Hiraga "le monstre"

[Will]

Originally posted by audiomanics
My PCB layout. Single sided, short powerlines, thermal coupled transistors, Faston connectors.
Comments please.

Kees

Originally posted by audiomanics
For the Fet's (2SK170 and 2SJ74):
These are grouped for their Idss: Without: 2,6-20mA
GR = 2,6 - 6,5 mA BL=6,0-12mA and V=10-20mA
Y is probably the same as V
For the normal transistors (2SC1775 and 2SA782):
These are grouped for their hfe: no ext.: 400-1200
E = 400-800 and F= 600-1200

As you have to match the transistors you have to measure the parameters of each transistor individual anyway..

For the fets you can change the resistance of the trimmer to get the correct bias and the current through the endstage.
It has been described somewhere in this tread before..

Kees

Would you be kind enough to offer a kit with the matched transistors (we can get our own resistors and caps) ?
I for one will be interested in 2 stereo pairs of amplifier to power midrange and tweeter.

[audiomanics]

Originally posted by Will

Would you be kind enough to offer a kit with the matched transistors (we can get our own resistors and caps) ?
I for one will be interested in 2 stereo pairs of amplifier to power midrange and tweeter.

Yes, i will be kind enough but unable, at least for another couple of months. Maybe, in the second halve of this year..

Kees

[neazoi]

Do transistors in each single channel need to be matched? since they are different types?

[audiomanics]

For the Fets its mandatory but i do it for all other transistors aswell..

Kees

[neazoi]

And how about carbon composite resistors? would they be better be used in this circuit or not?

[JohanH]

Maybe this will help

http://www.diyaudio.com/forums/showt...769#post437769

Also; there's a thread in the tubes section that deals with CC vs tantalum

Tantalum VS CC & metalfilm

Cheers,
Johan

PS I prefer tantalum (so did Hiraga)

[woody]

Are there any boards available for this amp besides those
from PC Design. I woundn't feal right about buying from them
with there whole line of Pass boards that are not okayed by
Pass.

On another note has anyone used those big 1F or larger
caps intended for car audio with this amp?

[neazoi]

Originally posted by woody
Are there any boards available for this amp besides those
from PC Design. I woundn't feal right about buying from them
with there whole line of Pass boards that are not okayed by
Pass.

On another note has anyone used those big 1F or larger
caps intended for car audio with this amp?

There is a board components layout from a member here. I spent two hours of image editing to make it a clear board free from components (silly a bit, as I could have made one of my own at this time :P), so here they are. Note, I havent checked the layout for errors but it seems simple to check.

[neazoi]

And here the layout.

[audiomanics]

You could also have asked Audiomanics if he wanted to post it..
Sure he would..

I will make an PDF today and post it.. Then it should be accurate in size aswell.
BTW the layout is in mirror.. that's good while transparents should be printed that way..
This print has never been made before, while i'm not able to do that at the moment. So it is never been checked working..
I think it's ok, but if you see an error PLEASE let me know..


Kees