[desik]

In general I've seen amp specifications have just one maximum power number, regardless of gain settings. Does it apply to maximum gain only or to all of them?
 
Burson sales rep said for example that on Soloist SL low gain offers only 100mW, while amp official rating is 2W. This doesn't make much sense to me. LCD-2F sound exactly the same to me on both settings when adjusted for volume. And LCD-2 by all accounts wants more than 100mw. I'm generally listening at low volumes.
 
Conversely, if the volume never goes beyond 25% on my amp, does it make sense to use a higher gain setting?

 

[Music Alchemist]

Low gain just makes it so that on any given volume setting, it will use less power than it would on high gain. This can be useful for sensitive headphones that get too loud too easily on high gain. Most amps won't sound any different on either setting when adjusted to the same SPL (loudness) level, so it's rarely something to worry about. Naturally, the maximum output power spec is on high gain and at max volume unless otherwise specified.

 

[drarthurwells]

An amp's rating of 2 watts is useless info.
 
Is this peak power sustained only in a few milliseconds or is it continuous (RMS) power over the 20 Hz to 20 KHz  frequency response as sustained indefinitely..
 
Then at what impedance is the RMS rating, 4, 8, 16 or 32 ohms (or higher)?
 
A HP rated at 100 ohms with a sensitivity of 97 db per one milliwatt needs only  about 16 milliwatts of RMS power at 100 ohms to adequately drive it, but some amps can not produce this much power. 
 
 
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