OK, but pretty much does not matter, because the testing environment was most probably with low impedance Rinput=10K cca, done?
.
I persume that You measure ot because the value of Vb=320V You are familiar with... 🙂
.
ECC40 have 1/4 -db even with 220K Rin next device. And That is some minimal value. So for Tube devices that has ususaly more than that 470K to 1meg is OK. Another thing is High ECC40 (single section) output resistance. But that probably will satisfy dynamic capacitances of next Tube stage...
.
And 22K load is for ECC40 does not mean that is OK for 6SN7 for instance?
.
I can simulate for more precise results.
I miss that T.L. post? Could You point me to?
Anyway it is very good even with very low Riv value as 10-12 ohms (TDAs).
I simulated some advanced version of double SRPP with ECC83 dual sections for amplification tube and ECC88 as high tranconductance tube cascoded in ECC83 anode circuit. With exeptional results, baring in mind huge amplification number...
And low output resistance too, with odeg phase.
BUT needs Vb of slight more than 400V. That will creates a issue fir DIYers in advance...
.
Mu Followers are with pentode as sort of specific ampli triode anode load. And they are slightly complicated, few passive elements more.
But they are also very good.
.
And not "mixed" design, but all-tube.
.
PS
I think that is somehow a key for considering DA segment maybe to have a high input impedance buffer after Riv,
Then isolation 1:1 Transformer. (No squared transfer between Prim annd Sec.!)
Buffer with high input impedance JFET or even low voltage tube, can be suplied from already DA DAC segment, and have low output impedance to drive huge BW isolation transformer. With low signal transformer will not distort and can be from lower Hy because of very low impedance from buffer source...
.
Other concept is ti have some current circuit that will bring Io to external RIV and make I-V conversion outside of DAC, leaving DAC loaded with high imedance and not reactive load... That will be grounded grid topology. And again, 1:1 isolation transformer to bring back tha phase to 0deg. The output impedance is same as that Riv used so it is low and transformer is not complicated.
.
All after that galvanic isolation, is pure Analog domain. Inclouding PS used. And ofcourse Tube can do the amplification job from transformer secondary.
.
With all other concepts we have mix mode of AD to pure A power, and with huge step up transformers transfer to DAC ratio from Sec to Prim is huge because it is squared... 🙂
.
Anyway it is very good even with very low Riv value as 10-12 ohms (TDAs).
I simulated some advanced version of double SRPP with ECC83 dual sections for amplification tube and ECC88 as high tranconductance tube cascoded in ECC83 anode circuit. With exeptional results, baring in mind huge amplification number...
And low output resistance too, with odeg phase.
BUT needs Vb of slight more than 400V. That will creates a issue fir DIYers in advance...
.
Mu Followers are with pentode as sort of specific ampli triode anode load. And they are slightly complicated, few passive elements more.
But they are also very good.
.
And not "mixed" design, but all-tube.
.
PS
I think that is somehow a key for considering DA segment maybe to have a high input impedance buffer after Riv,
Then isolation 1:1 Transformer. (No squared transfer between Prim annd Sec.!)
Buffer with high input impedance JFET or even low voltage tube, can be suplied from already DA DAC segment, and have low output impedance to drive huge BW isolation transformer. With low signal transformer will not distort and can be from lower Hy because of very low impedance from buffer source...
.
Other concept is ti have some current circuit that will bring Io to external RIV and make I-V conversion outside of DAC, leaving DAC loaded with high imedance and not reactive load... That will be grounded grid topology. And again, 1:1 isolation transformer to bring back tha phase to 0deg. The output impedance is same as that Riv used so it is low and transformer is not complicated.
.
All after that galvanic isolation, is pure Analog domain. Inclouding PS used. And ofcourse Tube can do the amplification job from transformer secondary.
.
With all other concepts we have mix mode of AD to pure A power, and with huge step up transformers transfer to DAC ratio from Sec to Prim is huge because it is squared... 🙂
.
Hello Zoran,
I copy the post here :
6N6/6N30/5687WB (pins are a LITTLE different!) with E-822 (8.2mA) CRD or whatever is desired as current in the cathode as upper part, extra MOSFET CCS to pull more current out of the cathode.
Then our signal tube below.
Maybe 4 sockets for the signal tube(s), 2 x 7pin for 6AK5, 1 x 9 pin for 5670 and 1 x 9 pin for ECC88 style tubes. Connect grids dnd snodes together, separate cathode resistors to get bias "just so".
And one more 9 pin socket for 6N30/5687 with a switch to select.
We could add a set of small piggyback I/U conversion PCB's with three options:
Resistor I/U conversion with bjt current conveyor to +5V
Resistor I/U conversion with bjt current conveyor to -15V
Resistor I/U conversion with BJT low noise 2mA offset CCS and resistor between AoL/R and AGND.
