amp and speaker watts

Jun 24, 2016
I am trying to match the amount of watts from my amplifier to my speaker, the wattage of the amplifier is 150. I have two pairs of speakers to connect to the one amplifier, if i want to make the wattage of the speakers 150, do i have to get two pairs of 75W speakers or two pairs of 150W speakers.
Matching amps to speakers is more involved than just matching the simple numbers. The ratings themselves may be questionable since some manufacturers are sort of optimistic if not out right lying. Others are dead honest.

If your amp is 150 watts per channel into 8 ohms it may produce up to 300 watts per channel into 4 ohms and up to 600 watts per channel into 2 ohms. Each amp is different (some produce less or the same power as the impedance goes down because they are not stable enough or produce enough current to drive the lower impedance load.
If the speakers you chose are 8 ohms each and your wire them in parallel then the amp will see 4 ohms so how the amp handles 4 ohms will be important. If they are 4 ohms each then your amp will need to perform well into a 2 ohm load when the speakers are connected in parallel.
Speakers can be connected in series which will double the impedance and half the power of the amp. A series connection will compromise the bass quality with most amps so is not the best way to go.
For compatibility purposes you generally want your amp to be in the upper part of the speakers suggested power range. You can go a bit over. Going a lot over is wasteful and may lead to blowing up the speakers. You can always go lower than the max rating and that is fine if the added power would just play the speakers louder than you would ever use them. If you try to get more power out of the amp than it can provide into the speakers you can damage tweeters with clipping distortion or over heat the amp and maybe damage it too.