I don't know, only reporting about early users. Its a good sign it seems also acceptable by a couple of audiophiles but non diyers. There is no pride of assembly element involved. But its still highly subjective anecdotal info. I just hope it will be adequate for most diyers.Wow, sounds like you've created a winner here! Congratulations
Boring meassurement's
Hello here
so, here is some meassurements.
First DCoffset... please look at secund and third picture. As can be seen level is very low, even at startup. Around 4 seconds for stable DCoffset.
Bias level is checked last, very stable as can seen (Stuborn mule grade bias) as Salas would have called it.
My bias is a bit deviated as can be seen, this is i think because the right channel DCSTB is having a slight deviation (LOW through) between + and -)
Nothing audible !
Good weekend everybudy
Jesper
Hello here
so, here is some meassurements.
First DCoffset... please look at secund and third picture. As can be seen level is very low, even at startup. Around 4 seconds for stable DCoffset.
Bias level is checked last, very stable as can seen (Stuborn mule grade bias) as Salas would have called it.
My bias is a bit deviated as can be seen, this is i think because the right channel DCSTB is having a slight deviation (LOW through) between + and -)
Nothing audible !
Good weekend everybudy
Jesper
Attachments
So...
Boxing it up for good now... heat on PSU (Dual dcstb) is ~50C, after ~5hours now.
So to repeat myself, this is going to be a keeper, even if i am a crazy diy guy
Around xmas time i visit some very highend freinds nearby, to have their opiniun... cause mine is perhaps filled with some diypride.... (dontknow for sure about that through)
-seeya'
Jesper.
Boxing it up for good now... heat on PSU (Dual dcstb) is ~50C, after ~5hours now.
So to repeat myself, this is going to be a keeper, even if i am a crazy diy guy
Around xmas time i visit some very highend freinds nearby, to have their opiniun... cause mine is perhaps filled with some diypride.... (dontknow for sure about that through)
-seeya'
Jesper.
Hello.
Though I'm awaiting for my full sets of DGG3 and dual DCSTB's from Tea-Bag, I ordered 5 pieces of uPA68H JFETs from an eBay seller. Just in case I manage to destroy some during build up. I measured them and here's the results. Quite good according to my humble cheap DMM, dont't you think? These JFETs are of the slim type what Salas has posted earlier in this thread. This is just a measurement of one of the individual JFET's both channels (I.1 = channel 1, I.2 = channel 2). My voltage source is only valid from 2,55...19 V. I had 100R resistor in series from voltage source + to JFET's drain and gate-source were connected to voltage source minus.
Though I'm awaiting for my full sets of DGG3 and dual DCSTB's from Tea-Bag, I ordered 5 pieces of uPA68H JFETs from an eBay seller. Just in case I manage to destroy some during build up. I measured them and here's the results. Quite good according to my humble cheap DMM, dont't you think? These JFETs are of the slim type what Salas has posted earlier in this thread. This is just a measurement of one of the individual JFET's both channels (I.1 = channel 1, I.2 = channel 2). My voltage source is only valid from 2,55...19 V. I had 100R resistor in series from voltage source + to JFET's drain and gate-source were connected to voltage source minus.
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So...
Boxing it up for good now... heat on PSU (Dual dcstb) is ~50C, after ~5hours now.
So to repeat myself, this is going to be a keeper, even if i am a crazy diy guy
Around xmas time i visit some very highend freinds nearby, to have their opiniun... cause mine is perhaps filled with some diypride.... (dontknow for sure about that through)
-seeya'
Jesper.
Have you decided the final breathing windows plan or breathing holes pattern artistry on the top?
P.S.
You can make many things with the surplus units like a decent CCSed two FET DC coupled buffer out of each one without matching need for instance. Like they put many local ones in FET active crossovers etc. Or you need to buffer a pot from a BJT input stage base current not to scratch etc.
Yes.
I did just plain classic. -But it's working as supposed.
Real burning amp.
Looks like, it's very steady regarding temperature also. After 1 maybee 2 hours the temperature stays the same.
Btw. I forgot to tell, that this particular fellow i will visit, got a pair of those speakers, which is made by a now closed oneman company. He also got a very expensive power amp. (commercial) Dont know which model http://www.perreaux.com/; I am looking forward to try it on his hifi.
Jesper.
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Sadly true. Thank you for spotting this little gem
Yes, why not?
Now it's up to you, as the 2SK170s are becoming really scarce, maybe you can develop a new DCB1
P.S. in this thread you expressed your intention to revise your SSLV 1.2R and make a pcb. Are you cooking something up in this period?
Maybe dedicated to the DCG3... Should I believe in Santa Claus? 
I mean three early users listen with such big planar technology speakers already (Eminent Technology, Infinity, Apogee) and now your friend's system has alike. So I say what a coincidence among the few early DCG3 adopters circle to be so many big planar dipoles that are not so common to meet in most home hi-fi installations.
Sadly true. Thank you for spotting this little gem
Yes, why not?
Now it's up to you, as the 2SK170s are becoming really scarce, maybe you can develop a new DCB1
P.S. in this thread you expressed your intention to revise your SSLV 1.2R and make a pcb. Are you cooking something up in this period?
Its not as high transconductance as 2SK170 but near and I have in mind to try an overhaul for both classic by now circuits with more easy for today parts and a new twist or two. So the NEC must be considered also.
For the time being I try to fix things as I am not so lucky with the systems lately. My speakers changed frequency response after I moved the crossovers inside and removed the extra cables (parasitics were crucial to the compression driver's alignment it proved). Now I am investigating that by some cabinet diving soldering trials. My Dell computer monitor died, my Dell SFF computer does not have modern video output and it does not accept a proper double width video card for a WQHD 21:9 panoramic I prefer to replace the dead one for the future. I will enlarge the monitor and shrink the computer to save some space and balance the needed funds. I will get an Intel NUC.
So when all is sorted out I will put my head together again and start investigating my new projects. For the time being I am posting this message to you using my 22 inch kitchen TV as a PC monitor.
BTW Jesper, I forgot to ask. That initial spike in your DC offset data log represents the relay click moment in time or you measured before the relay and it represents the power on moment?
It's a short spike, long before relay enagages.
If you look carefully on the sheet, it's only for around ~3sec. EDIT from 1sec. to 3Sec.
This Almemo thing i brought home from work, is soo cool, can meassure 1/100 pro. secunds data log. -I am using it for periodical failure faultclearence on our cranes at Port of Fredericia https://www.adp-as.dk/
Jesper.
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