Kenwood 500 Restore Help Needed

[dj7675]

I am picking up a Kenwood 500 and am wanting it restored. I read this fantastic thread about @hopjohn thread:
http://audiokarma.org/forums/index.php?threads/set-to-restore-a-kenwood-model-500.711239/

I wish I had the skills to do this, but I definitely do not. So the next best thing would be to locate someone locally to me (Oregon Coast) to do the restore. I have located a guy and he has provided me a quote to do the following work:
1. Replace all of the electrolytic capacitors
2. Replace any transistors that are needed ( with exception of the power transistors, they rarely fail and the one’s on this amp are quite good )
3. Adjust the bias and balance
4. Clean all switches and pots
5. Clean the PCB boards
6. Clean the interior as needed
7. Any other minor repairs needed will be done during inspection

My question would be, how complete is this list to getting it restored like the thread above? What should be added if anything to the list in order to get it completely restored. I really want to keep the unit a long time and want it to sound as good as possible.

Any help would be greatly appreciated.

Darin

 

[gort69]

I did my own 600 and followed John's fabulous thread step by step and part by part. It is a very time consuming (the pre-amp board is a special challenge) and rewarding process, and in my non-expert opinion a very comprehensive rebuild. Smarter folks than me might have more to add, such as replacing the three metal can transistors on each amp board even though they are working. Since it's that far apart a new power switch makes sense - it's available and inexpensive

 

[dj7675]

Thanks for the

I did my own 600 and followed John's fabulous thread step by step and part by part. It is a very time consuming (the pre-amp board is a special challenge) and rewarding process, and in my non-expert opinion a very comprehensive rebuild. Smarter folks than me might have more to add, such as replacing the three metal can transistors on each amp board even though they are working. Since it's that far apart a new power switch makes sense - it's available and inexpensive

Thanks for your input. So you would possibly add

-Replacing three metal can transistors on each amp board
-New power switch
-Rebuild the preamp board?

Any other ideas to add to the list for him to make sure gets done?

 

[gort69]

All of what I mentioned are taken care of if he follows John's to-do list. I don't recall replacing anything other than electrolytics on the pre-amp board - just doing those was challenge enough.

 

[dj7675]

I referred the tech the pdf and sent him an emailed him a link to that thread. That should be enough to spell out exactly what I want, correct?

 

[gort69]

I wiil say YES - hopefully John or EchoWars will check in (they're way smarter than me!). The more I play this amp the more I like it!

 

[hopjohn]

The restore pdf is pretty comprehensive. Any list should include a new power switch / new safety caps. The restorer will benefit greatly from the list where the pre-amp is concerned because it is not well (not at all) documented by the service manual. I might also emphasize going to film caps where appropriate with anything 4.7uf and under since this amp is worthy of that expense. These aren't the easiest things to work on so you'll want someone with years of experience in vintage gear. It's a special piece of kit and it should be in the right hands so don't be shy in asking questions or making reasonable demands.

 

[dj7675]

Appreciate those taking the time. I really want it done right to get the most out of it. In addition to the list I posted in the first post... if I added the following would it be enough ?
-go to film caps on anything 4.7uf and under
-new power switch/new safety caps

If I go either his list and add those two things will that address enough to get it "restored"? Or are there any other major components to make sure are replaced?
Again, appreciate the help.

 

[gort69]

I would go with John's list if you can do so without making your tech angry. Some old pros can be pretty cranky, and justifiably so if some whippersnapper tells them how to do their work. Not saying that your guy is cranky or that you're a whippersnapper, but you get the idea. If I thought he was agreeable, I'd offer to buy the parts myself and bring them to him in bags that were labeled with a Sharpie as to exactly where they go. That list John made is awesome - it is complete, accurate and makes ordering a snap with a link for each part. All you have to do is click on the link, check to see that it's in stock in sufficient quantity, enter the quantity and add it to your cart - then move on to the next part..

 

[dj7675]

I would go with John's list if you can do so without making your tech angry. Some old pros can be pretty cranky, and justifiably so if some whippersnapper tells them how to do their work. Not saying that your guy is cranky or that you're a whippersnapper, but you get the idea. If I thought he was agreeable, I'd offer to buy the parts myself and bring them to him in bags that were labeled with a Sharpie as to exactly where they go. That list John made is awesome - it is complete, accurate and makes ordering a snap with a link for each part. All you have to do is click on the link, check to see that it's in stock in sufficient quantity, enter the quantity and add it to your cart - then move on to the next part..

That would be my first choice as well. I don't think my local tech is willing to do the list in John's list... 30 years experience, etc... It isn't his way of doing things. Seems like he likes to replace what is necessary. So I am a bit stuck on wanting to do a fuller restore as in John's complete list, and locating a tech that would be willing to do it. Anyone know of a good tech who would be willing to do something like this?
... Not as much of a whippersnapper as I used to be (40+) but don't know anything compared to theses guys that actually do the work! But I do want it restored as good or better than when it was original...

 

[hopjohn]

Repair techs only repair an immediate problem. Restorers provide you 30 years on of audio bliss. Be prepared to pay for it and for it to take some time to find their loving hands.

 

[dj7675]

Well, my Kenwood 500 will be arriving today but my local guy changed his mind. So now I am still stuck without anyone to restore/recap it. I checked with 2 places in Portland and all of them said they just do repair. Rolland Barr from Carver Audio Repair said he could do it but is 3-4 months out (which might be my best/only option). Anyone else have any recommendations? Shipping is fine, I just want it done right as I plan on keeping it a long time.

 

[jalexmichael]

Dj7675, I also have a 500 and would love to get it restored.

I'm also in Portland, OR area. Did you ever find a local-ish tech to do work on your Kenwood?

-Thanks for any info,
Jacob

 

[Gamsma]

Dj7675. I am also in the Portland area and have a 500 and a 600 I am thinking about having restored.

Any tech suggestions would be welcome.

Geoff