Concorde/K60 Capacitor Questions

[lgehrig4]

I'm building a KF50/60 hybrid. The main board is basically K60 and the power section & OT are KF50.

On the power board there should be two 8uf 250V caps and I purchased 150V by mistake. Can I use these or should I get 250V?

Next question is that I still have to purchase the 80uf caps that go under the board. I believe Komet uses Sprague. How do the Illinois brand compare? I was going to purchase some other stuff from a site that only has this brand in that rating.

[Synchu]

I used 150v rated 8uF Sprague ATOM caps. No problems whatsoever, bias tap on my PT is 75v and if yours is not more than 150V then it shouldn't be a problem as well.
I used Ilinois caps too. The amp sounds good(amazing to my ears) but then I didn't try it with Mallories for filtering in order to compare.
Niki

[M Fowler]

My first K60 was a clone so was as close to Komet original as possible.

My second K60 was built in a Bassman size chassis and my board designs with Illinois caps. Sonically I can't hear a difference.

[lgehrig4]

Thanks guys! I figured it wouldn't make much of a difference in that part of the circuit, but you never know with sensitive amps like this.

I don't know much about diodes other than how to orient them on the board. I have some small ones that I used with my Express and I found that I also have about 12 larger ones. Are the differences basically power handling or do they have different values like caps/resistors? I'd like to use the large ones, at least on the small board that replaces the tube rectifier.

The codes on the large ones are IN5408 and below that AC31
The codes on the small ones are IN4007 and MCC 6

Nice looking amp by the way!

[M Fowler]

IN5408 handle 600v

IN4007 handle 1000v

[lgehrig4]

Wow, so the little ones actually handle more voltage? Surprised about that

[Synchu]

5408 actually handle 1000v, but are rated for 3A, while 4007 are 1A.
Niki

[lgehrig4]

So could I use either in the Concorde? I'm actually sitting in front of my computer soldering the board now.

[Synchu]

Yes. You could use either.
Niki

[lgehrig4]

Almost finished with the boards. Just waiting for 80uf caps for the bottom of the board.

[IMG:800:600]http://i43.photobucket.com/albums/e390/lgehrig4/P1040268_zps2b646964.jpg[/img]

[IMG:800:600]http://i43.photobucket.com/albums/e390/lgehrig4/P1040266_zpsdfc9ac1c.jpg[/img]