help with 12.9 volt to 14 volt please

[el_chupo_ 10+ year member]

I have a US acoustics usx600d. The manual that came with the amp says its rated at 300 watts RMS @ 2 ohm at 12.9 volts. with a dynamic power of 600 watts. I know the dynamic power rating means nothing, but how do i convert from 12.9 volts to 14.4 volts so i can correctly set my gains so as not to clip? Thanks

sub will be a single alpine type r dual 4 ohm

Matt

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[Moe Lester 10+ year member]

when your car is on, you should be seeing 14-14.4 volts. when the car is off, it should sit around 12.9

 

[el_chupo_ 10+ year member]

Thanks moe, I understand that, i wasnt clear in my first post. My question is how do i figgure out rms wattage at 14.4 volts.

I found a post that said (x/12.9)*14.4, but this gives me an output of 334. My old amp, a blaupunkt, was rated at 200w at 13.8 volts and the birth sheet said it was putting out 250 W rms @ 14.4v. My friend has the same amp and his is doing 247W rms. this is an increase of ~25%, and i was figgureing that going from 12.9 would give me at least an equal ammount of power, say maybe 350 W RMS, but if there isnt a formula, then ... THanks all

Matt

 

[Moe Lester 10+ year member]

well not all amps are the same efficiency and are going to create power differently, so if you can make an equation that works somewhat accurately with one amp, it probably wont work with another. If that amp has a fully regulated power supply (i highly doubt it does) then it would do the same wattage from 11-16v or so.

 

[el_chupo_ 10+ year member]

anyone know of a formula i can use??

Thanks

Matt

 

[billy18bm 10+ year member]

just cross multiply

around 360watts @ 2 ohms

i just took 300 over 12.9 and then x over 14.4

then crossed

so

12.9x=4320

x=360 watts

 

[el_chupo_ 10+ year member]

billy, thanks. I ended up with those numbers too, i just wasnt sure if it was right

Jmac, i was thinking of doing that, except rated power is 300 watts. My thoughts went something like this,

If i set the gain at 12.9 volts and set the gians at thier limit, when the car is running and producing 14 volts, it will be producing more power. This has the ability to overpower my subs.

If this isnt correct, let me know. Thanks

Matt

 

[req 5,000+ posts]

well. to be honest, none of this matters, because your USacoustics has a regulated power supply and it will only take in 12.9 volts maximum.

so you only got 12.9 volts to work with //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

so it cant do anymore power with the car on. *gratzi*

 

[el_chupo_ 10+ year member]

req, thanks alot. are all us acoustics regulated, or am i lucky?

Jmac, i know that is what the website says, but the manual that came with my amp rates it at 300W RMS. I called us acoustics at the phone number on thier website, and talked to 2 different people, both telling me that the number in the manual is what i should use. I dont know that they know what they are talking about, as i had to explain 3 times why i was calling, but that is what they told me. If you got any proof or reason to believe the 375, i would like to know, i bought the amp thinking i was getting 375w...Thanks all for the help

Matt