Odd things going on with a Marantz PM500

Hmm... I would not use a socket but simply solder and then stand the IC up, in other words carefully bend the legs 90 degrees. Now you only need a single wire to pin 8. pins 5, 6 and 7 can be linked super neatly on the chip itself.
 
oh well a bit late for that , but this is how it will look.At least this way it can be replaced if anything goes wrong, and i think it looks neat too
 

Attachments

  • IMG_20231104_112619.jpg
    IMG_20231104_112619.jpg
    267.6 KB · Views: 47
so first one done and it works a treat
might just tidy the underneath up a bit, but it isnt too bad
rails were still too high with 220k so i played around a bit and settled on 100k
so rails are +/-18.7v
 

Attachments

  • IMG_20231104_131548.jpg
    IMG_20231104_131548.jpg
    476.8 KB · Views: 58
  • IMG_20231104_131606.jpg
    IMG_20231104_131606.jpg
    138.9 KB · Views: 53
so thanks again @Mooly
Ive realy learned alot with this one, proberbly more than anything so far.

I had an issue with the second one, and although it was working , i only had 6v on pin 8, so i had lost one of the rails

so i assumed, as it was working but distorted, it was working as a half rail, and this was causing crossover distortion?

i found the issue anyway it was broken print

I think it looks quite neat

so all done 🙂

now to try it out on my speakers in the lounge👍
 

Attachments

  • IMG_20231104_155731.jpg
    IMG_20231104_155731.jpg
    413 KB · Views: 52
Your right it would have been. But if you notice the first one I moved up into space where some of the components that were not required left space, and I was able to use the original pin positions 1 to 4,but to enable me to do that on the 2nd would have meant moving resistors and caps, so the second one is 100% wired underneath
 
That side of things should all work just the same if you were to leave the resistors in place, however the Laterals do not need those 0.33 ohms as you know with the NAD's. I would just leave the transistor, if you link the 0.33 ohm out then the transistor is permanently off.
 
I think the 10's will be just fine. A single pair is good for 100wrms at rails higher than the Marantz uses. Heat is the big problem with any amp and that is actually higher with the double die parts because you should bias them to twice the value of the singles.