Quality inversely related to power output?

All this points to the efficiency of the loudspeaker as being quite important overall

However, this now requires "all other things being equal" in speaker design. It is generally not as easy to find a full range speaker of 100+ db SPL with acoustical performance that is competitive with the many speakers designed between 85 to 91 db sensitivity. (Generally designers equalize drivers downwards to achieve a desirable acoustical performance (crossovers etc.) because the raw driver output is rarely flat and smooth on and off axis acros the frequency range.

The rule I use is to use the smallest amp that will do the job. For example, when I decided to buy a Musical Fidelity integrated amp I had a choice of 4 generations with each generation having more power and more output devices. I chose the oldest and simplest one because although it had the lowest power it still had more power than I would need. But a choice like this is seldom available. I have been looking at the C-J 350 transistor amp. They do not make a comparable lower powered version of it. So it all depends, but if the lower powered amps in a range meet your power needs and they are of comparable quality with the more powerful I would go with them.

In some cases a manufacturer offers two amps with different power ratings, and the only difference is the "rail" voltage (which means a different power supply). Sometimes, but not always, the output transistors may be a different type. But all the input and gain circuitry is the same.

If the quality of an amp is inversely proportional to its power output, then the corollary would be that two amps of equal power are of the same quality. Obviously not true, because power output depends on the connected speaker impedance and the quality of sound depends mostly on power supply, voltage regulation and output devices and the circuit topology that ties them together.

Hi Shadorne, the Classic Audio Loudspeaker model T-1 or T-3 would suit the bill nicely :) My contention though is once the speaker efficiency has fallen below about 89 or 88 db, there really isn't anything out there that is affordable (meaning: under $50K) that will really sound like live music on that speaker.

Live music has power and impact (a live orchestra can easily hit peaks of 115db, something that audiophiles would cringe at in their own living rooms, but that is a discussion for another thread).

Getting those few extra 'gold plated decibels' is the issue. IMO its easier and more effective to start with a more efficient speaker.

And yes, the 'all other things being equal' is also quite challenging. There are so many ways to go about things in this sport :)