OK cool just thought I'd check. Seems the bass boost has some relation to it.
No audio with no pot has me a bit worried.
The pot was cracked on the underside though so it was definitely faulty.
It may have taken more components out when in failed. Hence no audio 🙄
New pots will be about 2 weeks away
OH OK like I said I don't know much about the pre amp section.
Well that gives me a little hope that the new pot may fix the problem. Fingers crossed.
The Amp still goes into protect when u cycle between Master and slave and a loud pop through the speaker. This may be normal I'm not sure. But when it was in slave mode turning the bass boost would not cause protect so its definitely a problem in the pre amp section
So it's not normal to go into protect when u cycle between Master and slave. Just tried it on the other amp and no pop or protect on that one
Does anyone know a way to test these 4560d chips in circuit? Is there a specific voltage that should be on pins?
I notice there should be input voltage on pins 4 and 8.
I notice there should be input voltage on pins 4 and 8.
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For the most part, except for the power supply pins, the voltage should be very near 0v if the power supply pins have a split supply (±15v).
In the manuals for some amps, they tell you to turn the amp off because there is a risk of popping when making changes but it's rare nowadays. A loud pop is generally due to a defective op-amp with excessive DC on it's output terminal.
In the manuals for some amps, they tell you to turn the amp off because there is a risk of popping when making changes but it's rare nowadays. A loud pop is generally due to a defective op-amp with excessive DC on it's output terminal.
Yeah I'm getting a good 23v DC across all the Power pins. I just wanted to see if they could have been part of the issue.
Aside from that. Could it be a bad capacitor in the pre amp section that somehow filters out DC voltage?
Highest was 22.5vDC and that was on both a and b outputs of this 4560d.
All the rest were 11.5v and 1.2v
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For most all audio circuits, the op-amps are operated from a ±15v supply. The negative supply terminals are connected to the negative 15v supply. Not to ground.
OK so where should I put the black probe if not on the vcc-pin?
Oh sorry I think I understand now. Connect black probe to ground?
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10.7vDC is what I get. But most the IC chips are not putting out anything.
I got 10.7v on both a and b of the top chip I posted a photo of earlier
The one below that is 6v and nothing.
Below that 10.7v and nothing
Below 10.7 and nothing
1.3v on b output and nothing on a to the one to the right.
Then from there. Nothing
I got 10.7v on both a and b of the top chip I posted a photo of earlier
The one below that is 6v and nothing.
Below that 10.7v and nothing
Below 10.7 and nothing
1.3v on b output and nothing on a to the one to the right.
Then from there. Nothing
None of the op-amps should have any more than about 25mv. There's no exact number but a volt or more for any op-amp in use (sometimes only half of the op-amp is used) is likely indicative or a problem. To know if an op-amp is defective, you have to look at the voltage on the op-amp input terminals and see if the output is what it should be for the two input voltages.
The following page will help you to understand op-amps:
Operational Amplifiers
The following page will help you to understand op-amps:
Operational Amplifiers