If you have the new 1794S motherboard, just follow what's written on the PCB.
There is NO mistakes there and you can trust Doede's writings.
The circuit is indeed different to give room to the SPDIF receiver.
no worries, both work fine, nothing get fried.....
that is why I changed to have all 100 ohm, makes kitting easier....
the power supply needs 6 volt extra to have the regulation work.... so for the 5 volt you could do this, for the 12 volt powr supply, you would need 18 volt, or practically two batteries making 24 volt. proof is in the pudding if it will work. like the idea, batteries sound weaker and less open in my experience when DIRECTLY used, so may be with the regulation, that improves? interesting thought....
Thanks, that was my intention to do, a 24 V for DAC and a 12V for the Wave IO
Will publish the results here.
As said in my last "seeking advice" post, I current have 8-decks running smoothly and very enjoyable. I guess I could be happy with its present stage but as it seems, we have the tendency pushing the envelop and look for way to further enhancing our listening experience so here to have some pictures to illustrate it better!
Here is the current DAC:
This is what I am looking for in next couple days. I will report back if adding another 3 will bring any noticeable improvement or worthwhile doing?
Note I have connect the EI tranny as supposed to toroidal. I found using the EI into Doede's ps sound smoother and very relaxing, a very analog sounding.
Here is Stefan's unregulated idea PS which I will be constructing in coming weeks.
The idea is using EI 200VA 2x15V transformer with two secondary in parallel into either Schottky 8TQ100(8A at 100V) or Cree Schottky C3D06065A(5A at 650V), output of the Schottky into a Mundorf M-Resist R1 at 20W, then outputting into Choke(5A at 50mH with R23 resistance). Out from the choke into Mundorf 4700uf which output into second choke of the same specs, then output into 4x Elna Silmic 1000uf and may be with a bleeder resisters, TBA. I also will be adding a small little capacitor ranging 0.01uf to 0.47uf at the secondary EI where it is connecting to the Schottky. So I was told this little cap will minimise back flow of dirty ripple...?
May be you guys can provide the much needed advices on this configuration?
Edit: I emailed Guido for the Shunt regs for 11-DAC boards and mainboard. He has confirmed that my 200VA transformer is more than sufficient running the 47 Shunt regs as each utilises approx 50mA. May be Stefan and James can shed some light with this Shunt idea, please?
Here is the current DAC:
An externally hosted image should be here but it was not working when we last tested it.
This is what I am looking for in next couple days. I will report back if adding another 3 will bring any noticeable improvement or worthwhile doing?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Note I have connect the EI tranny as supposed to toroidal. I found using the EI into Doede's ps sound smoother and very relaxing, a very analog sounding.
Here is Stefan's unregulated idea PS which I will be constructing in coming weeks.
The idea is using EI 200VA 2x15V transformer with two secondary in parallel into either Schottky 8TQ100(8A at 100V) or Cree Schottky C3D06065A(5A at 650V), output of the Schottky into a Mundorf M-Resist R1 at 20W, then outputting into Choke(5A at 50mH with R23 resistance). Out from the choke into Mundorf 4700uf which output into second choke of the same specs, then output into 4x Elna Silmic 1000uf and may be with a bleeder resisters, TBA. I also will be adding a small little capacitor ranging 0.01uf to 0.47uf at the secondary EI where it is connecting to the Schottky. So I was told this little cap will minimise back flow of dirty ripple...?
May be you guys can provide the much needed advices on this configuration?
Edit: I emailed Guido for the Shunt regs for 11-DAC boards and mainboard. He has confirmed that my 200VA transformer is more than sufficient running the 47 Shunt regs as each utilises approx 50mA. May be Stefan and James can shed some light with this Shunt idea, please?
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If you don't like your "Spinal Tap" dac at 11, I can probably take one off your hands.....
Chuz,
Drew.
Chuz,
Drew.
Stacked dacs
I have very limited knowledge of jitter and signal delay. So I have a question about the stacking of dacs in infinite amounts. The motherboard is time and msb/lsb aligning the i2s input signal. The outgoing signal from this process is still subject to the same limitations as as the i2s signal, correct? So, when we stack these dac boards higher and higher, we don't worry about adding jitter or time delay to the further away boards? The signal is generated fresh from the motherboard, but once it's in the connecting wire it's on its own to reach the dac boards, there's no problems with the delay reaching the different dac boards at different times or with any jitter added by the connecting wires getting very long?
The answer is probably simple and obvious but my lack of knowlege prevents me from seeing it!
