Pavel Dudek's (Upupa Epops) amplifiers

[PMA]

Upupa Epops has been displaying his opinion to some amps for some time here. He had been criticized that he did not show his own. Now an interesting discussion has started at http://www.diyaudio.com/forums/showt...991#post330991 regarding Steven's design, a bit similar to Pavel Dudek's ones. Pavel Dudek decided to release two of his amps developed in 1992. Here they are:

http://web.telecom.cz/macura/dpa_386.pdf (mosfet)
http://web.telecom.cz/macura/dpa_222.pdf (bipolar)

with PCB's as well. The amps serve as reference power amps in our country, compared with most of the well known amps and beating them in clarity, purity and resolution. Some minor improvements have been recently made in the input stages, not shown at linked schematics.

[Peter Daniel]

And for anybody to whom his moniker might not be completely clear, this is what Upupa Epops is, and I believe this is what his last name means in his country. I hope he doesn't mind my explanation. Smart choice, BTW

[PMA]

Exactly, Peter .

[MikeW]

Very nice looking amps. Don't you like power resistors?

[Upupa Epops]

Parallel connection of small resistors ( 0207 ) have several advantages against bigger ones : they are problemloss to buy, summary price ( per wattage ) is lowest, have standardly 1 % tolerance, thanks parallel connection is reliability very good and, what is for me very important, PCB looks nice .

[Jan Dupont]

I have seen these layouts before, and I must admit that I'm very fond of the beautiful and compressed layout

[jcx]

i would give the layout a "fair" rating, i seldom find that all my 2 legged critters just happen to want to be scrunched up together shoulder-to shoulder in parallel rows for best electrical performance but the lack of squirrelly tracks snaking between and around parts does show the care put into parts placement - the layout may get better than fair marks for ease of assembly

and as always power/signal ground and supply rail routing can really only be evaluated and perfected within the context of the whole chassis and power/signal i/o connections

[Upupa Epops]

for your nice words . Outside of this PCB are only toroid, input connector, protection circuit and output binding posts. True this extremly short rail ways have amp very good SNR ( more than 122 dB, refered to full output, IHF - A, or 117 dB linear).

[cough]

Just adding here picture of Upupa Epops DPA386 amplifier.

[DarkOne]

Hello,
I see that Pavel Dudek's amplifiers are still better, I remember that few years ago magazine called "Amaterske Radio" had few of them on theis pages.
But I don't like one thing, overall negative feedback (I'm one of guys that don't like overall negative feedback).


Tak nech vam to pekne hraje aj s tou spetnou vazbou.