Class A 30 Watt Amps: Are they enough to drive my book shelfs?


Currently looking at buying a Pass Labs XA 30.5 to drive my Kef 201/2 speakers which are rated at 86 DB sensitivity.  Is this a bad move?
puffbojie
I use a Class A amp that outputs 40 watts but will drive just about anything - they were driving 1 ohm Scintillas when I bought them, and one of the currently drives a pair of speakers that are 86 dB efficient.

I don't know those Pass amps but I do know their reputation and would bet that you would have no trouble driving your speakers with them.
tubes, transistors, transformers, capacitors, ... are all relative to the rated amount of power within certain specs. All are sized to achieve a price point. Other components are designed to deal with ... heat. If an amp truly could produce more power within specs, certainly the manufacturer would publish that capacity. It ain't so. Measured distortion prevents a larger rating.

reserve power not only for instantaneous bursts, move a low efficiency woofer forward, of low and enough power to control the woofer, and, have enough reserve to make repeated instantaneous bursts. Many subs have servo control to assist with the tight control to avoid distortion.

volume controls, preamp components, pushed to high output is not sensible to me. A lifetime of too much heat from high output is also not sensible to me. pushing tubes hard, why?

Play Mickey Hart,, even at mid volume, serious amounts of power is repeatedly needed, serious amounts of control of the woofer is repeatedly needed. 


I've used the XA 30.5 with ATC 85db sensitivity speakers and there was no problem going loud. This amp can put out much more than 30 watts.
More than enough driving my Harbeth 7es-3 (86 db  1w/1m)  with my XA30.5 . As previous post just mentioned and I forgot--the amp goes into A/B at a certain point delivering more than 30 watts and I dont generally need to go past that marker on the dial which shows when leaving hard core class A.