BA312 noise?

[The Fuxtor]

Just curious if anyone has had static crackling noise from failing ba312 chips? Or do they just fail and drop a channel?

 

[Hyperion]

failing ba312 chips?

I haven't seen many BA-312 equipped units, but in my experience they just go noisy - i.e. excessive white noise.

 

[aldena007]

Encountered them on 9090/9090DB. Can cause a dead channel if one of the two [or both] on the tone control board dies. The phono amp uses two 312's.

 

[The Fuxtor]

Consensus seems to be , hissy white noise or lost signal. This unit I'm into has had rebuilt driver boards and starts intermittently crackling still ( noisy transistor noise?) New transistors on preamp, protection and amp boards? I think I can rule out the BA312 chips

 

[absolve2525]

Just curious if anyone has had static crackling noise from failing ba312 chips? Or do they just fail and drop a channel?

Yes. Happened on both my Sansui 890DB/8080DB and Marantz 2275. Crackle sounds I couldn't pinpoint. I put Sparkos Labs replacement boards in my Marantz and sounds excellent. Less floor noise and no damned crackle sounds. The Sansui got a replacement BA312 on one channel and works fine now. I would put Sparkos in my Sansui also if I ever have BA312 issues again.

 

[PF Sound]

I bought the 10 unit build-your-own replacement kit from AforA on the bay. Pretty cost effective way to replace those original units on the 9090/DB's since there are 5 in each one. I don't bother doing the mic board, so just 4 per unit.

 

[absolve2525]

I bought the 10 unit build-your-own replacement kit from AforA on the bay. Pretty cost effective way to replace those original units on the 9090/DB's since there are 5 in each one. I don't bother doing the mic board, so just 4 per unit.

How do they sound? I have looked at those for possible future needs.

 

[PF Sound]

They don't "sound" like anything, which is good. They're easy to build & small enough to fit where they need to. I bought some 90* header pins in rows of 40 I believe, & if you snap off 7 they fit the little boards perfectly.....makes it easy & neat but you have to plan a little ahead to fit them where you want in relation to other components compared to just using snipped off leads from components. For instance, when you replace the 312's on the tone board it ends up being a tight fit with the main filter caps.