I need to think about this for a few minutes, your idea about the pot. but I will say this:

DO NOT USE A DMM TO SET YOU AMPLIFER GAINS...Unless you only listen to test tones. And even then, you'd need more test gear to do it properly.

Use your ears, they are the best tool you have. The DMM method sucks ass and will not produce the results that you want. This method is severly flawed for many reasons and should never be used. I wish I knew why it is supported on so many internet forums. I challenge it whenever the opportunity arises.

 

And if so...would this affect my other amps? I would think that if I put all my amps in line (use RCA outs to go to ins on other amp) then it would affect it, but if I split my RCAs and only use the pot on the sub amp, this would work, right?

Correct

You could try one of these instead of trying to make your own:
http://cgi.ebay.com/PERIPHERAL-PRC1-RCA-REMOTE-BASS-GAIN-KNOB-BRAND-NEW_W0QQitemZ130112930251QQihZ003QQcategoryZ12040QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

I'd go with something premade too.

 

Now this is just my personal approach, but once my gain is set halfway correctly I just leave it alone (other than tweaking to get it "just right" a few weeks-months later )
I know higher end head units have a separate sub output that has adjustable level at the head unit itself, but I don't have that option myself.
My silly theory is that once the system is adjusted the only controls I SHOULD need up front would be Volume and basic tone control (some source material is eq'ed badly)
The other thing you might run into is that with the wide variety of levels of low end information on different CD's etc., that you will find yourself jacking the gain up and down ALOT trying to get everything to sound similar...and it isn't going to happen (plus you will drive yourself nuts in the process!)

Like I said this just MY approach... But I thought I would share it just for thought!

 

Welllll Guys there's a couple approaches here, as for premade.. Fooey! This is a DIY forum

Also remember, it's cut only, he's not adding gain. I have a 7.1 rig at work here that is set for standard, unfortunately it has no volume control "because that's how it is" (bastards) I put 8 VCA's ganged to one pot on there. Therefore when it's cracked wide open it's still "hunky dory THX or whatever standard" and can be brought down from there since everyone that uses it complains that it's too loud.

What is the value of the pot? I would like to see a linear taper int here too but it will work, it will just be touchy.

As you look at the pot with the shaft facing you (get your mind out of the gutter freaks) the first tag will get ground (signal ground) the middle tag will head off for the amps the last tag will get signal input. hopefully you won't get noise, remember that the center tag is the wiper, at it's lowest position it's sending ground as signal to the amp input... If your ground is "noisy"........

Chad

 

I put 8 VCA's ganged to one pot on there.

That's a better approach no? Pictures or a design please? I'd be interested in that, but I never seem to have time to design one myself. Actually, one using a rotary encoder would make me more happy becasue then I could just use the rotary encoder already on my HU.

 

I just used 8 of the RDL stick-on series. Nothing too fancy. I think the model number is ST-VCA.

The rig also does 2.1 via the extron switcher thru the autopatch. Unfortunately the Extron will not do big multi channel do the dipshit designer dumped the 7.1 OP into the auto patch and "set it and forget it" 2 days after the build and the first THX whiz-bang intro happend the battle was on. VCA's to the rescue.

I told them so... Nobody listened.. now I'm the designer... great



Chad

 

i use the david navone pontenti, best ive ever used, it can turn the amp completely off, not just down several db, but completely off, which is a very nice feature, it also is completely transparent and only $20.