Oh yeah, could have been worse. I wonder now if that could have affected the heat transfer from the transistors to the heat sinks.About 12 inch/lbs..Be glad they didn't use epoxy ..
Yamaha M-50 restoration /recap kits on eBay
- Thread starter RoddyRod
- Start date
Sparkplug
Super Member
You bet it did … just another case of audio gear vandalism under the pretense of restoration … LOL
It has been a while ,but with the holidays, work and life I finally got around to finishing up this project. I ended up replacing the output transistors with some sanken equivalents ,the drive transistors with some of the onsemi equivalents.They may not have needed it, but since I was replacing the power transistors from the same heat sink, might as well. All the electrolytics replaced with the best nichicons I could find and those bigger power caps replaced with those elna 15000mfd values. Adjusted the power supply voltage first and the photocoupler voltage, they were pretty close to what they were supposed to be as is. The idle adjustment was a surprise to me, it was a bit higher than I would've expected since I didn't adjust or mess with any of the variable resistors on any of the boards. Adjusted the bias very little on both channels to get them into spec and we were off to the races.
It sounds really good so far! I have let it warm up a few times for the past week while playing some loud music and it really jams! At no time has it cut out on me like it did with the previous owner. But I have some suspicions they have worked on it before like I have mentioned. Soon I am going to install it into my system and compare it to the marantz I am running now.
And a Happy 4th of July to everyone!
It sounds really good so far! I have let it warm up a few times for the past week while playing some loud music and it really jams! At no time has it cut out on me like it did with the previous owner. But I have some suspicions they have worked on it before like I have mentioned. Soon I am going to install it into my system and compare it to the marantz I am running now.
And a Happy 4th of July to everyone!
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that more likely is assembly glue used to hold the parts in place prior to going to wave solder. Yamaha used glue sparingly. Other manufacturers really glopped it on.