as with the car stereo, you can turn up your tube-preamp volumeknob up to the desired setting on which you want to reach full volume and then attenuate it by using the controls of the miniDSP as described above.

Steve Deckert wrote a article about gain, I'll try to find it and post it here for you; he can, in a professional way ,explain this matter.

Edited June 14, 2014 by nico boom

[Daan]

Here is something that might help; http://www.decware.com/paper55.htm

[Rudy81]

I used this article to help me understand what I was trying to accomplish when I was working with my gain structure issues.

http://www.prosoundweb.com/article/how_do_you_set_system_gain_structure/