A semi idiot updates his dream amp; KA-8100

I’ll bear that in mind. I’ve ordered the wire and wrapping tool for the moment and hopefully that will allow me to do it properly. Won’t look identical but will look a lot better than having a repair in an otherwise spotless amp.
 
I’m also thinking about how to treat the main filter caps. I want a stock look and so have 2 options I can think of.

1. Use the original caps as a cover for the new ones
2. Create a standoff for the new ones so I can elevate them

I’m thinking option 2 as it will ensure the caps are in the open (not sure if caps get hot), plus I also get the look of the new caps. I was thinking of doing this by turning some PVC on my lathe and create a ring for each cap to sit on (heatshrink the cap to this ring) which I can then stick down temporarily to the board, before the clamp goes back on.

This leaves the question of how to wire in the caps. For that I was going to take off the tabs off the old caps and jumper them to the cap with the lead wire or some extra wire as required. Will this work?

I get the standard cap height, clamp looks normal, use the standard solder tabs (no drilling the board). I read a webpage about this exact mod but cannot for the life of me find it again.
 
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I’m also thinking about how to treat the main filter caps. I want a stock look and so have 2 options I can think of.

1. Use the original caps as a cover for the new ones
2. Create a standoff for the new ones so I can elevate them

I’m thinking option 2 as it will ensure the caps are in the open (not sure if caps get hot), plus I also get the look of the new caps. I was thinking of doing this by turning some PVC on my lathe and create a ring for each cap to sit on (heatshrink the cap to this ring) which I can then stick down temporarily to the board, before the clamp goes back on.

This leaves the question of how to wire in the caps. For that I was going to take off the tabs off the old caps and jumper them to the cap with the lead wire or some extra wire as required. Will this work?

I get the standard cap height, clamp looks normal, use the standard solder tabs (no drilling the board). I read a webpage about this exact mod but cannot for the life of me find it again.

Jeez !! I guess I`m out of the current BS loop !!
Is this a "Investment Receiver, ect." !!
I personally, while like, and can appreciate the visuals(up skirt as a seasoned tech of well over 40 years) I quit wasting my efforts on minor visuals, like well over 25 years ago !! As long as it`s spec and delivers it performance..
But to each their own !!
I have nice looking gear/setup..
But I listen to it`s sonic delivery, not what it looks like under the hood !!(no staring at the gear whist listening, but in fact the music, you know the reason for the effort, I guess !!

Chase what ever questionable pride that make`s you happy !!
Mercy Sakes alive folks as you see fit !!
 
Yep! I was back on there but thought it was the 8100 post. Obviously not.

Thanks for that.

I assume the longer leads on the caps wouldn’t represent an issue sonically?
 
First mod complete. As I mentioned before one of the speaker posts was stripped. Not a problem as my KA-7100 was exactly the same, so I set about employing the same fix again.

Last time I used a cutoff wheel to remove the posts, but this time I decided to grab the post with pliars and unwind them. Worked a treat and the damage to the threads wasn’t a problem as I had to tap new ones out to M4 anyway.

I’m tempted to test it with my speakers :) but I think I’ll wait until I’ve recapped it as I don’t need the risk, plus I can’t be arsed pulling the old amp out yet to only put it all back in again.

BCB38836-49A5-48C3-8606-C1AC7D949CFC.jpeg
 
@gort69 what are the clear things that look like caps? Are they standard caps? I have my order coming from Mouser and didn’t notice any bi-polar caps like I had in my 7100.

Just want to make sure I have time to make any changes if required or maybe I’m worrying about nothing. Don’t have the amp near me and was thinking about it in the airport.
 
Clear thing? Fuses? They are upright, so maybe that's what you saw. The new relay has a clear cover....
 
That's probably it - there are a couple of them on the control amp board. I left them alone.
 
All I can say is you are lucky your house had a decent breaker and an ELCB. Very lucky.

Tell me you replaced the blue wire with at least 0.75mm stranded mains rated copper. It's a safety issue. Remember, we have potentials of +/-340V in Australia.

It looks like they are the various primary tappings as it is a universal model. All un-insulated too. Awesome safety Kenwood. :(

Consider that one primary wire, tie point or blob of solder can render the entire chassis live and you needing CPR or worse. You dodged a bullet and need to go buy a lottery ticket.
 
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Polystyrene capacitors

Not an issue to leave in then I imagine.

All I can say is you are lucky your house had a decent breaker and an ELCB. Very lucky.

Tell me you replaced the blue wire with at least 0.75mm stranded mains rated copper. It's a safety issue. Remember, we have potentials of +/-340V in Australia.

Agreed. Luckily the connection to earth without power was enough alone to trip the switch, however with power on it would have flipped immediately too. Stupid me for pinching the wire.

Ive ordered new 20 gauge wire and will replace the entire piece and wrapping it to the post as per the factory (or as close as tools will allow). Not powering the unit up until that’s been fixed and the main power board has been recapped except for the bias and centre voltages that I’ve already done (broken wire was covered with tape).
 
...Ive ordered new 20 gauge wire and will replace the entire piece and wrapping it to the post as per the factory (or as close as tools will allow)...

The factory wire wraps use copper wire that is silver plated. If you are able to source this wire, please share.

If you are using plain copper wire, you will not achieve a “factory” connection with wrapping alone. I leave it to you to further research these mechanically cold welded joints.

This is my KA-9100 currently open. I’ve scrapped a small area of plating off the wire to reveal the copper core. Also you can see the copper on the trimmed end.

33B8EC09-AF0C-4FD0-BCF8-912158440718.jpeg

If I were replacing any wire wrap with plain copper wire, I’d be soldering over the wrap.
 
I ordered tinned copper wire. I’ll do some testing to see how it pans out and look to solder if required.
 
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