QuestionQUESTION: hi, i just recently read a question from tyson you answered about the 12" pyle (plbw124) sub, i just bought two and was wondering how powerful of an amp i should buy, since you were probably guessing is could handle 175 rms, if i bought a bigger amp would if sound bad or blow?
ANSWER: Hi Ryan,
If you use more power than the subwoofer can handle, the risk is that it will be damaged. Nearly all the power that the amplifier sends to the subwoofer will be converted to heat. This is true of any subwoofer. The RMS power rating shows the maximum continuous power level that won't result in damage from too much heat. If you go past this level, the insulation on the wire may melt, the voice coil former may become deformed, or the adhesive holding parts of the sub together may give way. It's very likely that the subwoofer will start to produce audible distortion before this happens; however, because subwoofers are often located in the trunk, and there are usually interior speakers playing very loudly at the same time, you can't count on hearing the distortion before the sub becomes damaged.
That doesn't mean that if you buy a higher-powered amplifier, you'll automatically damage the subs. It really depends on the type of music you like to listen to, and how loudly you like to play it. For normal music listening, the average power level tends to be quite a bit less than the peak power level. That means if you buy a 500-watt amplifier, and play your music at maximum level, you probably won't be producing 500 watts on average. Depending on the music, you might push over 500 watts to the subs on musical peaks, but less than 100 watts the rest of the time. If your music has a lot of bass, including long, sustained bass notes, then the subs will be getting more power. The trouble is that there's no certain way to know when you're pushing too much power to the subs (especially when it's so hard to find the actual power rating, as it is for these subs).
Remember that the power produced by the amplifier will be divided evenly between the two subs. If you purchase a mono amplifier rated at 400 watts at 4 ohms, then at maximum RMS output each sub will be getting 200 watts. For normal musical listening, such an amp might work out well for those subs. Also, remember that when you have two 4-ohm dual voice coil subs, they can be wired for a final impedance of 1 ohm or 4 ohms. With those subs, I'd probably look for a mono amplifier with a 4-ohm RMS power rating of 300-400 watts. The nice thing about an amp like this is that it should be able to produce 500 watts or more with a 2-ohm load, so you'll be ready if you decide to upgrade your subwoofers later on.
Hope this helps!
Brian
---------- FOLLOW-UP ----------
QUESTION: Hello again Brian,
So I've bought a box for those pyle's, and bought an amp Kicker KX400.1, it says it'll push 400X1 RMS 2ohms, so I hooked the subs up parallel, but the problem I'm having is that when I turn the volume/gain/bass, anyone of them to try and get the subs more bass, it'll cut out, the amp will cut out, then after a couple seconds it'll turn back on, it'll keep doing until I either turn bass down or turn volume down. I'm pretty sure I hooked it all up right, I'll check again, thanks again Brian.
Ryan
AnswerHi Ryan,
If you connected the two subs in parallel/parallel (where each of the subs has its' voice coils wired in parallel, then both subs are wired in parallel to the amp) then the final impedance at the amplifier terminals is 1 ohm, not 2 ohms. This could certainly be why the amplifier is shutting down, as it's rated for a minimum 2-ohm load impedance.
It's not possible to combine two of those subs for a 2-ohm load. The best you can do is to wire them for a 4-ohm load with a series/parallel scheme: each of the subs has its' voice coils wired in series, then the two subs are wired the the amplifier in parallel. This is the only safe configuration for the amplifier, but you won't get the 400-watt rated power.
It's also possible that your amp is shutting down due to a voltage drop somewhere on the power line. This might come from a poor connection at the battery terminal, a problem with the fuse or fuse holder, or a poor ground connection. A voltmeter is very useful for troubleshooting this kind of problem. You can test the DC voltage at the amplifier's power terminals while it's playing; if it's dropping below 11 volts or so, then you might have a power wiring problem.
Hope this helps!
Brian
