Whats up guys? Looks like I'm picking up a pair of Power Acoustik 10's this week. The subs are rated for 1800 watts. I think they're 600 watts RMS. So...in order for these to sound good, whats the minimum amount of power the amp I get should have?

 

First, forget the bullsh!t number on the sub. The amount of power needed depends on how much is required to reach full excursion or before power compression. If you are buying an amp in the 'Power Acoustic" world then buy 4000 watts since that should give a good 400 to the subs. In reality (which seems to be very rare in car audio these days) 300 watts per sub is plenty for good output and long life.

 

Sounds good, thanks. Quick question to go with that though. How do I find out how much power is needed to reach full excursion? I'm a total newb when it comes to car audio so bare with me....

 

Power ratings for subs are based on the power level required to melt the voice coil. The test is open air in a temperature controlled room. It is done with a steady test tone. In the real world with a sub in a box in a trunk the temp is much higher to begin with so this doesn't mean much. THe equipment that can accurately test performance is expensive and the results are poor so they do it the BS way and then multiply by 3 for the Max power number. (They used to multiply by 2 until a marketing genius decided to make their brand better than everyone elses).

Typically when you see the rated RMS power figure, around 70-80% of that figure will give full excursion. The extra power will not move the speaker any farther in a linear fashion. You can force it further and gain a little more output and a lot of distortion but this will really creat much more heat and damage a speaker as well as stress the suspension. After the point where you reach power compression you need much more power to gain any output. For example, if you have 300 watts providing 80% exxcursion it could take 600 watts to reach 90%. The damage caused isn't worth the gain.

So many people buy crap and wind up replacing it every year when good equipment used properly will last forever. I would put around 400 watts per speaker, in a correct enclosure and you'll be fine.

Don't get me started on the bullsh!t amp ratings that are given...

 

haha in other words...

a nice 600+ mono amp at 1 ohm should make you happy, just run 12 guage wire all the way to the sub and you wont have much loss

 

That is another xar audio myth. An amp puts out high AC voltage and the awg of wire will make a minimal difference.

All speaker (transducer)systems are inefficient. They take electrical enrgy and convert it to mechanical energy. This process is only around 3-5% efficiency. Amplifiers are around 50$ efficient so you can see there is a lot of wasted energy in audio. The losses from wiring is miniscule but I always use at least 14ga as that is plenty for most systems with no sacrifice in performance..

 

So...600 watts power rating or RMS for the amp?

 

Look for an amp with a 60 - 90 amp fuse to have enough power. There are amps that say 1200W RMS with 30 amp fuses that will put out 300W at best.

 

Got it. Thanks.

 

haha yes 600+ at max power :P personally i wouldnt buy off brands either, and look for a good signal to noise ratio like 98 is a good number .. and dont pay attention to the store/site bull about power, its better to ask people about products and see how they like them first if your not sure

just tryin to keep it easy for ya

 

sorry to burst your bubble but there is NO power acoustik 10" that handles 1800 watts. the closest sub would be their FX line which "claims" 1600watts but is really only 800 watts RMS!!!!! FOCUS on RMS power, not peak power.

as far as amps go, u need to be looking for a class D amp with the lowest THD (total harmonic distortion). look for THD readings of 0.05 or LOWER. that way the clipping won't blow the subs in 3 months...

 

There is no class D amp with a good THD. Class D amps square wave all output by design. Distortion isn't really as audible at low frequency and it isn't a problem.

Class D amps give there specs at static 4 ohm loads at 1,000 Hz.

When have you seen a Class D amp used at 4 ohms?

When have you seen a Class D amp playing 1KHz? Not including Tripath Class D technology of course.

THD is the most overrated spec in audio. I 100% guarranty that your ear has a THD threshold of at least .2 or 20%.

S/N is important as long as it is above 96db. That is the S/N ratio of a CD, you just don't want to make it worse. Most of the pretty lights, DSP, mega head units have S/N of around 92db and remember you can't make it better so its only as good as the worst component in the system.

 

Actually there is no bubble to burst buddy. I was just going off of what was printed on the inside of the box that the subs came in. They're packaged in a chest like box. Once you open it, printed on the inside of the lid are the rating and specs I've mentioned earlier. The subs claim 600 watts RMS and 1800 peak. They're the FUBAR (sp) series 10's.

 

Thanks bro. Appreciate the advice. I wouldn't buy off brands either, but a guy I work with is giving me a good deal for the subs and a box. I'm craving bass, so I'm just gonna use these as a stop gap until I buy some serious hardware.

 

First of all what is the sub model? ****, FUBAR, FUBR, KWS, BL, BM, or FX?????