Another Harman Kardon A500

[WXM88]

Went to a guy's place to look up a Luxman amp. As our conversion about the amp went, he mentioned that he also has a Harman Kardon A500 for sale. 10 minutes later I had an HK amp in my trunk. On my way home, I could not help thinking that was really a risky move as I just dropped a few hundreds dollars without even listening to it...

Got home, hooked everything together and tried it with a pair of JBL 4410. I was so happy, the amp works great, sounds warm and sings beautifully. I was pleasantly surprised that the 4410’s mate so well with the HK A-500. I have the 4410 side by side with a pair of JBL L96, always feel they are kind of harsh comparing to the L96. The HK definitely smooth them out.

I am thinking maybe I shall do some refresh on cosmetic details. Anyone suggestion on
(1) Refresh the wood veneer?
(2) Polish the ugly knobs?

 

[WXM88]

Here are some pictures...

 

[WXM88]

Better iPhone pictures:

 

[Greg Nal]

Looks better than the one I just got...We'll have to see how she cleans up...

 

[Patrice B]

Great amp once restored... Mine is in the living room with two bookshelf speakers, a Dynaco FM-3 and a Dual 1019.

The bulb in your power switch appears to be dead BTW.

Lucky you, the case is beautiful.

 

[FlaCharlie]

I am thinking maybe I shall do some refresh on cosmetic details. Anyone suggestion on
(1) Refresh the wood veneer?
(2) Polish the ugly knobs?

That looks to be in really nice shape. Nothing wrong with a good cleanup but I'd be more concerned about its electrical condition.

Has it been properly restored? Perhaps you could post some pics of the internals.

 

[WXM88]

The internal all appears to be original. I know it is probably a good practice to recap everything, but since I would be repairing them myself, I usually just deal with them when there are problems. I currently have its big brother - a HK F-500x tuner on my work bench. That is actually the whole another struggle. (https://audiokarma.org/forums/index.php?threads/harman-kardon-f-500x.942736/). Will take some pictures when I get the A500 on the bench.

 

[WXM88]

The bulb in your power switch appears to be dead BTW.
View attachment 2081755

@Patrice B You are right, I just checked and the light behind the switch is off. Any idea where I can get a replacement?

 

[WXM88]

OK, Put the A500 on the bench now next to its big brother F500A tuner. The electronic looks original. Here are a few pictures:

 

[WXM88]

While I was there, I also took out the front panel and remove the burnout bulb. It is #1847, pretty east to find. Just order a few LED version of the lamp from Amazon. We will see.

 

[Patrice B]

@Patrice B You are right, I just checked and the light behind the switch is off. Any idea where I can get a replacement?

I guess it’s only a #47 bulb but I will verify on the schematic...

**Oops, too late!

 

[Patrice B]

I guess it’s only a #47 bulb but I will verify on the schematic...

OK, Put the A500 on the bench now next to its big brother F500A tuner. The electronic looks original. Here are a few pictures:
View attachment 2082523 View attachment 2082524 View attachment 2082525 View attachment 2082526 View attachment 2082527

Yes, completely stock. I hope your 7355´s tests good.

 

[Patrice B]

One DC balance pot looks to be a replacement. Mine were not measuring good so I’ve put some multiturns in place.

 

[WXM88]

While it is on the bench, I replaced the four50uf 6v capacitors. They were totally out of the spec, one of the even showed ‘0L’ on my esr meter. Also replaced the #1847 bulb with an LED bulb. It lights a bit blue’ish, but I will live with it.

 

[buickguy62]

You might get a violet LED.
Here's a pack of 10 for about $5 + shipping. They are bright, to me perfect for the button. Also, often the button fades over the years, you can 'restore' it with some translucent paint, be careful, only needs a very light coat and mask off the shoulder area of the button.

https://www.ebay.com/itm/10-Pack-6-...324715?hash=item3d1e2dd32b:g:89cAAOSwmtJXcCoe

 

[Patrick_W]

Also, often the button fades over the years, you can 'restore' it with some translucent paint, be careful, only needs a very light coat and mask off the shoulder area of the button.

Thanks for the tip on restoring the button color! I have an A500 and I kept trying to paint the bulb. My memory from when I first obtained it 10 years ago that it was the bulb that was painted not the button. But as the color faded over the years I could not tell what was purple. Is there a source for the cardboard tubes that help focus the light?

 

[buickguy62]

I think the cardboard tube is not to focus the light but to keep the light from showing out from the bottom of the faceplate. I'm not aware of any source for the tubes, but a piece of electrical tape over the slit works well for either the lamp or the LED.

 

[WXM88]

Thanks for the tip on restoring the button color! I have an A500 and I kept trying to paint the bulb. My memory from when I first obtained it 10 years ago that it was the bulb that was painted not the button. But as the color faded over the years I could not tell what was purple. Is there a source for the cardboard tubes that help focus the light?

Not sure my broken one was original, but it was not painted. When I got my LED replacement at Amazon, I do have options for different color, but I got the white one, guess I could have chosen a warmer color. Anyhow, I did not bother me too much. As I got 10 of them, white might be easier to apply on other application.

 

[Patrick_W]

a piece of electrical tape over the slit works well for either the lamp or the LED.

That is a good solution! Thanks for the tip. My cardboard tube is ok, but it is disintegrating. It probably cannot take another light change.