Does the heat an amp puts out have any effect on the sound quality ?


Does  how hot an amp runs have any effect on sound quality ?
Or is this only a concern for the longevity of the amp? I have an old Harmon Kardon
amp that supposedly puts out 60 watts at 8 ohms and has 30 amps of current.
when purchasing I was comparing it to  an onkyo with 120 watts. They were driving
a pair of jbL monitors. It flat out smoked the onk. Probably twice the volume.
I decided On a minor upgrade down the road to a Yamaha as-500 at 85 watts.
Years later I got tired of the brightness of the Yamaha. Decided to hook up the Harmon
kardon just for kicks. Instantly the mains came back to life. Much cleaner an  better bass  maybe
a little more volume. Its almost like harmon Kardon put a wrong part in this amp. Making it sound much better than it should. My only concern is how hot it runs. It doesn't seem to effect anything even
at long listening periods. Should I be concerned at how hot it runs. It has given me no problems.
Any one have any opinions ?
128x128jcb1957

Showing 1 response by rlawry

I think heat is a byproduct of the amp design.  With a Class A amp each output device conducts both half waves, so it runs full out all of the time, dissipating what current is not sent to the speakers as heat.  The higher the speaker output, the less the heat output.  The heat itself will probably not be an issue, but I once had an OTL amp that put out so much heat that it eventually damaged components inside the amp, so it was a reliability issue.  Most amps are well enough designed to avoid this problem.  You probably found through your amp experience that watts are not necessarily watts and that current is the real factor that affects how loud the system will sound.  I would bet the HK to have a much more robust power supply and it probably weighs more.