Jolida music envoy monoblocks

[erfmd]

Good afternoon all. I have developed a "hum" in one channel and suspect it may be somewhere in the internal power supply of one of my monoblocks (jolida music envoy.). I have scoured the internet trying to find schematics without success. Any suggestions? They sound beautiful when functioning properly and were not cheap so I hope to be able to get them repaired. Any advice would be greatly appreciated. Thank you.

 

[geespot]

Did you contact Jolida (Black Ice Audio)?

 

[spantou01]

Why do you suspect the power supply? Could be a tube that became noisy. I don’t know how skilled you are in working on tube amplifiers, but a solution will be found. As @geespot advised, try Black Ice for the schematic.

Meanwhile, have you tried to switch tubes between the amplifiers and recheck for the hum? One stage at a time starting with the input tube(s) working towards the output tubes. Take care with the pair of output tubes (211, right?) as they may need to be rebiased. If the hum stayed at the same side you have now ruled out tubes as the source of the problem.

 

[erfmd]

Thank for your replies. Will try that and check out black ice audio.

 

[cademan]

Why do you suspect the power supply? Could be a tube that became noisy. I don’t know how skilled you are in working on tube amplifiers, but a solution will be found. As @geespot advised, try Black Ice for the schematic.

Meanwhile, have you tried to switch tubes between the amplifiers and recheck for the hum? One stage at a time starting with the input tube(s) working towards the output tubes. Take care with the pair of output tubes (211, right?) as they may need to be rebiased. If the hum stayed at the same side you have now ruled out tubes as the source of the problem.

Remember these are separate mono amplifiers each with their own power supply.

 

[spantou01]

I do remember it, but how is your statement relevant to what I suggested?

 

[Mr Boochie]

Thank for your replies. Will try that and check out black ice audio.

Trying removing and replacing each tube, one-at-a-time. This action may clean the pins. If you have some electronic contact cleaner, you can try a little on the pins.

 

[cademan]

I do remember it, but how is your statement relevant to what I suggested?

Reading your post, to me I thought that you had thought that they were one piece amplifiers. I didn't mean anything crass by my comment so no need for snarkyness!