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Luxman LV-104u service manual

I have a Luxman LV-104u which is defective. On this website I only find the service manuals of the models 103u and 105u though, so I'm looking for the service manual of the 104u. I have seen that the 103u and 105u differ quite a bit in their electronic design, so which one (the 103u or 105u) would be closest to the 104u's design electronically ?



Luxman LV-104u service manual

The LV107U is more compatible with the 104.

Luxman LV-104u service manual

Thank you. I found out there is a service manual available on the internet that covers both the 104 and the 107. I managed to repair this amp and restored it to its full glory again by thoroughly cleaning it. The fault was double: several bad solder joints on de PSU-pcb and a design flaw in the tone control circuit which causes the DC-working point of the opamps to shift violently when the (bass) control potentiometer develops a less than optimal contact (as they all will sooner or later due to normal wear of the carbon track). Since the owner did not use the tone controls I bypassed this circuit altogether as the potentiometers used are very special (and fairly low quality) and hence almost impossible to find.