What is the true power of subwoofer/speaker with specificatins: Norm .40 W , 240W Maximum?

Question

How many of these can a 254 watt amp, 150 watts RMS- 2X75 WRMS run

Answer 1

2 channel amp........2 speakers
4 channel amp........4 speakers

Answer 2

There are a few different things to consider when matching subs with an amplifier.

Just because the amp is a 4 channel does not mean you are limited to using it with exactly 4 speakers. same with 2 channel and one channel (aka. mono block). The easiest way to figure this out is to check the manual that comes with the amp. it will almost always tell you the best setup for that amplifier.

In the case you dont have that manual, the most important thing is the Ohm rating on the amplifier and the subwoofers. The speakers should say something like 4ohms or 8ohms on them (its ushually with the ohmega symbol).

And if you look at your amplifier booklet/box it will say what the minimum impedance (ohms/resistance) is. If it says 4 ohms then you can hook one 4 ohm speaker to it. if it says 2 ohms then you can hook up 2 seperate 4 ohm speakers to it. If your ohms (resistance) goes below the specification on the amplifier you will draw too much current and overheat the amplifier. To figure out how many ohms you have divide the value on each speaker by the number of speakers. So 4, 4 ohm speakers would give one ohm, which would toast almost any amp out there.

After you get that right then you can consider wattage. If the ohms on the speakers are at exactly what the amplifier specifies as its minimum impedance than you know it is giving you approximatly the wattage it says. In that case your 2x75wrms amp should have no trouble powering two of those subs.

Be carefull though. If the RMS is higher than the speakers rating you can easily overheat the voicecoils and damage your subwoofers.

Amplifiers are pretty complex and you generally want to buy them to match the subs they are going with. I recomend looking into Ohms Law or taking a basic electrical class if you want a better understanding of Amps.

Answer 3

first off, your amp is small, your subs must be really small, the true power, is 100 watts , if your lucky. get a bigger system....