So to get things started off on a round 2 GB:
- Iancortez 2 PCBs
- Jacques Antoine 2 PCBs
- Zman01 (TBC) 2 PCBs
So if we can get 2 more people we can do another one to get 10 minimum. I will probably wait for at least 7 people total though to make it more efficient.
If you are interested please edit this list and repost it.
Last edited:
Looks really good Marc. It's no surprise all your parts fit the designated locations perfectly. What kind of caps are you using as 10uF film? I wonder if I can improve SQ with switch from ceramic to film at that location?
I'm getting a little concerned the remainder GB boards still have not arrived yet. Please let me know of you have any news.
Hi X,
no i haven't enough time. I must first match 2 couple BC556B/546B. KSA/KSC and IRFP are allready.
Marc
no i haven't enough time. I must first match 2 couple BC556B/546B. KSA/KSC and IRFP are allready.
Marc
How is the build coming along? First sound yet?
That's a nice looking (and sounding) combo!
That is a very nice set!!!🙂
I don't think you need to match KSA and KSC as offset pot handles that. Vgs on same sex IRFPs should be matched to keep currents through source resistors more balanced, but no need to match Vgs of both sex to each other as offset pot handles that as well. I agree matching BCs is good as that lowers distortion and allows excellent thermal tracking.
My DC offset is stable within 1mV once warmed up.
HI
Sorry not much, I think I will go for the higher power version. I do have enough parts for that. I did some work on the layout just I need to etch some PC boards for these and other amps.
I will use your boards for tests it looks like compatible with my Darlington version.
I can not work fast for the actual reason I stated before. I will have to have a trip to Staples to do some laser printing for the boards. I want to use JUMA s PS.
Hardly wait someone compare the simple version with the complex one (the one use more caps)
xrk97 I will send you a schematics if you can send me your e-mail address, it is a highly rated a........p
To Marc:
I hope you still have some of the other HexFet explendit design so you will be able to compare the two
Hi xrk971,
-Chris
Why then, would you ignore taking this step? It seems to me that any means of reducing distortion should be taken. That is one major difference between buying an amplifier and building one.
-Chris
I can only find KSC1381E and KSC3503D with 2x hFE ratio or more.
As far as I know, KSC3503E is no longer produced.
May I ask where you purchased both in E grade?
Thnks,
Jacques
I think you misunderstood. I did not say ignore this step. I say this is the one that should be matched.
I am away on travel so cannot look st my amp to verify. You may be right, one is E grade and one D grade. Hfe was in 200 range for both as I recall. Let me check when I get back.