@oggioffshore It does indeed have a Tone Defeat switch. I can try taking that out and cleaning it and see what happens. Cheers
@chrisng @jitter I will be honest with you and my skills are pretty much limited to replacing the coils and capacitors, soldering etc etc so with regards to the Ohms and Volts I must say im not sure what I should be looking for.
@chrisng @jitter I will be honest with you and my skills are pretty much limited to replacing the coils and capacitors, soldering etc etc so with regards to the Ohms and Volts I must say im not sure what I should be looking for.
It's always good to eliminate possible causes, but in this case it seems the relay has already been eliminated by replacement.
The headphones output is wired directly to the speaker output with just a voltage divider (R183, R188, R283 and R288) between it and the headphones. This means that the headphones cannot be affected by a bad speaker relay, but it also means it is not protected by it.
The headphones output is wired directly to the speaker output with just a voltage divider (R183, R188, R283 and R288) between it and the headphones. This means that the headphones cannot be affected by a bad speaker relay, but it also means it is not protected by it.
There is a tone defeat switch on the front panel, and I agree that this must also be eliminated as a possible cause.
Ok coolio, ill get onto the tone defeat switch tomorrow morning. Ill give it a good clean and see if it changes anything.
Thanks guys, ill keep you updated. And thanks for being patient.
Thanks guys, ill keep you updated. And thanks for being patient.
Switching it in and out a couple of times may already make a difference. If so, then yes, go ahead and clean it.
I used to have a Marantz amp with a mechanical source selector. It needed to be operated regularly or else oxidation would occur and create similar problems to your's.
I used to have a Marantz amp with a mechanical source selector. It needed to be operated regularly or else oxidation would occur and create similar problems to your's.
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Hi there again. So then a bit of an update. I removed the Tone Defeat switch, gave it a good old clean out. Before replacing it I tried the amp without it in and the distortion in the right channel is still there. The swith actually looked really clean as well. So I think its something else.
What would be the next thing to check
Thanks
What would be the next thing to check
Thanks
Sure, but then you would probably hear it when turning the pot meter.
I'll assume you checked all solder points on the pcb,resold the bad ones if there are.
Signal generator and a scope could be a good thing to use here.....
I'm not an expert myself though.
I'll assume you checked all solder points on the pcb,resold the bad ones if there are.
Signal generator and a scope could be a good thing to use here.....
I'm not an expert myself though.
Just watched another video from someone with same problem. They replaced the resistors, could this be the problem? If so which resistors should I be changing? Cheers
Don't forget that earlier you indicated the amp entered protection mode. I don't believe a noisy pot or switch would provoke that, but an intermittent solder joint might. Try poking, tapping, pressing with a wooden chopstick or similar tool to induce noise.
No and judging by the condition of the switches it seems the problem lies elsewhere. Ill grap a chopstick and start poking
no joy with the chopstick.
One question, is there a way to bypass the tone defeat switch, as in just remove it. I never use it anyways?
One question, is there a way to bypass the tone defeat switch, as in just remove it. I never use it anyways?
If you are able to coax the amp into protection, monitor amp DC output (before protection relay) for possible insight.
Hi htere, I just measured the DC offset from each channel. The Right channel (the problem one) is fluctuating around -4.0 and the left channel is coming in at around +4 which I presume is within good tolerances.
Ive decided to order a new Tone Defeat switch but the original part (SPUN19700) I cant find anywhere. I can find alternatives, 191400 and 191600...
https://tech.alpsalpine.com/e/products/category/switch/sub/03/series/spun/
They are both latching switches, 6 pin but im a little unsure if they would work as i obviously cant find the original spec of the original part so cant compare it?
Any advice here would be superb
Thanks again
https://tech.alpsalpine.com/e/products/category/switch/sub/03/series/spun/
They are both latching switches, 6 pin but im a little unsure if they would work as i obviously cant find the original spec of the original part so cant compare it?
Any advice here would be superb
Thanks again