Nice job. I have an HA4700 too. I also had to do the repairs and mods in joulespercouloumb's vids (great youtuber, shame he stopped). But cosmetically it is very good. I still have a few switches that give intermittently low input to the preamp chips... the mm/mc selector and filter switches. Where did you source yours? Another problem that doesn't affect the sound is that there is a hum from the transformers.. quite quiet and does not come through the audio. I thought it might be worth changing the smoother caps even though they read ok.
Overall it's a great amp, best sound and loudest I own.
Thanks,
Theo
Overall it's a great amp, best sound and loudest I own.
Thanks,
Theo
I would suggest give them a thorough clean with a contact cleaner. Get it all inside there and operate the switch like 40-50 times. And see how you go. On mine one of the speaker switches went, I haven't tried really cleaning it yet but I do suspect that will see it fixed.
The switch I replaced was because I actually broke it by trying to remove the knob while it was engaged in the "on" position - so be careful not to repeat my mistake. I replaced it with an ALPS switch, the smaller size one. I probably have the model # someplace if you need it but it might take some digging
It wasn't the switch as it turns out (although it did need a clean too) but one of the wires in the loom which runs from the back of the amp to the speaker switch. I traced them out to find the break, patched in a new wire and it's good again.