Hello,
I have a Mark Levinson 436 that has 21 volts on the output.
Initially the amp had a slight pop when powering on, so I attempted to adjust the servo voltage with R1. When attempting to adjust it to below 100mv the reading was around 3.5 volts. Adjusting R1 would not reduce the voltage, but the voltage actually went up to about 4.5 volts, and would not go down from there. I replaced R1 which allowed this to go down to 112mv. It would not go below that, and now there is 21 volts DC present on the output/speaker binding posts. I have replaced all electrolytic caps on the VG board, but there is still 21 volts DC on the output.
Any help in finding the issue would be very much appreciated.
Thank you.
I have a Mark Levinson 436 that has 21 volts on the output.
Initially the amp had a slight pop when powering on, so I attempted to adjust the servo voltage with R1. When attempting to adjust it to below 100mv the reading was around 3.5 volts. Adjusting R1 would not reduce the voltage, but the voltage actually went up to about 4.5 volts, and would not go down from there. I replaced R1 which allowed this to go down to 112mv. It would not go below that, and now there is 21 volts DC present on the output/speaker binding posts. I have replaced all electrolytic caps on the VG board, but there is still 21 volts DC on the output.
Any help in finding the issue would be very much appreciated.
Thank you.
The amp is now going into protection after switching to On. Protection mode does not activate in Sleep or Standby. I am guessing that it is detecting the DC at the output when switching to On and is activating protection mode.
Any suggestions as to what is causing the DC to be present on the output?
Thank you.
Any suggestions as to what is causing the DC to be present on the output?
Thank you.
Sorry, but that’s absolute nonsense.
With the exeption of the micro processor that never breaks down, all part are readily available or have perfect replacements.
I know from experience what I’m talking about.
It seems almost as if they can only swop complete boards, and yes these boards will be hard to find.
Hans
With the exeption of the micro processor that never breaks down, all part are readily available or have perfect replacements.
I know from experience what I’m talking about.
It seems almost as if they can only swop complete boards, and yes these boards will be hard to find.
Hans
Hello everyone,
I have now picked up the power amplifier from Escoor and found someone in southern Germany who has already repaired several Mark Levinson power amplifiers.
So I'm driving 600 KM to the south at the weekend.
I still have a few questions:
Thanks for any advice, Michael
I have now picked up the power amplifier from Escoor and found someone in southern Germany who has already repaired several Mark Levinson power amplifiers.
So I'm driving 600 KM to the south at the weekend.
I still have a few questions:
- Are there any tips/instructions I could pass on?
- Can I avoid the same thing happening to the second amplifier?
- Can the power amplifiers be placed on top of each other?
Thanks for any advice, Michael
I have only one advise, let them make an offer in advance with a guaranteed maximum price plus a no cure no pay option.
And don’t accept to let them expensively recap the whole amplifier as a precaution which is in most cases a waste of money.
You can’t prevent the other amp from happening the same.
The 400 series is notorious for mishaps caused by a few transistors working outside their comfort zone.
Hans
And don’t accept to let them expensively recap the whole amplifier as a precaution which is in most cases a waste of money.
You can’t prevent the other amp from happening the same.
The 400 series is notorious for mishaps caused by a few transistors working outside their comfort zone.
Hans