I have very limited knowledge of jitter and signal delay. So I have a question about the stacking of dacs in infinite amounts. The motherboard is time and msb/lsb aligning the i2s input signal. The outgoing signal from this process is still subject to the same limitations as as the i2s signal, correct? So, when we stack these dac boards higher and higher, we don't worry about adding jitter or time delay to the further away boards? The signal is generated fresh from the motherboard, but once it's in the connecting wire it's on its own to reach the dac boards, there's no problems with the delay reaching the different dac boards at different times or with any jitter added by the connecting wires getting very long?
The answer is probably simple and obvious but my lack of knowlege prevents me from seeing it!
Palmito, check out Doedes refections on this at his site: http://dddac.com/dddac1794_other.html All the Best, Per
Hi Chanh,
I do not understand why you need James or me to shed light on your ps plan; your plan sounds perfect to me!
Just try it out without the small cap and bleeder. Than after you get used to the, much improved, sound you can experiment with the details like bleeder and caps.
Those chokes look good, where did you buy them? What core material is used?
I see there is still room for more dac boards in your housing, Guido will be very happy with you 😀
I do not understand why you need James or me to shed light on your ps plan; your plan sounds perfect to me!
Just try it out without the small cap and bleeder. Than after you get used to the, much improved, sound you can experiment with the details like bleeder and caps.
Those chokes look good, where did you buy them? What core material is used?
I see there is still room for more dac boards in your housing, Guido will be very happy with you 😀
Hello Chanh,
I did mention many times before that most toroidal transformes are not very good for digital gear. If you have a good EI which isn't radiating into the dac circuit or the output transformers you are far better of.
I would always use a bleeder with a choke input to be sure there is always enough current running to make it work as a true choke input.
Please note! Output current from rectifier: 63% of above with condensor input rectifier, 95% of above with
choke input rectifier.
This a one line copy from a pdf file of a lundahl power transformer.
Sincere greetings, edward
I did mention many times before that most toroidal transformes are not very good for digital gear. If you have a good EI which isn't radiating into the dac circuit or the output transformers you are far better of.
I would always use a bleeder with a choke input to be sure there is always enough current running to make it work as a true choke input.
Please note! Output current from rectifier: 63% of above with condensor input rectifier, 95% of above with
choke input rectifier.
This a one line copy from a pdf file of a lundahl power transformer.
Sincere greetings, edward
Hi Stefan,
The chokes I bought from eBay based on Tuyen's recommendation.
Valab 50MH 5A Filter Choke Amorphous Metglass Double C Core UTC Triad 300B | eBay
They are fragilely brittle. I will place them in a cast iron case as safety measure. I did place the choke in Doede's PS R1 position with pleasant result. Sound has certainly become more fluid and with weight/body. Btw, these chokes weight approx 2.5kg each.
The chokes I bought from eBay based on Tuyen's recommendation.
Valab 50MH 5A Filter Choke Amorphous Metglass Double C Core UTC Triad 300B | eBay
They are fragilely brittle. I will place them in a cast iron case as safety measure. I did place the choke in Doede's PS R1 position with pleasant result. Sound has certainly become more fluid and with weight/body. Btw, these chokes weight approx 2.5kg each.
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Well I'm happy to report 2 big breakthroughs here today! 🙂
First is I switched my new power supply back to choke input, only this time I wired in the first choke correctly in series as per the datasheet, then the second choke I wired in common mode rejection mode with the v+ through one winding and the gnd through the other. I currently have 2 x 2,200uf Panasonic FM after each choke and a 57R bleeder after the first choke. With a 2 x 12v transformer, I get 12.3v into the first choke and 11.24v after the second choke. I had already bridged R2/R4 and L3/L3 on the dac board, but I had to also reduce R1/R3 down to 6ohm instead of 10ohm to give me 10.3v at the 8v regs. Well, wow! I really like how that sounds. Very lucid and up front with good body and great detail. Very nice indeed.
But the background interference noise was still really bugging me, so after trying going around the house turning almost every single other electrical thing off and still having the noise, I go back to the start again. To cut a long story short, that horrible noise was almost entirely caused by the ethernet cable into the raspberry pi transmitting noise into the dac over the I2S cables... I had ruled out the sound coming from the pi fairly early on by unplugging the power from it and noticing no difference, but I hadn't thought to pull the ethernet cable
and recently I haven't been running with the I2S isolator 🙄 The ethernet connection in both places I've been testing the DAC is plugged into a powerline adapter attached to the mains. So I still think the noise comes from horrible dirty mains, but it's being transmitted direct into the dac via the ethernet cable 🙄 Well, that's an easy problem to fix, so I've swapped back to using wifi and wow! The noise has almost entirely dropped off. It's now 5-10% of what it was before and the details are really shining through now. Very happy indeed 😀 With this new power supply and the shunt regs sat so close to the DAC chip where I have them mounted now, it's certainly the best I've ever heard it.
