Too Much Power

Too much class A power creates unnecessary heat.  In a class D amp (or generally class AB) there is no real practical drawback. 

You might find that an amp that is designed to put out 600 wpc didn't focus its design on making the first 5 watts (where you will be listening the most) the best that they can be.  I currently use a 6 wpc amp, just for that reason.

The power rating of 600 wpc into 8 ohms and 1200 wpc into 4 ohms is the mark of a good quality amp… as far as power. Also, there is no such thing as too much power…. Assuming you don’t crank up a little set of speakers to ridiculous volumes.

However, there is a question of the sound quality of the amp… each amp type independent of power has a character (design type and importantly the designer)... is that the character you want? For me, high quality tube amps give me the quality of sound that I want. So, it would be hard to afford an amp with that much power… on the other hand, my amp produces 140wpc in linear mode and 70 wpc in triode mode. My Sonus Faber Amati Traditional sound best with the lower 70 wpc triode power.

So, as far as an amp… the character of the sound is most important… then, more power is better. 

i have a mcintosh mc602 amp with 600 watts per chanell at 2 ,4 and8 ohms!! where doe's my amp stand???

russ69 - Understood. Thanks.

ghdprentice - Thanks for insight.

Beyond a certain level, maximum power output (taken by itself) is not a very useful measure. Even prior to the class D era, there were plenty of power amplifiers used in pro audio that had hundreds of watts output, were comparatively cheap, and sounded pretty horrible. Power supply quality, component quality and consistent (e.g. transistor matching), the overall design philosophy and circuit layout and manufacturing quality are all influential. My current amplifiers are the lowest powered (120 w/ch into 4 ohms) that I've had in my system for a long time - and they sound the best so far.