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I usually work on tube equipment, so I may need a little push to resolve the issue I'm having with a Marantz 2230.
I hope I'm posting in the correct section. Thanks for reading.
I'm just looking for a place to start. If I was working on a tube amp, I'd probably look into the signal capacitors.
The problem seems simple. Here is the symptom:
- When powered on, the receiver plays fine through both channels.
- After roughly 10 minutes of operation, the left channel makes a brief hissing sound and fades completely out.
- If I power the receiver off and turn it back on, the left channel plays again immediately but dies off, justas mentioned previously, after 30 seconds to 1 minute of use.
This happens regardless of what input source I'm using. I have isolated the issue to the receiver itself. The issue occurs very reliably.
Thank you very much for reading my post.
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
output caps.
There are 3 larger caps in the 2230.
Biggest is for power supply.
The other two are for the output to speaker terminals.
Sounds like one of the output caps won't hold it's charge.
Easy to replace all three cause they are accessible.
I had experience in replacing bad output speaker coupling capacitor, first symptom will be the loss of the low frequency response due to the reduction in value of the capacitor because of aging and dry out problems.
I would still say the problem is in the preamp section from what I had suggested by reversing the left and right signals, and the problem moved from left to the right channel.
. . . be careful and prepared to spend a little.
The big Elnas in the coupling positions are difficult to source, and greatly influence the sonic signature. The originals are very nice sounding. Not sure where the OP would want to take this to get a good match. Black Gates? Those are large dollars.
Still, I'm skeptical that an output coupling cap would cause this problem. A bad cap won't usually give you a clean first 30 minutes over and over. It's got all the earmarks of a thermal. But, I've been proven wrong before.
As budm suggested, I switched pre/power jumpers and the symptom did switch channels.
However --
The guy who owned this before me must have been a shut-in who smoked 2-3 packs a day. The pre/power jumpers were covered in thick tar. I removed them and cleaned them thoroughly. I also took the time to (re) clean all pots and switches, just to be sure.
The problem seemed to correct itself at first -- I listened to music for an hour without incident, then it started again, same as before. The left channel hisses in a fading manner for about 2 seconds, then goes out completely.
Thanks for your time.
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
i would leave it hook as I suggested, if the problem comes back and it on the right channel instead of the left channel, then it will be for sure is in the preamp left channel.
I had the exact same symptom with an early Marantz receiver. Turned out is was the relay. My tech cleaned it and it has worked perfect ever since. Good luck, hope it's a cheap fix but the 2230 would be worth putting some money into if you had to IMO.
Thanks for the reply. Do you know where this relay is located or with what stage it's associated?
Thanks,
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
The relay for the Marantz 2245 and 2270 is on the power supply regulation board. Apparently the 2230 doesn't have the relay, from what I can see on the schematic.
I'd try replacing the caps on the power supply P800 and the preamp P400 boards if it were me. I've had good luck with Panasonic FM and FC caps from Digikey.
Good luck with it.
Sorry, I don't. It's a different receiver so it would probably be in a different place anyway.
Your problem sounds thermal from the timings described.
If you narrow it into the amp section, take a look at the heat sinks to make sure the bond to the outputs hasn't dried out. If so, the outputs may be overheating.
These are capacitive-coupled designs, but the main coupling Elnas are pretty durable. I wound up recapping the output boards on mine to correct a frequency imbalance, which made a world of difference. Total cost was about $7.
I'm guessing your problem to be thermally related, however. A can of component cooler may be your best friend here.
What brand of caps did you use? 716P might be a worthy/cost effective contender if they're close enough in composition to the originals.
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
On the output boards, you're not recapping films, but small radial electrolytics. I used higher grade Nichicons, which were still inexpensive.
Unless there is a problem with them, I'd leave the big Elnas alone.
You should also need to remove these old glue on the PCB.
If you Google 'conductive brwon glue' you will see what kind of problem it will cause.
http://www.siber-sonic.com/audio/carnage.html
httpwww.tmworld.comarticleCA6623639.html
httpwww.tmworld.comarticleCA6632290.html
...
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
which they do...then external jumpers may solve the problem completely.
To which jumpers are you referring?
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
Just get a set of RCA cable, take the output of the LEFT pre-out and connect it to Right Power amp input, take the Right pre-out and connect it to Left Power-amp input. If the problem moves from left to right channel, then it is in the pre-amp, if the problem stays in the same left channel, then it is the power amp section problem.
Excellent suggestion!
It is all about common sense and logical thinking.
Does this receiver have a set of pre-out/power-in jacks on the back? If so, further narrow it down to the preamp or power amp section.
While you're at it, confirm that the power supply voltages are ok. I assume you have a schematic, right?
Cheers,
David
Yes, it has pre-out/amp-in jacks. I haven't tried using them individually, but --- the symptom also occurs when using headphones through the front panel 'phones jack. I would normally assume that this indicates that the issue lies with the preamp section, but I could be wrong.I just tracked down a set of schematics, which is linked below. They aren't very clear. I'll continue looking for a better copy.
Adam
I'm not an audiophile. I'm a sound junkie, a music lover and a tinkerer - but definitely not an audiophile.
Edits: 06/02/09
The schematics indicate that the headphone jack is tapped off the speaker-out jacks, so using headphones won't tell you whether the problem is in the preamp or power amp section.
As doodlebug suggested, if you've got a seperate power amp, hook it up to the pre-out jacks on the back of the 2230 and see if the problem continues.
Post your results. Good luck.
If you have some tube gear try patching out either the preamp section or the amp section.
At least it will give us a place to start.
Sounds like a cap going south.
charles
I believe I worked on the same model receiver last year and found a couple of the small electrolytics (one at the top of each of the vertical circuit boards) had gone south and if you were to put a little bit of pressure on the side of the cap, then the lead would pull right out of the lytic's bottom. Maybe you could check over all the electrolytics with some magnification and see if you can spot a bad one. The two I replaced looked as if there was gray mold seeping from the bottom of the cap where the lead comes out. I put in some Nichicon KZs of higher voltage for replacements and then sent it to my father-in-law with a set of refurbed Advents. He is a happy camper.....
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