Noisy electronics on early Yamaha TRB

[mcc]

Hi guys,

I recently picked up a slightly worn but overall very nice TRB4 (JJ pick-ups bolt on) and am loving it. I had read before getting it that many people complained of noisy electronics and I do think it has a hiss that is loud even for 90’s standards. From what I read, many people simply upgraded the electronics.

I wondered if anyone had pinpointed if it was the pickups or the circuit or both.

Also, I’ve read that changing this or that capacitor might help for hissing problems... has anyone tried it?

best,

Marcus

[ikay]

Single coil pups will add hum not hiss so sounds like the preamp. Later versions of the Mk1 had SC soapbars with a dummy coil. Does it hiss with the eq set flat or only when boosting the highs? There are output level and eq adjustment controls inside the control cavity, might be worth having a play with these to see if it makes any difference, if you haven't already.

[mcc]

Its definitively not single coil hum and according to the specs it has stacked J pick ups. Its an underlying hiss that increases when you turn up the highs. I found that overall output is very low so I cranked up the output inside the control cavity. Maybe I went too far.

Anyone out there replaced the electronics only?

[BILL POSTERS]

Something in the back of my mind says they used TLO62 op amps.

Try warming them up, tip of a soldering iron or a hairdryer. if the hiss gets worse, and if your up to it replace them. or just replace them anyway, theyre probably only pennies each.

Not sure but I think RS stock a FET replacement which should be quieter and draw less current from yer batteries, someone on here wil no doubt be along in a minute with more knowlege than me about that.

[mcc]

You are right about it using TL062... two of them. The board us a bit cluttered for me to give it a try. And any money I have to spare I think will go into a fret dressing...

thanks for the comments. Maybe a gather up the courage to change the op amps some time in the future.

m.

[quote name='BILL POSTERS' timestamp='1447860056' post='2911017']
Something in the back of my mind says they used TLO62 op amps.

Try warming them up, tip of a soldering iron or a hairdryer. if the hiss gets worse, and if your up to it replace them. or just replace them anyway, theyre probably only pennies each.

Not sure but I think RS stock a FET replacement which should be quieter and draw less current from yer batteries, someone on here wil no doubt be along in a minute with more knowlege than me about that.
[/quote]