Setting Amplifier Gain Control

[ChevyBoy]

Im going to master/slave my amps but the dude at my shop said id have to match my gains, another guy at the same shop said tune the master, slave will follow it. i got so confused bc i had 2 different stories from the same shop.

tune the master and be done with it

[slugdub]

I give up. I'll just use the little clip light on my amp. If that turns on, its bad.

Its fun to have a multimeter though, even if I have no use for it. Harbor Freight ftw (it was like $3)

[Blazerbass]

nicee. this helped me out

[1mtx1]

on my deck what should the bass level be set at? i have a 12inch si mag tune to 32 hz off a audioque 1200d. im playing a 50hz test tone should it b set to 50hz?

[Cavihitts]

I have a couple of questions on my amp. It is a Planet Audio BB1250.1. It is running 2 Treo SSi 12" dual 4's and is wired to 1 ohm.

First, I was adjusting the gain today by ear and it has the gain setting but also has a input sensitivity switch and you can select either 100mV-2V or 2V-8V. When I switch it to the 2V-8V setting and adjust the gain, there is no difference in output. The subs are playing but very low. Now if I switch it back to 100mV-2V, the gain setting actually changes output. Anyone have any ideas on why there is no difference throughout the 2V-8V setting. The deck is a Alpine 9813. Eq for lower frequencies are either flat or - (which that setting is not being changed during the process) and subwoofer level control at 12 also did not change. If I understand correctly, the subwoofer level control acts as an control for the level output. I have read that the deck puts out 4V with subwoofer level control at 15 but will be less at a lesser setting.

Second, the amp came with a birth sheet that has it at 1251@1 ohm. I don't want to dig the birth sheet up but I believe that the rating was with 12.x or 13.x v of power. The voltage readout that I have at the amp never really goes below 14.0V. Would the rated power be increased, even by a little, with the higher voltage rating or is it the same from 12-14.4V like some amps?

Thanks in advance.

[bumpnthump]

The bad thing about that link is that they only give the settings for the JL amps.  Just so everyone knows, the formula is AC volts squared, divided by impedance (ohms), equals watts.  So if I want 2000w @ 1ohm from my amp I'll need the sqare root of 2000 x 1 which = 44.72.  I'll set the output of my amp to 44.72 AC volts.  Or say I wanted 1500w @ 2ohms.  It'll be the square root of 1500 x 2 which = 54.77.  I'll set the output of the amp to 54.77 AC volts.

I'm curious, do you still cut the impedance in half if your bridging? So lets say I have a 1000.2 amp bridged to 2 subs at 4 ohms final impedance, would I cut it in half and do square root of 1000 x 2? Thanks!

[imfrom210texas]

I'm curious, do you still cut the impedance in half if your bridging? So lets say I have a 1000.2 amp bridged to 2 subs at 4 ohms final impedance, would I cut it in half and do square root of 1000 x 2? Thanks!

off-topic...your avatar is hilarious...on topic, this helps a LITTLE

http://www.the12volt.com/installbay/forum_...~TID~85479~PN~1

this is by ear of course, so take it for what it is, and use caution

[magillaru]

off-topic...your avatar is hilarious...on topic, this helps a LITTLE

http://www.the12volt.com/installbay/forum_...~TID~85479~PN~1

this is by ear of course, so take it for what it is, and use caution

I like how the 1st instruction tells you to wear ear protection...how the hell are you supposed to hear distortion when you have ear plugs or some other form of ear protection on...maybe they were referring to ear muffs in case you happened to be setting your gains in the middle of the winter! LOL!

On another note, could somebody please post the DMM chart for setting your gains. I'll keep looking for it on here, but if someone has the link, please help me out. Thanks!

Nevermind...found it!

[jvoisel]

I see nobody has been in here for a while but I'll give it a shot before I start a new thread.

Alright so does this all seem correct? I've got a saz-3000d that'd I'll be wiring down to 1ohm, on 2 AQ 18s ported to 35hz. 

Set gain, subsonic,LPF, bass boost, and phase all the way down on the amp. Bass remote disconnected. Set the sub out to max (+6 I think for me) on the headunit. DMM on AC plugged into speaker terminals with the subwoofers disconnected. 

Sq root of 3000w is 54.77 

Play cd with 50hz test tone and turn headunit volume up to 3/4. Turn gain up until I reach 54.77 volts on the DMM. Now disconnect DMM and connect subwoofers. Set everything else as:

Subsonic: 10(all the way down)

LPF: 70hz or so

Bass boost: 0

Phase: 0

Did I miss anything? Also should I try to get the gain set as close to 54.77 as possible or keep it down a little bit to avoid clipping? 

[kwag415]

I see nobody has been in here for a while but I'll give it a shot before I start a new thread.

Alright so does this all seem correct? I've got a saz-3000d that'd I'll be wiring down to 1ohm, on 2 AQ 18s ported to 35hz. 

Set gain, subsonic,LPF, bass boost, and phase all the way down on the amp. Bass remote disconnected. Set the sub out to max (+6 I think for me) on the headunit. DMM on AC plugged into speaker terminals with the subwoofers disconnected. 

Sq root of 3000w is 54.77 

Play cd with 50hz test tone and turn headunit volume up to 3/4. Turn gain up until I reach 54.77 volts on the DMM. Now disconnect DMM and connect subwoofers. Set everything else as:

Subsonic: 10(all the way down)

LPF: 70hz or so

Bass boost: 0

Phase: 0

Did I miss anything? Also should I try to get the gain set as close to 54.77 as possible or keep it down a little bit to avoid clipping? 

Great question i was wondering the same thing