Help setting gain.

[j4tk]

I have two OA 18s that I'm trying to run.

I don't know how to go about doing that with an amp that's rated 2x the amount rms. The amp is a 2500@1 ohm and subs are 600 rms. And the gain right now is maybe halfway. They're not as loud as I'd like them to be.

Any help is appreciated. Thanks.

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[wew lad 5,000+ posts]

what amp are you using? maybe its rated 2500 @ 1, but that doesn't mean it will put out anywhere near that much

 

[fly_marlin]

I have two OA 18s that I'm trying to run.
I don't know how to go about doing that with an amp that's rated 2x the amount rms. The amp is a 2500@1 ohm and subs are 600 rms. And the gain right now is maybe halfway. They're not as loud as I'd like them to be.

Any help is appreciated. Thanks.

What's your deck's output voltage? If you're not sure, what model is the deck?

 

[C1500martin 10+ year member]

1. go to sears or home depot, buy a $20 dmm

2. READ vvvv

How to Adjust Amplifier Gains Using a Digital Multi-Meter | Learning Center | Sonic Electronix

 

[j4tk]

1)Hifonics.hfi 2500.1

2) pioneer deh p8400bh 4v.preouts

3) I have dmm and did that, for 1200 rms instead of the full 2500

 

[poolman966554]

1. go to sears or home depot, buy a $20 dmm2. READ vvvv

How to Adjust Amplifier Gains Using a Digital Multi-Meter | Learning Center | Sonic Electronix

thats seems like only half the story. you almost need a oscope to establish un clipped signal.

by sonics method, and using this amp : Amazon.com: Boss Audio R1100M - 1100 Watt, Monoblock, Class A/B, MOSFET Amplifier With Remote Subwoofer Level Control: Car Electronics

i doubt their method will work properly in this analogy . We/I know this because i stand on the shoulder of giants.

Edit: OP you can double check you settings by using a DMM and a clamp style DMM. if you play a 50 hz sine wave and clamp the positive speaker wire to see amp draw, and use your DMM to test voltage at pos and neg speaker terminals , then you can multiply the two readings to get watts thats going to the subs.

 

[C1500martin 10+ year member]

1)Hifonics.hfi 2500.12) pioneer deh p8400bh 4v.preouts

3) I have dmm and did that, for 1200 rms instead of the full 2500

Yea for amps like that i dont trust them doing rated at all clean, an oscope would be best in your situation. I think youd be safe calline it at 1800w amp and setting your gains at 1800. Overpowering a sub doesnt matter to a point because they almost never see the power due to box rise and voltage drop.

 

[gimling]

whats the voltage reading on the battery when running 50hz tone with subs hooked up? Whats the AC voltage on output of amp with subs hooked up?? whats impedance of the subs ??

 

[poolman966554]

whats impedance of the subs ??

very good question. i had just Assumed he was wired at 1 Ohm.. that said, What ohmage are you wired too??

OP thats very important bit of info we need to know to help

Although, if OP math was right, then rms should be right? depending on amp capability

 

[j4tk]

1ohm

 

[gimling]

1ohm

ok what you can do with the speakers hooked up to the amp, play 50hz tone at whatever you have your max volume set to, be it 3/4 of the way up on the deck or whatever, its a pioneer with 4V preout your not getting 4 volt till you would be max volume but at that point its going to clip. so lets go with 3/4 of the way up, take your meter check the ac voltage on the speaker output of the amp,(with subs playing). now take the voltage and square it, and divide it by 1 ohm and that will tell you what your currently run max RMS at. so P=V^2/R. i ask what your voltage on battery is with this frequency running to see if your electrical is holding up, if its not and your at say 12v it is possible that your driving amp into clipping.

 

[j4tk]

to see if your electrical is holding up, if its not and your at say 12v it is possible that your driving amp into clipping.

Electrical is pretty bad, stays a quarter above 12 while driving, goes below when I idle to long. And unfortunately an ho alt specific for my car, already made right to fit in stock, would cost 700+

Edit: only have one battery, duralast agm platinum

 

[gimling]

could do the big 3 and add a second battery and you should see a pretty big difference.