• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Marantz 2270 Crackle

Yoast

Yoast

New Member
I have a hiss or crackle or static on both channels (but not at the same time) when using the marantz 2270. I switched the cables left and right channel and the static appeared on both channels. (not simultaneously) The amp was recapped and serviced just recently because of this but the technician could not find any problem and now it has come back. Ironically the person I bought it from had it recapped as well (a year ago- with shitty caps) so I had it checked just in case and the technician I used replaced the caps with ELNA caps.

When I touch the main in pre out jumper on the back of the amp it gets worse and I can produce it. Also it happens mostly after warmup or around half an hour of playing and It happed when I moved the speaker wire as well.

What can it be?

Thanks!
 
Register to hide this ad
Don't know the amp, could it be bad solder connections on the pre-out/main-in RCA's?
If you connect an iphone(or whatever) to the main-in do you still get the crackle?

By saying the crackle does not appear simultaneously on both channels suggest not a power supply issue.
Should check if amp has any noise prone transistors, there's a list on Ak somewhere.

edit best to move this thread to the marantz subforum, great expertise there.
 
Thank you for your insight.

If a moderator can please move this to the Marantz subforum, I would be grateful!
 
2270 has 2sc458 transistors on the phono board. These are known to get noisy. You say it happens after warm up, get a can of cold spray and spritz the transistors for a quick test.
 
2SC1000 are also flagged on the 'noisy' list. These are also found on the Phono as well as P400 Pre and Tone Amp PCB.
 
Do you hear the static on all selector inputs or just some (AM, FM, Phono, Tape, Aux)? Do you hear the static all of the time or only when playing music?
Az @mbz suggests, to isolate the problem to the Preamp or Main Amp, connect a stereo RCA cable to the Preout RCAs to another amplifier and see if you still hear the problem.
Next, connect another Preamp output to the Main Amp RCA inputs and see if the problem persists. This will isolate the problem to a few boards on the 2270.
 
Last edited:
I service vintage audio for a living. I find in basic repairs by troubleshooting down to the defective component(s), I find that semiconductors cause issues at least 10 times as often as capacitors. I do find bad capacitors causing issues sometimes, but I determine transistors to be the culprit much more frequently.

I cringe when I read about someone convinced that recapping their unit will fix it with out doing any troubleshooting. I suspect the possibility of introducing additional issues in to the mix is quite high.
 
Small update: I fed a clean signal from my dac to the main in and the crackle disappeared, which leads me to believe its the preamp and probably the transistors?
Thanks!
 
Yoast said:
Small update: I fed a clean signal from my dac to the main in and the crackle disappeared, which leads me to believe its the preamp and probably the transistors?
Thanks!
Click to expand...
FWIW I always rebuild P400 and P450 entirely, all transistors, all electrolytics, all ceramics. C1000 is in the naughty list.
 
You must log in or register to reply here.
Back
Top Bottom