I will send an E-Mail later today (Monday) to everyone who I know is working on a PCB, so we can pool efforts. Anyone who has been beavering away in lucubrations on the same job, but hasn't told anyone, please PM me so I can bring you in.
Thor"
I copy the post here :
I would suggest 6N3/5670 or even better 6J1/6AK5 instead. Hybrid Mu... Hmmm. Make it a real one please.
6N6/6N30/5687WB (pins are a LITTLE different!) with E-822 (8.2mA) CRD or whatever is desired as current in the cathode as upper part, extra MOSFET CCS to pull more current out of the cathode.
Then our signal tube below.
Maybe 4 sockets for the signal tube(s), 2 x 7pin for 6AK5, 1 x 9 pin for 5670 and 1 x 9 pin for ECC88 style tubes. Connect grids dnd snodes together, separate cathode resistors to get bias "just so".
And one more 9 pin socket for 6N30/5687 with a switch to select.
We could add a set of small piggyback I/U conversion PCB's with three options:
Resistor I/U conversion with bjt current conveyor to +5V
Resistor I/U conversion with bjt current conveyor to -15V
Resistor I/U conversion with BJT low noise 2mA offset CCS and resistor between AoL/R and AGND.
I will send an E-Mail later today (Monday) to everyone who I know is working on a PCB, so we can pool efforts. Anyone who has been beavering away in lucubrations on the same job, but hasn't told anyone, please PM me so I can bring you in.
Thor"
I wish you all new year 2025 full of endless possibilities, boundless joy, full of love and unforgettable moments, enjoy DACs! 😊 🎆🎇
Same to you Miro! And many thanks for all your contributions to the community. Cheers!
Many thanks Miro! Best wishes to you and extra thanks for all your efforts for the community!
Take care
Claude
Take care
Claude
Thanks to @eclipsevl for his creation of York + reclocker board.
Now DIYers have more option for a nice, compact solution for USB interface.
I configured it for NOS DAC, RJ, 20-bit easily with the configuration tool. No hardware configuration is involved, which is what I like about this little board. Magically configurable to various applications, this flexibility is an important plus point to me.
Certainly better sounding than my legit version of Amanero Combo 384. The Amanero sounds a little crispier and thinner
York fills out the music, more bloom and body. Most importantly, it has a footprint that is compatible with my JLSounds - PCM63P stack.
Now DIYers have more option for a nice, compact solution for USB interface.
I configured it for NOS DAC, RJ, 20-bit easily with the configuration tool. No hardware configuration is involved, which is what I like about this little board. Magically configurable to various applications, this flexibility is an important plus point to me.
Certainly better sounding than my legit version of Amanero Combo 384. The Amanero sounds a little crispier and thinner
York fills out the music, more bloom and body. Most importantly, it has a footprint that is compatible with my JLSounds - PCM63P stack.
Hi All,
I don't know much about electronics.
Can I use 0.22uf caps instead of 0.1uf for C5, C6 and C7?
I bought 100 of 0.22uf caps at a flea market for a very good price of $7 and I'm hoping I can use them here.
Thanks.
I don't know much about electronics.
Can I use 0.22uf caps instead of 0.1uf for C5, C6 and C7?
I bought 100 of 0.22uf caps at a flea market for a very good price of $7 and I'm hoping I can use them here.
Thanks.
I am not much of a cable person, especially for USB cables, LAN cables, power cords, AC plugs/sockets and what not. I simply bought what i thought is decent and with required specifications, plug them in and forget about them.
I replaced output caps in Michelag's tube IV with ClarityCap CMR 8.2uF 400Vdc and the difference is significant - it was obvious from the moment I turned the musin on. Its more pleasant to listen, better presence, more natural tonality, better low end, better details. Nothing surprising really, just wanted to share.
@Seavan need to have a look at a distributor from this side of the pond, and of course the price.
Apropos, I'm working on Grunf s more refined (shunt regulated through jfet opamp) tube b+ 😁
Not that I really need it, but it is a useful add-on for other projects...
Is someone interested in it? 🤣
Apropos, I'm working on Grunf s more refined (shunt regulated through jfet opamp) tube b+ 😁
Not that I really need it, but it is a useful add-on for other projects...
Is someone interested in it? 🤣
It is pricey, not as much as other options though. I got it from https://partsconnexion.com/claritycap-capacitor-8-2uf-400vdc-cmr-series/ and it was $51 a piece just 2 weeks ago. Keep in mind - it's HUGE!
I am using Salas HV shunt supply right now. TBH, I cannot tell much difference from your RC supply. I am interested in your new supply! It would be fun to try.
I am using Salas HV shunt supply right now. TBH, I cannot tell much difference from your RC supply. I am interested in your new supply! It would be fun to try.