Hi Kartick, this question is answered in Doede’s documentation on his DDDAC site.
Total current for 4 decks with tent shunt is roughly 0,9 A. I always count with 1A
Hey DD, firstly my boards are the early designs, not the tent shunt ones. Secondly, i was enquiring about how much current does the 4 deck version ouput? I guess that would be in mA and not the 0.9A you said. That is i think the current requirement of 4 boards to be powered up by a PSU. Right?
Yes, want to know the output current. Would have been better if rather than medical conditions, you would have given the answer to my question
My 2 cents
I tried a c3m tube output stage (great tube imho) and I liked it a lot but I prefer the sowters to that. I also did some a/b testing against some dac‘s and my heavily modified dddac (own mainboard and no regulators on the dac boards) and the dddac was very hard (I couldn’t) to differentiate from a very expensive nos dac with 45 tubes in the output stage. 2 other dacs in the test had quite a different sound. So I wouldn’t generalize anything anymore
A good implemented tube output will surely work, probably also system and taste dependent.
Greetings
I tried a c3m tube output stage (great tube imho) and I liked it a lot but I prefer the sowters to that. I also did some a/b testing against some dac‘s and my heavily modified dddac (own mainboard and no regulators on the dac boards) and the dddac was very hard (I couldn’t) to differentiate from a very expensive nos dac with 45 tubes in the output stage. 2 other dacs in the test had quite a different sound. So I wouldn’t generalize anything anymore
A good implemented tube output will surely work, probably also system and taste dependent.
Greetings
I've AB'd the DDDAC with tube output stage against the Cinemags, Sowters, JFET output stage, caps only and every time the tube output stage wins hands down. Of course it depends what tube output stage and I make mine with 6SL7s. Sowters are closest.........
Let me give my 2 cents on this myth of "Tube Output Stages" and why there is no real consensus .
The DDDAC design has an output level 1,2Vrms in single ended or 2.4V rms in balanced. So there is NO NEED to amplify this any further to make it compatible with any pre amp or power amp. Most power amps have a gain > 20x this would result in ~ 300Watt power in 8 Ohm speakers when driven balanced directly into a power amplifier
so I see a "tube output stage" is probably the same as when you connect the DAC to a tube preamplifier (Like I do with Cleo 7 and than into power amplifiers with gain 1x)
WHY would you go through the effort of making a complex and expensive tube stage (Tube rectifier, CLC, Expensive capacitors etc) to add no gain? (remember you do not NEED this)
OK, if you need a pre amplifier than it is clear, but calling this a tube output stage for the DAC is not necessary.
Well, i think you get the point.
Now adding a tube buffer is also not "needed" the Output impedance of the DDDAC with passive I/R is low enough for most applications and a Tube Buffer does not have lower impedance either: at Id=30mA (wow BIG cathode follower) output impedance is like 33 Ohm and that is like 4 DDDAC decks....
any way, it is a hobby and when someone likes a tube stage after the DAC, than you are right of course. At the end it is about what we like listening to music.
Technically however, there is no NEED for it.
my 2 cents
The DDDAC design has an output level 1,2Vrms in single ended or 2.4V rms in balanced. So there is NO NEED to amplify this any further to make it compatible with any pre amp or power amp. Most power amps have a gain > 20x this would result in ~ 300Watt power in 8 Ohm speakers when driven balanced directly into a power amplifier
so I see a "tube output stage" is probably the same as when you connect the DAC to a tube preamplifier (Like I do with Cleo 7 and than into power amplifiers with gain 1x)
WHY would you go through the effort of making a complex and expensive tube stage (Tube rectifier, CLC, Expensive capacitors etc) to add no gain? (remember you do not NEED this)
OK, if you need a pre amplifier than it is clear, but calling this a tube output stage for the DAC is not necessary.
Well, i think you get the point.
Now adding a tube buffer is also not "needed" the Output impedance of the DDDAC with passive I/R is low enough for most applications and a Tube Buffer does not have lower impedance either: at Id=30mA (wow BIG cathode follower) output impedance is like 33 Ohm and that is like 4 DDDAC decks....
any way, it is a hobby and when someone likes a tube stage after the DAC, than you are right of course. At the end it is about what we like listening to music.
Technically however, there is no NEED for it.
my 2 cents
Last edited:
I just started a new thread
handy-management-module-ultra-capacitors
Might be of interest for any DIY who would like to connect a large Ultracap Bank at the DDDAC 12 Volt input
handy-management-module-ultra-capacitors
Might be of interest for any DIY who would like to connect a large Ultracap Bank at the DDDAC 12 Volt input
Hello,
You should decide yourself!!
You can start with one stack and a nice Russian output cap.
If you like it you will already have nice music and then one year later you can add extra board(s)
Audio creative has a new transformer that ( i think) can also work with less than 4 board.
Greetings, Eduard
You should decide yourself!!
You can start with one stack and a nice Russian output cap.
If you like it you will already have nice music and then one year later you can add extra board(s)
Audio creative has a new transformer that ( i think) can also work with less than 4 board.
Greetings, Eduard
An active output stage with a differential output (tube or not) might be a cost-effective and high-performance alternative to a transformer. If you're running one or two decks only, an output stage with some current gain (i.e., high input impedance and low output impedance) might be beneficial. But hey, I never tried it since my DDDACs all have 4 decks or more coupled to a Sowter TVC, and I couldn't be happier
Just start with a single deck and some cost-effective output capacitors (I do NOT recommend the expensive exotica caps!). You'll be very happy with this setup for a long time, and once you are out of the student-no-money mode you can still consider upgrading to more DAC decks and output transformers and stuff.
An active output stage with a differential output (tube or not) might be a cost-effective and high-performance alternative to a transformer. If you're running one or two decks only, an output stage with some current gain (i.e., high input impedance and low output impedance) might be beneficial. But hey, I never tried it since my DDDACs all have 4 decks or more coupled to a Sowter TVC, and I couldn't be happier
One reason is indeed cost. But it also sounds better than the Sowters according to a panel of audio afficionados I recruited for A/B testing. It also gives the option of running direct into a power amp with some volume control device. Sometimes the technical explanation or theory doesn't match the practice....
But as Doede says, it's a hobby so try it out and take your pick
For me the sweet spots are two or four DDDACs. If you make your own valve output stage then you have a great-sounding DAC. One of mine-my own power supplies and tube output stage-sounded as good as a £50k record deck we had it up against on decent recordings