wrote in message
oups.com
Hi, I recently bought a HK A500 from ebay and would like
to know something about this amp...
1- I noticed that itīs very weak in power, I use it with
a pair of JB L Jubal, I have to listen beyond the midlle
(1 or 2 o clock) to hear in a good volume, is it right?
Volume control position versus loudness is a poor test of power output.
2-One transformer was changed, the channel B, how can I
see if the job was well done?
If the transformers are visibly different, then it wasn't an exact
replacement.
Note: this was not one of HK's best efforts, even in the days of tubes. The
OPTs rolled off the bass.
3-I noticed that at this channel B when I turn the
balance to only this side, the treble increases, what can
be the problem?
Who can tell? There's a reason why I have test equipment on my bench, and
looking pretty ain't it.
4-the ambience function is not working, what it is the
funcion of this? How can I repair?
The schematic posted here
http://intra.engr.uark.edu/~lar/fireamps.html
Says that there is a separation control, but no ambience control. It's
basically a sliding stereo/mono switch. It's effect might be subtle enough
that you're not hearing it with speakers.
5-there are two OUTPUT BAL controls near the tubes, one
for each channel, what are their purpose?
I seem to recollect that you are supposed to adjust them with a test tone
and a THD analyzer. Got either?