Happy days. loving the music 😎 thanks again to Doede for providing the difficult bits to make this all happen and to you guys here for the inspiration and guidance 🙂
First is I switched my new power supply back to choke input, only this time I wired in the first choke correctly in series as per the datasheet, then the second choke I wired in common mode rejection mode with the v+ through one winding and the gnd through the other. I currently have 2 x 2,200uf Panasonic FM after each choke and a 57R bleeder after the first choke. With a 2 x 12v transformer, I get 12.3v into the first choke and 11.24v after the second choke. I had already bridged R2/R4 and L3/L3 on the dac board, but I had to also reduce R1/R3 down to 6ohm instead of 10ohm to give me 10.3v at the 8v regs. Well, wow! I really like how that sounds. Very lucid and up front with good body and great detail. Very nice indeed.
But the background interference noise was still really bugging me, so after trying going around the house turning almost every single other electrical thing off and still having the noise, I go back to the start again. To cut a long story short, that horrible noise was almost entirely caused by the ethernet cable into the raspberry pi transmitting noise into the dac over the I2S cables... I had ruled out the sound coming from the pi fairly early on by unplugging the power from it and noticing no difference, but I hadn't thought to pull the ethernet cable
and recently I haven't been running with the I2S isolator 🙄 The ethernet connection in both places I've been testing the DAC is plugged into a powerline adapter attached to the mains. So I still think the noise comes from horrible dirty mains, but it's being transmitted direct into the dac via the ethernet cable 🙄 Well, that's an easy problem to fix, so I've swapped back to using wifi and wow! The noise has almost entirely dropped off. It's now 5-10% of what it was before and the details are really shining through now. Very happy indeed 😀 With this new power supply and the shunt regs sat so close to the DAC chip where I have them mounted now, it's certainly the best I've ever heard it. Happy days. loving the music 😎 thanks again to Doede for providing the difficult bits to make this all happen and to you guys here for the inspiration and guidance 🙂
Hello James,
So nice to read you are loving it.
Did you have a reason for using common mode for the second choke and not for the first one?.
Did you see the link i posted a few days back about where to connect the ground .
I would think the sooner the better so have the common mode closer to the transformer. But maybe your choice is better.
I just did order the R core in france.
Chanh has some nice chokes i like the low dc resistance. i think that is a big plus. But inductance isnt very high so you need to draw more current to have a true choke input.
Sincere greetings, Edward sorry link is in dutch but just look at the pictures
http://www.dhtrob.com/impressies/afbeeldingen/common_mode_choke_ae_psu.gif
So nice to read you are loving it.
Did you have a reason for using common mode for the second choke and not for the first one?.
Did you see the link i posted a few days back about where to connect the ground .
I would think the sooner the better so have the common mode closer to the transformer. But maybe your choice is better.
I just did order the R core in france.
Chanh has some nice chokes i like the low dc resistance. i think that is a big plus. But inductance isnt very high so you need to draw more current to have a true choke input.
Sincere greetings, Edward sorry link is in dutch but just look at the pictures
http://www.dhtrob.com/impressies/afbeeldingen/common_mode_choke_ae_psu.gif
Thanks Edward. Yes, I saw that and I have used this setup with my star grounding after the CM choke. Thanks.
