My latest Patek rip-off GC.

[matjans]

hello all,

I've been looking for a place to show off my newest gainclone . Couldn't really find any ongoing threads for it so I thought I'd start a new one. Well, here it is.

A blatant rip-off of a Peter Daniel "Patek" clone (hmm, a rip-off of a clone ).

Anyway, I finally understand what all the fuss about those clones is about; it sounds surprisingly good. After having built a couple of amps for testing purposes I came up with this one. Or actually, I agreed on the opinion of many other people that the following specs are pretty good.

2x Rubycon BG 1000uF 50V
1x rubycon BG 4.7uF bipolar input cap
Riken Ohm for setting gain: 22K/1K
-> I've just ordered some 22K Caddocks
Standard carbon 1W for the rest.

It's been playing for about 8 hours now and already it outperforms my previous GC's.

A few pic's.

(mods: if you guys think this shouldn't be a separate thread move it somewhere else !)

 

[matjans]

2nd pic

.

 

[matjans]

3d picture

The interior: a copper bar (heatsink) and some silver-plated copper wire. Haven't isolated the case yet but there's absolutely NO rf noise. No humming either, it's just dead quiet.

 

[Peter Daniel]

I see, in some ways, you even improved on the original Patek concept. Well done.

From all resistors I tried, Caddocks seem to be the best for feedback loop.

 

[matjans]

thank you peter.
(what ways are you referring to btw?)

well, with this amp being my standard amp for the time being i'm looking for an active pre. Does anyone have any ideas what goes well with a GC? I'm actually looking for a simple tube preamp... No phono stage needed (as i won't be using any vinyl)

sorry analogue fans but those things are way out of my budget for now...

 

[Nuuk]

Hi Matjans, nice little GC there!

As regards a 'simple valve preamp' THIS is what I built earlier this year based on suggestions to a similar request.

I'm still working on it (mainly hum issue now, I may have to go to DC for the heaters) but it does sound good!) BTW - I used the Stephen Robinson circuit.

 

[ronc]

Good job!
All mine look like black boxes?
Have you tried battery P/S? Try it , the results will surprise you.
ron

 

[matjans]

thanks nuuk, i was thinking about something like this . most of the site is in dutch though so here's another link (schematics) .

Triodedick has a *lot* of tube amps on his site -hence the name- (some stories are in english) including some very nice 300B's (and a 211 whoo!!).

ron: haven't tried it yet, maybe i'll rip the battery out of my car (and my dad's car.... and my mom's car...)

 

[Peter Daniel]

(what ways are you referring to btw?)

Nicer wood panels and more pleasing proportions

I see you still use regular bridges. Try MUR 860.

Also, the footing on the amp is quite critical. Try to use one foot on each site, and then a spike (at one point only) under the central copper bar.

 

[matjans]

hi peter.

in my previous amps I used onsemi mur840's and mbr840's. Can't really decide which i like best. the regular bridged sound a little soft (which is nice), the mur840's sound a little harsh (which is nice when playing rock music) and the mbr840s sound somewhere in between the previous two. Which is nice aswell.

dilemma

I don' really know what's going on btw but sound sound quality is varying with the hour. Bass was sloppy all of a sudden and now it's tight as hell. blackgates burning in ??

 

[Peter Daniel]

Yes, BG need to be broken in. I don't switch off my amps at all.

 

[Upupa Epops]

Caddock

To Peter Daniel : Which type ? Caddock have many types and also others manufacturers have similar. P. S. : If you hear differenes between rectifiers in PS, your amp is not OK ( rails and ground lines ) .

 

[Peter Daniel]

I only tried MK132 as it's most popular and right sized (for feedback loop) Caddock resistor.

If the amp's not OK, it's not rails and ground lines fault, but National's design team

 

[Upupa Epops]

To Peter : I am assuming, that National team don't drive your brain and hands by making your own PCB , isn't true ?

 

[Peter Daniel]

Who mentioned PCBs?

I don't remember when was a last time I used a PCB in an amp.

 

[Upupa Epops]

No PCB

Was you born in year 1910 ? When I look on your photo, I mean that you are younger . Also without PCB your wiring is not OK . Imagine : NASA makes "high tech " product such as Space Schuttle and brag about that is made only with solderind iron .

 

[Peter Daniel]

Well, this amp is not a space shuttle and since only 3 parts are required, it would be extremally stupid to use PCB.

I bet you can't do this type of assembly with a PCB: http://www.diyaudio.com/forums/showthread.php?s=&threadid=22733&highlight=

And 2 dimentional plane here would actually introduce more complications than improvement. Are you gonna argue that wiring is not OK here as well? Because I don't see any wiring.

 

[Upupa Epops]

PCB or not PCB

Minimal count of devices around typical integrated power amp is approximately eight, not three. Pics which you show me, I take as good for prototype, not as like final work - if is it enought good for you, my professional honesty say no. In this case we are probably quite different - I mean, that DIY may be made the same as the best profi product and man should not to say "..it play, let it be..." .

 

[Peter Daniel]

Re: PCB or not PCB

my professional honesty say no

..and let's end it up this way.

PS: For you it may be just professionlism and good looks that count, for me it's a bit more than just that. Check my signature, to see what I mean

 

[matjans]

so what;s up with threadjacking these days anyway? mods: be more strict ??