I just got out my magnifying glass and looked at the transistors in the EQ. They are 2N5088, 10 of them. They cross to NTE123AP. Oddly enough the 2N2222 I spoke about earlier is a direct cross to the NTE123A transistor. I can't see much difference between the "A" and "AP" versions. I found some NTE123AP transistors on Ebay and they are on the way. So I guess my memory is good on what I saw about the 2N2222 as replacements but decided to go with the "more direct" replacement. Thanks to andrelebon also for his response.
They don't wear out so I am not sure why you would replace them? The only justification would be if one was actually bad.
FWIW I would choose NTE parts dead last of the options available, and since the original is still available I would use that type.
Electrolytics are a different matter, all should be replaced.
FWIW I would choose NTE parts dead last of the options available, and since the original is still available I would use that type.
Electrolytics are a different matter, all should be replaced.
+1 Transistors don't age like tubes. They can become noisy but other than that they either work or they don't. Nothing gained by replacing otherwise good transistors.
If you really want to improve this unit, I would redesign with good modern audio OPAMPS. Of course you will need to know the response curves.
-OR-
Duplicate the operation with a MiniDSP card.
If you really want to improve this unit, I would redesign with good modern audio OPAMPS. Of course you will need to know the response curves.
-OR-
Duplicate the operation with a MiniDSP card.
Last edited:
Before years, I did all this replacements,
Resistors, capacitors and ... transistors.
I don't remember the brand of transistors, but my choice was some BC... the most silent.
And, don't expect some huge difference.
I think, the most important part of the work, is the choice of capacitors.
So, change just them, an don't waste time and money.
Resistors, capacitors and ... transistors.
I don't remember the brand of transistors, but my choice was some BC... the most silent.
And, don't expect some huge difference.
I think, the most important part of the work, is the choice of capacitors.
So, change just them, an don't waste time and money.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.