Gain help when using 2 channels

[mike75356 10+ year member]

Alright so i have a cadance z9000 amp that im going to be using on my comps. Its rated at 300 x 2 at 4 ohms and 400 x 2 at 2 ohms. The thing is im going to be running them at 3 ohms on a set of boston acoustics pro 50's so i guess it would be around 350 watts. So what would i do to set the gains. I watched the jl gain setting thing and i got all confused cause it said you cut your ohms in half when bridgeing an amp.

So is this right?

(1.5*350) = ???

Really confused but i think im on the right page?

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[mike75356 10+ year member]

(1.5*350) = 22.91 or would it be (3*350) = 32.40???

 

[mike75356 10+ year member]

bump?

 

[mike75356 10+ year member]

Anybody?

 

[mike75356 10+ year member]

lol o come onnnnnnnnn bump!!!!!!!!!!!!!!!!!!!!!!!

 

[FoxPro5 5,000+ posts]

350x3 = 1050 then take the sq root = 32.4 volts AC. Keep in mind that this is an estimate and that you need to use your ears also. Listen to for the sound to break up or distort and then back the gains down or lower the HU volume.

I personally use this method after I set them by ear....sort of like a double check.

BTW, what is the preout voltage on your HU??

 

[mike75356 10+ year member]

Hey its a 4.0 volt pre out, pioneer premier 680

 

[FoxPro5 5,000+ posts]

Hey its a 4.0 volt pre out, pioneer premier 680

You know you need a few test tones, right??

So at like 75-80% max volume your HU is probably pumping out ~1 volt with a sine wave. Therefore, you are setting the gain at max unclipped votage based on that. With the power you are pushing to those speakers I would suggest leaving the gains all the way down and see how loud you can get the HU before it sounds distorded. I don't know when the HU will start clipping the signal...maybe some else knows where Pioneers do typicaly???

BTW, here's a great chart for future reference: http://www.installer.com/tech/techpics/ohmslaw.jpg

 

[mike75356 10+ year member]

Alright cool man thanks for the help i need it lol

 

[mike75356 10+ year member]

Yes i know i need test tones what test tone(s) should i used when setting these comps with this amp?

 

[azngotskills 10+ year member]

i used a 1kHz test tone for the comps and a 50Hz for the sub