Quick Gain setting question

[BlownEARdRUMS 10+ year member]

Ok thanks to popular demand I’ve ditched my old multi brand, tri sub, setup and browed my friend’s setup. It consists of 1 Hifonics BX1000d, 1 Audiobahn AW1200Q in a single bx and 2 others that I cant get any info on in a double box. I measured the single with my DMM and got a reading of 2.8 ohms and the double came out at 8 ohms exact

If I am correct I should take

SQRT(amps output)X(Ohms) = Volts à SQRT(1000)X(10.8) = 32.86 Volts

Is this correct?

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[squeak9798 5,000+ posts]

Ok thanks to popular demand I’ve ditched my old multi brand, tri sub, setup and browed my friend’s setup.

I tried telling you to do that like a year ago.......

It consists of 1 Hifonics BX1000d, 1 Audiobahn AW1200Q in a single bx and 2 others that I cant get any info on in a double box. I measured the single with my DMM and got a reading of 2.8 ohms and the double came out at 8 ohms exact
If I am correct I should take

SQRT(amps output)X(Ohms) = Volts à SQRT(1000)X(10.8) = 32.86 Volts

Is this correct?

Wait...I don't get it. Are those three different subs again? The Audiobling and then two others? Or are they all Audioblings?

Also...no, you wouldn't just add the ohms together. You would need to decide if you were going to wire them in series and parallel together and calculate the final load from there.

And you wouldn't use 1000w for the power because that amp is not going to put out anywhere near that power level at the high final impedance load you're going to arrive at. You would use whatever the output of the amp would be at the impedance you will obtain.

Anyways...more info here. What are the other two subs? What is the power handling of those subs? You may need to pull the other two subs out and rewire them to a different impedance.

 

[BlownEARdRUMS 10+ year member]

Yea three subs but inly s are diff this time

The single is suppose to be 4 ohm and 700 watts its a DVC currently wired in parallel

I pulled out one of the subs in the double box and its also a DVC wired in series and the box is suppose o be 800 watts and 4 ohms

 

[squeak9798 5,000+ posts]

Yea three subs but inly s are diff this time

Was that supposed to say "but only 2 are different this time".

If so, that's not any better.

Use all the same subs, or don't use any subs.

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[BlownEARdRUMS 10+ year member]

Alright im ditching the single sub and will keep the double that is 800 watts and 4 ohms

Now what

 

[squeak9798 5,000+ posts]

Now you need to find a new amp since that Hifonics only puts out an overrated 250w @ 4ohm. You'd probably see 150w - 200w RMS out of it at most.

Which would be severely underpowering those subs if they are truly 800w RMS for the pair.

 

[iceteebone 5,000+ posts]

is that single or dual 4 ohm? if it's dual wire in parallel for a final 1 ohm load. then take power (1000) and multiply that by impedence (1 ohm in your case) that equals 1000. you then take the square root of that number which equals 31.6. now you disconnect the speakers, turn the gain all the way down (note the larger number is all the way down) put your positive and begative lead of your dmm on the amps positive and negative speaker terminals. play a 50 hz. tone with your headunit setup the way you listen to it, and volume at 3/4 the way up. slowly increase your gain until you reach 31.6 then back off a little.

 

[BlownEARdRUMS 10+ year member]

I havent tested the 2 subs indepently but teh box is set up as a mono steup meaning there is only one +,- connection for the 2 subs. At the connecter I get at reading of 8 ohms exact. I am starting to think about swicthing over to the single so I could get a little bit more power from the brutis. Is this a good idea becuase I belive that the single is 700 rms and the doubles are 800 max. The internet says that the single sub is rated at 4 ohms but I get a reading of 2.8 on my DMM. Its parallel right now is there any way to get it lower.

 

[qtipextra 5,000+ posts]

The hifonics bx100od that I own will put out about 28 volts rms. You can, however, jack it up to about 46 volts (MAX), but I do not recomend that, because you would just be asking for problems, both in the amp itself (putting a hell of a strain on it) and on your subs (distortion and possibly square waves). Great amp, just a bit overrated. But it sure pushes my SE's good with 350-400 wrms to each sub (with a total resistance of 1 ohm), even though im underpowering them, but half of that is the effiecency of RE's products.