Is there any truth to this question?

I think the power would drop to 27 watts on the 4 ohm tap driving 8 ohms (roughy) - in fact that is the way I use them with the Merlins - light loaded. Lower distortion, less stress on tubes, and more peak power for transients (not sure why, but Roger says it is so).

02-13-12: Mapman
If an amp is clipping, there is a good chance the sound quality is negatively affected well before any any clearly audible distortion is noticed. Better to have an amp that goes loud effortlessly to provide headroom before any clipping comes into play. One might be surprisec what is needed to do this for less efficient speakers. The difference can be subtle but very significant. With the exception of very efficient switching Class D amps, some weight and size is usually required.

Completely agree Mapman.

I am of the opinion that most audiophiles underestimate the amount of power they need.

30 watts of power might be adequate to reproduce music at average levels for a typical speaker /room, but musical peaks can require 10x average power.

Most audiophiles simply don't recognize when their amps are clipping. This is because the clipping usually only occurs on musical peaks where it is very transient, and does not occur at the average power level. Transient clipping is not recognized as clipping by most listeners because the average levels are relatively much longer than the peaks. Since the average levels aren't obviously distorted, the listeners think the amp is performing within its design parameters -- even when it is not...

Kiwi,

I suspected this was the case but it was only once I pulled out all stops and went with the 500w/ch Class D BelCanto Ref1000m monoblocks that I became convinced.

I've had several amps in my rig prior with the relatively hard to drive OHMs and Dynaudios up to 200w/ch or so. The BCs are the first to always play effortlessly at any reasonable volume with no signs of running out of gas. Effortlessly means transients are clean and crisp even as the volume goes up.

I did have a 360w/ch Carver amp originally that went plenty loud enough, but that amp had Carver's tube transfer function technology and did not have the guts to drive the current hungry OHMs or Dyns as well at any volume.

I cannot think of any speaker that is so inefficient that one would be listening to it at an average output of 30 watts so that a 10 db peak would require 300 watts.

Yes, with inefficient speakers something more than 30 watts may be needed where one listens at very high average levels as a safe margin to avoid clipping. But, that does not appear to be the practice of the original poster. If that margin came for "free" then of course go with higher power. But, nothing is free--one has to compromise other aspects of performance. Yes, it is possible that a whole new technology may come along and erase most, if not all, of the compromises need to deliver high power, but I've not heard it yet.

It certainly is not, in my experience, Class D switching amps. It is too early to predict where further improvements in that technology will take performance of that technology, so there is hope there, but right now, the amps I heard fall short of the best conventional solid state gear.

It is a matter of personal preference and priority. For me, good performance at low volume levels is a high priority and the ability to deliver satisfying detail, weight, and dynamic contrasts at low volume is more important than high volume performance because I very rarely want to listen at head banging levels.

I know people often do calculations of power needs based on supposed real life concert levels. Those calculations don't reflect practical use of a system. Classical music has a massive dynamic range, so, in theory, a lot of headroom is needed. But, in reality, recordings NEVER deliver the dynamic range of a real concert (probably most listeners would not like a realistic range because the music would be too soft in quiet passages). If one set the volume level at peaks to match concert level peaks, the average level would be unrealistically loud. As for rock music, I hardly need my system to play at concert level to get the juices jumping. If my system did not sound WAY better than any live rock concert and if it needed to be played at anywhere near live concert level to sound good, I would junk it.

I have found that, as my system has improved over the years, I want to listen to it at lower, not higher, volume levels.

"It certainly is not, in my experience, Class D switching amps. It is too early to predict where further improvements in that technology will take performance of that technology, so there is hope there, but right now, the amps I heard fall short of the best conventional solid state gear."

Larry, is that an opinion or do you have some facts to support?

My experience is different. Personal preferences may result in not liking Class D, or Class D may not always integrate well with the rest of the system, like any amp, but my assessment is that the performance can be competitive with other amps I have heard in other very good systems.