help w/amp demo

How can I determine if the amp is being strained? Or, should I just listen for bass and dynamics?

Thanks.
Shredder (Answers)

Just compare it to what you're used to hearing with the Classe amp on dynamic material. You'll know if the music sounds right or not.

BTW, I was impressed with the 50A amps. In fact, I contacted Kara yesterday, but I don't think the situation is going to work out for me (no local audition, etc).

What a way to go. Wish a had a 'Sounds Real' type dealer in my area, one that comes to your system. That is the best way to determine whether a significant improvement in your system sound can be achieved.

Excellent suggestions by Tvad, as usual. The one thing I would add, with respect to your question about having enough power, is that a key variable is the dynamic range of the music you listen to.

I also have 90db speakers, in a 13 x 20 room, with the listening distance being about 9 feet. I am currently using an 80W tube amp (keep in mind that is only 3db more than 40W). On well recorded, minimally compressed, wide dynamic range classical symphonic music (which I listen to a lot) I find that the 80 watts is adequate, but just barely. A small nudge on the volume control above the position I normally set it to will result in slight but noticeable clipping.

On virtually all other kinds of music, listening at loud but sensible levels, the 80W is very easily adequate. A possible exception being things like some of the 1980's Sheffield Labs direct-to-disk LP's, some of which have dynamic range that is not likely to be encountered elsewhere. I haven't listened to those yet since I replaced my 200W solid state amplifier, which could handle them easily with the 90db speakers.

Best of luck!
-- Al

Additionally, the sensitivity rating of the speaker can be less of an indicator than the impedance curve or consistancy. Tubes do best with a fairly flat (or certainly not wide fluctuations) with the impedance load. I don't recall off the top of my head how the curve on the Ariels is. If it is a fairly flat curve, you are probably okay. Of course, for $450 you can look into a Paul Speltz autoformer which is supposed to help to address this (at least from what I understand of it).

Thanks a lot everyone. Very helpful.

BTW, I listen to a wide variety of music from Rock to Jazz to Funk to World. But, no classical. I get the impression that the dynamic limitations of a less powerful amp may be less of an issue for non-classical music, which is less dynamic?