are all amps equal


I have recently gotten the Mcintosh bug, but a friend of my who does a LOT or reading on the net says power output is the answer not the name. I am looking for the best sound I can get in the 3k$ range for my Usher Be 718s. I have looked at many used Mcintosh units in the 200 watt plus output area, but my friend says a new 250 watt Emotiva would be a better value. The Emotiva is around $800.
I would like some imput.. Thanks, Don
keslerd
Re the question about subs, although it is true that there won't be much to listen to below 40Hz or so, a good sub can be expected to handle the range from say 40 to 80Hz more cleanly (with less distortion) than the Usher's 7 inch mid/low frequency driver. Especially at high volume levels.

Regards,
-- Al
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Tvad - I understand, but shouldn't 42 Hz be fine if somebody listens to jazz or popular music (and not the organs or double bassoon).
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Tvad - it's a trade off. I asked the question because I plan to upgrade my speakers. Getting lower end (lower than necessary?) will cut on definition, imaging etc (within the same price range). In absolute terms I agree (if price is not important). Lipinski 707 speaker is an excellent example of it. They sell sub to go with it but once you get total price there will be another better speaker with limited low end.