Do amps have a sweet spot?

06-16-13: Csontos
"So... is it usual for an amp not to open up until you start pushing it?"

I don't know how "usual" it may be, Peter, but I certainly wouldn't be surprised if is an effect that is present to an audibly significant degree with many amplifiers. Albeit without a great deal of predictability.

For one thing, as Ralph (Atmasphere) has said in past threads certain odd order harmonics can, even in trace amounts, significantly affect our perception of loudness. Therefore variations of an amplifier's distortion characteristics that may occur as a function of signal level can significantly affect perceived dynamics.

For instance, if those particular odd harmonics are present to a greater degree, relative to signal level, on musical peaks than during soft passages, there will be a perceived increase in dynamics. And if the volume control is set lower the differences in distortion between musical peaks and soft passages may become smaller, resulting in a perception of lessened dynamics.

Also, of course, the operating temperatures of transistors and other circuit devices will be affected by the volume level, with all kinds of subtle sonic consequences being conceivable.

As I and others said earlier, though, in any given situation lots of factors unrelated to the amplifier could conceivably come into play, perhaps to a much greater degree, including the Fletcher-Munson effect and the behavior of the speakers .

Best regards,
-- Al

I wasn't taking you to task. Just pointing out the op's query. Seems it got lost. I knew you'd come through.

Every component has a sweet spot so to speak. This is where "synergy" comes into play. It's more than just the ideal operating point of a single component rather when all the components in a given system work together at their optimal levels to produce the best sound a system has to offer.
Lets say you have a perfect mate (okay, great match) between an amplifier and speakers. If the preamp is not a good fit to the amplifier (or amplifier speaker combination), you may blame the amp for the system's downfalls. Volume may get too loud prematurely or you may have to crank the volume to get the speakers to play at normal levels.
With an integrated amplifier that has been designed properly, this should not be an issue if matted with the proper speakers.

The general behavior of all my amps is the same whether it's a 45 wpch amp or 800 wpch amp. I don't start hearing prominent inner mid-range detail until the amp is 'cookin'. Does this not stand to reason? Why would I design an amp not to perform it's best at rated output? Nothing is perfect. The whole technology is rife with compromise.