Why re-cap? Once and For All.
After watching the debate go on for years, wondering myself at first, reading threads where the Master's came to believe, finding documents from the cap manufacturers, doing many re-caps and experiencing the results and finding issues while re-capping, I'd like to post a thread that becomes the "link to" once and for all.
Subject: Marantz 2015.
Condition as found, working for the most part but FM on the tuner had an issue.
I found a transistor on the tuner with rotted legs, repaired that and FM works fine.
Unit is in good cosmetic condition and I set it aside to do a restore and flip for profit.
I just went through the unit and found 4 electrolytic capacitors with obvious problems.
After the re-cap, one channel was weak and lousy.
I could see that someone had been hacking around in there, the solder jobs were obvious and a wire had been cut and re-attached different than factory.
I FINALLY found that a capacitor had been added to the trace side of the tone board, similar to a factory mod, that was the problem.
The bad caps I found were in the power supply and on the main amp.
I am surprised it worked as well as it did.
Well, NOW it works.
Since the manufacturers flat out say electrolytic caps have a shelf life. They explain why the deteriorate (dry out). I've seen enough problems directly related to electrolytic caps on "working" gear to know, you cannot trust them.
The argument "if it works, don't fix it" is wrong. It may "work", but its not right.
Here are the caps I found in a "working" unit.
FWIW, I have found "rotted" caps like this in Marantz gear before. Most of the gear "worked" some had issues but the only way I found most of the bad caps was during a full re-cap. Once unit I accidently found it by pushing the cap up right and it seemed too loose. Just dumb luck on that one.
Here is what hides in "working" units.
Re-capping is a lot of work.
It's worth it on anything you like.
It's in the multiple $100 because of the labor and skill.
And, I've done many tuners and they all work better. I do not have the tools or skill to re-align.
I have seen $600 tuner bills and not one damn electrolytic cap was replaced, so I really have my doubts about THAT!
Now, I need to go listen to a nice fresh restored Marantz.
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