Confused about power output of T-Amp

[infinid]

I have read a bunch on the tripath chip and the t-amp, but the main thing I cannot resolve is the output power. I do not see how the 5-10W that amp generates per channel is enough to power some of the speakers that people are using them with. Specifically in the 6moons review they use the amp on fairly large speakers, and do not comment on it being a problem.

I have a pair of Mission M34i floor standing speakers. According to spec they are fairly efficient at 92dB. But the spec sheet says the power range should be 25-150W (nominal impedeance of 8 ohms with a minimum of 3.8). Even if I bi-amped each speaker (they have two woofers) I still wouldn't reach the minimum power reccomended.

Do you all have much more efficient speakers than this, or am I missing something?

[Pano]

Originally posted by infinid
Do you all have much more efficient speakers than this, or am I missing something?

You are "missing" something, but it's not uncommon. Speakers are not like cars. Many people think that big speakers need big amps, just like big cars need big motors. But usually the opposite is true. Big speakers tend to be more efficient than small speakers, so they need less power. However, big speaker can usually handle more power than the small ones. That's good.

Have a look at speakers used in Pro Sound. They are very sensitive, often over 100dB/W. And they can handle 100s of watts. But is you put them in your living room, they could get very, very loud on just a few watts.

The average T-Amp puts out about 7.5 watts RMS into 8 ohm, before clipping. That's not a lot. But with your 92dB Missions, that can still be pretty darn loud in an average size living room. The specs for your speaker are just a good guess from the guys at Mission. There is no real minimum, but more power = more volume, for sure.
Each time you add 3dB to a speaker's sensitivity, you need 1/2 the power. E.G. if for a certain level you need 12W with 89dB speakers, you would need only 6W with 92dB speakers. More sensitive speakers tend to sound more dynamic, too.

At work I have a pair of 2 ways that are about 94-95dB/W. The T-Amp does pretty well with those in a huge space - almost 50,000 cubic feet!

Bottom, line. Your 92dB/W speakers should work well for the T-Amp in a not too large space. Say 2500 ft. cube, or less. The bigger the space, the lower the sound level.
More sensitive speakers will give you more level, more dynamics.