Marantz 4430 Receiver - Phono distortion - Fuzzy sound

[redpackman]

Played the 4430 today. Playing LP's. They sounded good for awhile and then the sound became distorted in the right channel. Fuzzy sound. With no record playing one can hear the fuzzy sound in both channels. But when playing the LP's the distortion is only in the right channel. Perhaps the left is bad too, but it gets overpowered when signal is introduced.

Solder joints need to be reflowed? Bad/noisy transistors in the phono section?

Important note: when playing CD etc. through AUX section it all sounds wonderful. So, bad phono section?

Any suggestions would be appreciated.

 

[Leestereo]

The Marantz phono stages of this vintage often used the failure-prone 2SC458 transistors; these should be replaced with KSC1845 transistors (note that the pin-order for the original 2SC458 is "BCE" whereas that for the KSC1845 is the common standard "ECB").

 

[rBuckner]

Yup to the above as a starting place and quite likely will do the job!

 

[catrafter]

I replied to your post in DIY.
This is the best place to get help on Marantz gear.

Tom

 

[redpackman]

Just to clarify a couple of points. Put in some KSC1845's and now the unit sounds GREAT! Played it for some time to test it out too. This time, no distortion. Thank you for all the help.

One final note: The KSC1845's I installed did have a reverse pattern from the 2SC458's that were faulty or failing. I checked some data sheets and they seemed to indicate that the 1845's would have the same pattern as the 458's but I'd been warned by an Audiokarma Super member Leestereo that the pattern would be different. I checked the 1845's with a tester I had and indeed they were the reverse of the 458's, at least the ones I got. So I installed them in a reverse of the 458's and they indeed did, as you can see above, work perfectly. Thank you Leestereo. Yet, what's up with the significantly differing pin pattern?