Hey all! I recently refurbished a Quad FM4 (thanks @johnmath !) that came with this 44. This one also had some faults.
When the tone controls are cancelled out the channels are balanced and fine. When they're activated I get excessive bass out of the right channel, whilst in the left one it lowers considerably. The right channel is affected by the bass switch whilst the left one is completely unaffected by it. All the other tone controls works fine for both channels. Basically, compared to my other 44, it seems I get double the bass out of the right channel with the tone controls activated, whilst it seems the bass is at its lowest out of the left one.
I have performed a full recap of all electrolytic & tantalum capacitors. I have cleaned all switches and potentiometers. I wonder if the switch itself is defective. Anyone has any idea where to look? Cheers for any help pointing me in the right direction.
When the tone controls are cancelled out the channels are balanced and fine. When they're activated I get excessive bass out of the right channel, whilst in the left one it lowers considerably. The right channel is affected by the bass switch whilst the left one is completely unaffected by it. All the other tone controls works fine for both channels. Basically, compared to my other 44, it seems I get double the bass out of the right channel with the tone controls activated, whilst it seems the bass is at its lowest out of the left one.
I have performed a full recap of all electrolytic & tantalum capacitors. I have cleaned all switches and potentiometers. I wonder if the switch itself is defective. Anyone has any idea where to look? Cheers for any help pointing me in the right direction.
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Found and fixed the fault, the switch was physically damaged. The plugs that holds one of the tracks in place had broken off, and the track got stuck somewhere in-between the right and left channel. My first thought was to try to drill small holes in the plastic, and use small screws to put in back in place. But I was afraid of cracking the switch and dealing more damage to it. Instead I glued it with epoxy. Seems to be able to handle the stress. But I'm not going to use the bass control anyway, I'm just happy I can use the filters without having zero bass in one channel compared to the other one which was quite a bit excessive lol.. Anyways, hope this thread helps someone in the future.