Molnar142
New Member
Looking for some help regarding a McIntosh MC275 MkVI
The other night I was listening at a relatively high volume level (no distortion...~95dB) After about 3-4 minutes there was a very brief crack/distorted sound and the amp shut off. Three front tubes on the right were blinking red.
I gave it a couple minutes and switched the amp back on. It went thru it’s warm up and all the front tubes turned green and the amp played fine. I have not turned it back up to that level that caused the issue and it has not had a problem.
I believe the right channel to be at a slightly lower volume level. (Not positive about that)
I used a non-contact IR thermometer and V8-V10 were running around 265F. V11 (back right most tube) was 160F. Is this normal? I switched that tube out with it’s neighbor in socket V10 and the temp at V11 was still 100 degrees below the others. I switched the front driver tubes right for left and V11 still shows 160F while the others are 260-270F.
I just changed all the KT88 power tubes out with a new matched set. No change, the V11 location is still 100 degrees F cooler.
Your insight and recommendation would be much appreciated.
The other night I was listening at a relatively high volume level (no distortion...~95dB) After about 3-4 minutes there was a very brief crack/distorted sound and the amp shut off. Three front tubes on the right were blinking red.
I gave it a couple minutes and switched the amp back on. It went thru it’s warm up and all the front tubes turned green and the amp played fine. I have not turned it back up to that level that caused the issue and it has not had a problem.
I believe the right channel to be at a slightly lower volume level. (Not positive about that)
I used a non-contact IR thermometer and V8-V10 were running around 265F. V11 (back right most tube) was 160F. Is this normal? I switched that tube out with it’s neighbor in socket V10 and the temp at V11 was still 100 degrees below the others. I switched the front driver tubes right for left and V11 still shows 160F while the others are 260-270F.
I just changed all the KT88 power tubes out with a new matched set. No change, the V11 location is still 100 degrees F cooler.
Your insight and recommendation would be much appreciated.
