Help Apt Holman Pre sans inputs left channel

[jeffjeremy]

:tears:

Have a ebay Apt Holman pre that I paid good money for from original user didn't test it for months... Was quoted as very good condition unqote.

Left channel is absent from all inputs, but I believe the problem is fairly new. Noob with tech stuff, have not mess with it but will be using Detox dn5 spray and faberlube soon. Hope to see something when I take a look around. Have the manual/sch. so if anyone can direct me closer to a common/central (left input) source fault please let me know! Any advice is probably a step ahead for my limited experience. The other functions of the channel balance settings seem to be operational.

 

[drumiv]

Try moving all controls back & forth many times, pushing all buttons, ect. I occasionally have an issue like that with mine. The mute circuit is the week point in these. Once sorted out, these are awesome pre's.

 

[DOBIEGUY]

Anytime I've had a problem with my APT it was usually related to the panel push buttons.
They are accessed from the bottom. You will need to remove a few screws to lift the PC board with the little toggle switches. Look for tiny holes on the top of the switches and spray Deoxit in there. Work the switch a few dozen times. Also, service the MUTE
panel button. The mute relay has been a problem from the beginning. Plastic cover is removable---carefully Deoxit too.
While you're in there check all the solder connections where the RCA connectors are mounted to the PC board. The center connection can fail after years of carrying the wieght of many cables and being jammed into cabinets and racks.
Good luck and happy listening!

 

[jeffjeremy]

Yes have worked all the knobs & sw many times, but will try all the above suggestions soon, and hope for the best...

Thks for the info it's much appreciated.

Jeff