Hello All,
I've come into possession of a Melos MA-333, which has a LDR potentiometer (from what I gather these sounded nice but had a ton of reliability issues).
Whomever had this before me took the audio signal from the LDR board and piped it through the Alps pot below the board which was originally used to adjust current to the LDRs and adjust the respective volume (pot was no originally in the audio path).
I've no intention of repairing the board as several PCB traces were cut and it's a bit of a mess. The Alps pot in there now is a 100k motorized Blue Velvet - been trying to find information on how to tear out this board and just replace the potentiometer with a better one (say a TKD for example). I can't quite seem to piece all the information together as some forum members are saying there are some resistor changes I'd have to make in order to switch the board out and run straight to potentiometer (impedance matching?) - doesn't look this was done in the current implementation. The balance pot is also very strange, moving it to either position gives me a distorted left or right channel, not sure what is happening here.
Here's a video of someone who's gone through a restoration of the original volume board and may help provide some guidance to those who's knowledge eclipses mine. It's tough as there are no public schematics for this preamp (or any other of their products). Happy to provide pictures if anyone would like.
Hopefully someone is able to shed some light on what's required to make this happen as the group here has been immeasurably helpful in all of my posts, can't thank everyone enough!
I've come into possession of a Melos MA-333, which has a LDR potentiometer (from what I gather these sounded nice but had a ton of reliability issues).
Whomever had this before me took the audio signal from the LDR board and piped it through the Alps pot below the board which was originally used to adjust current to the LDRs and adjust the respective volume (pot was no originally in the audio path).
I've no intention of repairing the board as several PCB traces were cut and it's a bit of a mess. The Alps pot in there now is a 100k motorized Blue Velvet - been trying to find information on how to tear out this board and just replace the potentiometer with a better one (say a TKD for example). I can't quite seem to piece all the information together as some forum members are saying there are some resistor changes I'd have to make in order to switch the board out and run straight to potentiometer (impedance matching?) - doesn't look this was done in the current implementation. The balance pot is also very strange, moving it to either position gives me a distorted left or right channel, not sure what is happening here.
Here's a video of someone who's gone through a restoration of the original volume board and may help provide some guidance to those who's knowledge eclipses mine. It's tough as there are no public schematics for this preamp (or any other of their products). Happy to provide pictures if anyone would like.
Hopefully someone is able to shed some light on what's required to make this happen as the group here has been immeasurably helpful in all of my posts, can't thank everyone enough!