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Kondo Ongaku needing advise

Need advise from members. 

This is my Kondo ongaku amp. I bought it brand new from a US dealer in 2008. I started notice some discolouration 2-3 years ago on the copper chassis. It is getting worse. It likes kind of rusting but it is NOT on the surface. It is growing from the inside of the chassis. If you feel the surface of the chassis by hand you cannot feel it and the surface is smooth. The local dealer inspected the amp and found nothing wrong except the chassis. All other plates are in mint condition as I really take good care of it. I emailed Kondo Japan company and they asked me to ship it back to the company for repair/ replacement. I live in Asia and, even do, the company quoted me USD 6500 for replace of that chassis. Anyone has a better idea of what it is and how to treat? It’s a bit too expensive to replace one chassis at the cost of USD 6500.


nicksun
12 responses Add your response
gsm18439
895 posts
 
Can you upload some photos?
roberjerman
4,319 posts
 
Typical copper corrosion! Regular polishing with Copper Brite will keep it at bay!  The only permanent fix is application of a clear sealent (laquer or polyurethane) over the copper. Be thankful it is only on the inside! It will NOT affect the sound quality! 
roberjerman
4,319 posts
 
Silver does the same thing - it turns black! Copper turns green/blue when exposed to air (oxidation - rust). A clear sealant applied before this happens is the solution. I thought that the Ongaku's outer surfaces had this already done? Apparently the inside was neglected! Rather unacceptable in a $40K+ amp!
testpilot
922 posts
 
Did you ask Kondo if the copper top plate is raw copper or copper with a clear coating?  If the former, you can expect copper to oxidize.  If clear coated (which protects copper from oxidizing), I would ask Kondo why the top plate is now oxidizing?  Perhaps a manufacturing defect?
testpilot
922 posts
 
If the oxidation is merely on the inside of the amp i.e. not seen,  I wouldn't be too concerned.  My understanding is that copper was used for it's EMI/RFI shielding properties. 
rsf507
2,310 posts
 
Nice amp but way to euphoric IMO. Have heard it at least 6-8 times over the years and just couldn’t warm up to it, nor could ever afford one. 
Sorry to hear of your issue, seems 6500 is way to expensive nor worth the expense of shipping back and forth to Japan. If sonics are not affected just enjoy.
twoleftears's avatar
twoleftears
5,318 posts
 
Gotta say that euphonic amps make me euphoric.
jond's avatar
jond
5,776 posts
 
Owning a Kondo Ongaku would make me euphoric indeed.
mickeyb
570 posts
 
Clean with brasso and apply a clear lacquer. It will take time but not 6500 usd of your time. I did this to an old Sherwood and it turned out beautifully. That’s a great piece and worth the elbow grease. 
sdj888
13 posts
 
Also you can clean with Silvo, it's apparently finer than Brasso, maybe finish with Silvo, just a thought. 
karl77
2 posts
 
If you clean it with Brasso Silvo or other stuff the best it is to finish it with Cape Cod polisher and you can not apply poly or other sealer you have to clean it with gunk or alcool 90% to remove all grease and product thing before put poly or métal lacquer if not it will peel of ....I am french excuse my English 
astolfor's avatar
astolfor
317 posts
 

Solid copper… it is a piece of art, both sonically and construction.

my 1990 is in perfect condition, it gets polished with a copper polisher and protector.

Get it repaired, $6500 maintenance for a $100k amp is nothing.

 

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