Why the second choke? Well, I don't have a lot of experience with these things, but it seemed to me that the first choke is working hard, whereas the second one has an easier job, so will be less effected by only using half the winding for the v+. That's my thinking anyway, I'm happy to be corrected if anyone knows better 🙂
@ChanH, that sounds cool. 47 shunts is a mega install! I'm very happy with 1 deck 🙂 I'd be very interested to compare and to see how you get on. I can see how the standard regulator is not so accurate and can hugely benefit from parallel processing with extra dac decks, but I would imagine that based on the fact that a shunt regulated dac deck is much more accurate to begin with, I would expect to see smaller gains from adding more and more extra shunted decks as your starting point is much higher accuracy. That's only my theory though, I'd be interested to see how you get on. I would recommend mounting the shunts as close to the DAC chip as you can rather than at the standard regulator positions. I feel that has helped with mine. If I was going to order a huge load of shunt regs, I would ask for them to not have the header pins mounted as then it's easier to set them up where you want them without having to desolder them all first. Good luck! 🙂
Why the second choke? Well, I don't have a lot of experience with these things, but it seemed to me that the first choke is working hard, whereas the second one has an easier job, so will be less effected by only using half the winding for the v+. That's my thinking anyway, I'm happy to be corrected if anyone knows better 🙂
@ChanH, that sounds cool. 47 shunts is a mega install! I'm very happy with 1 deck 🙂 I'd be very interested to compare and to see how you get on. I can see how the standard regulator is not so accurate and can hugely benefit from parallel processing with extra dac decks, but I would imagine that based on the fact that a shunt regulated dac deck is much more accurate to begin with, I would expect to see smaller gains from adding more and more extra shunted decks as your starting point is much higher accuracy. That's only my theory though, I'd be interested to see how you get on. I would recommend mounting the shunts as close to the DAC chip as you can rather than at the standard regulator positions. I feel that has helped with mine. If I was going to order a huge load of shunt regs, I would ask for them to not have the header pins mounted as then it's easier to set them up where you want them without having to desolder them all first. Good luck! 🙂
Hello James,
The second choke has an easier job but to me both windings are working. The first choke has a hard life because there is a lot of tension across it. If you compare cap input and choke and input and you will wonder where did all the voltage go?
Next thing to do will be optimum placement of all the magnetics components. Sometimes twisting some wires or shortening them could give some benefits.
Maybe you can use the scope to see if the first one should be the common mode.
Because the currents are rather big. The wiring is crucial.
Also because it is digital gear you should also think about '' digital garbage'' given back to the net and your other gear.
Sincere greetings, edward
The second choke has an easier job but to me both windings are working. The first choke has a hard life because there is a lot of tension across it. If you compare cap input and choke and input and you will wonder where did all the voltage go?
Next thing to do will be optimum placement of all the magnetics components. Sometimes twisting some wires or shortening them could give some benefits.
Maybe you can use the scope to see if the first one should be the common mode.
Because the currents are rather big. The wiring is crucial.
Also because it is digital gear you should also think about '' digital garbage'' given back to the net and your other gear.
Sincere greetings, edward
Hi DDDAC people,
I hope one of you have experience with this ... I'm currently finishing a DDDAC inspired PCM1794 DAC yet am considering replacing the 47 uF Vcom Muse capacitors with some of higher value. The Vcom capacitors are those that decouple the internal bias for the right and left channels ...
Have one/some of you experience with increasing the value of these capacitors?
Thanks for any experiences you may be able to share ;-)
Jesper
I hope one of you have experience with this ... I'm currently finishing a DDDAC inspired PCM1794 DAC yet am considering replacing the 47 uF Vcom Muse capacitors with some of higher value. The Vcom capacitors are those that decouple the internal bias for the right and left channels ...
Have one/some of you experience with increasing the value of these capacitors?
Thanks for any experiences you may be able to share ;-)
Jesper
I'd be interested in this too
Would 100 to 3 00 uf caps have any benefits
And if any type of smd caps would be suitable
input motherboard cinch or bnc
Hello,
I did start collecting some parts. In my present set up both my cd player and dac are using canare 75 ohm to get them connected. I dont wanna start using bnc/rca adapters so i was thinking about getting the bnc connector to mount on the motherboard. It might be at 90 degrees but that is okay for me.
I always did read that most rca plugs are not the best for true 75 ohm connection. This dac having so much attention to detail why not use the bnc?
I did already order a 300va r-core 2*15 volts for choke input and also a r-core 2 times 20mH 2.5A choke which could be used in common code connection. I bought it because it was promotion.
But will probably go for a ll2733 in common mode right after the rectifier and a ll1694 after the first cap.
Sincere greetings, edward
Hello,
I did start collecting some parts. In my present set up both my cd player and dac are using canare 75 ohm to get them connected. I dont wanna start using bnc/rca adapters so i was thinking about getting the bnc connector to mount on the motherboard. It might be at 90 degrees but that is okay for me.
I always did read that most rca plugs are not the best for true 75 ohm connection. This dac having so much attention to detail why not use the bnc?
I did already order a 300va r-core 2*15 volts for choke input and also a r-core 2 times 20mH 2.5A choke which could be used in common code connection. I bought it because it was promotion.
But will probably go for a ll2733 in common mode right after the rectifier and a ll1694 after the first cap.
Sincere greetings, edward