To expand a bit on my reply re output options:
IME the best output options are as follows by destination:
1. SE Preamp
-Sowters (offering lower noise if high efficiency speakers used)
-Tube output stage
2. Balanced Tube Preamp Using Input Transformers
-Capacitor
3. Balanced Solid State Preamp With Blocking Caps
-Direct
4. Balanced Solid State Preamp No Blocking Caps
-Sowters
IME the best output options are as follows by destination:
1. SE Preamp
-Sowters (offering lower noise if high efficiency speakers used)
-Tube output stage
2. Balanced Tube Preamp Using Input Transformers
-Capacitor
3. Balanced Solid State Preamp With Blocking Caps
-Direct
4. Balanced Solid State Preamp No Blocking Caps
-Sowters
Hi Folks, have just purchased a DDDAC 1794S with Tent clock and single board (from user on another forum) and when testing it get a cracking between tracks and some tracks just crackle all the way through. The DDDAC is connected via coax from a Bluesound Node 2i and out to a pre-amp. All music where I get this crackling from is via Amazon music. When I try the Innuos Zen Mini mk3 (CD ripped music) there is no cracking.
If anyone knows about this issue and the fix it would be good to know otherwise I need to return it and look for a different DAC. I have seen other posts in this thread regarding crackling noises but looks like it’s related to Kali or USB. At the moment I am just looking at simple DAC operation with coax in and rca out. Thanks in advance.
If anyone knows about this issue and the fix it would be good to know otherwise I need to return it and look for a different DAC. I have seen other posts in this thread regarding crackling noises but looks like it’s related to Kali or USB. At the moment I am just looking at simple DAC operation with coax in and rca out. Thanks in advance.
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Found the issue with the Node 2i being a digital out that is somehow faulty. DDDAC was working fine.
Sure, I see a double power supply and hence powering the DAC in double mono.
If you want to go double mono, have you considered using two DACs incl Mainboard and modify the Mainboard a little, re-wiring the LR signal, so you have a full Right DAC and a LEFT DAC, utilizing both channels and paralleling the outputs ?
The extra would only be an additional Mainboard
If you want to go double mono, have you considered using two DACs incl Mainboard and modify the Mainboard a little, re-wiring the LR signal, so you have a full Right DAC and a LEFT DAC, utilizing both channels and paralleling the outputs ?
The extra would only be an additional Mainboard
I plan:
Will it work properly?
- modify Dac board to separate +Vb for Right channel and +Vb for left channel
- only one Mainboard - modify for power only Right Channel {left side of PCB dddac}
- One PS for one Maniboard and Right Chanel( left part of PCB dddac )
- One PS for for Left Channel(right part of PCB dddac)
Will it work properly?
Will it be enough if the GND of both power sources is connected only in the place marked in the picture?
Gnd for Right Channel Dac and Mainboard will be common. GND for left channel will be separately,connected to right side of dac board.
Ok, I see the need for split power supplies. For 8 boards and more it makes sense to add a Resistor on top of the boards between BCK wire entry and Ground to terminated the signal. It is not critical. I used 220 ohm till 1k - start high and lower if needed. if you do not do this, you might get some crackle in the sound. This will load the VHCT244 chip output and makes the BCK signal more stable an rugged. I tested this with 12 boards
Thank you Doede I see this small drawing error.
GND on MainBoard does not connect to the gnd of the power supply?
If I understand you correctly, I will only connect the resistor to the upper dac board between BCK and ground.
Yes correct, only one time for the whole stack, left side and right side of the top DAC board
Yes the ground connection is now underneath and in between the lowest DAC board and the Mainboard. These GND connections of course will stay, only cut VB or just not use it… both results in the same. I am sure you get it
I just realized; it is already 10 years ago I designed the first version of the DDDAC1794! 
So, I thought it to be a good idea to write a short chronicle of the DDDAC history and also create a tweaking and upgrade Guide
Go to my Blog Site to read the article!
also......
See you maybe on Feb 4th in Hengelo at the "Luisterdag" Audio event?
I will be there with my Clio setup to measure Loudspeakers for those who are interested...
Audio Event Info on Dutch audio forum
So, I thought it to be a good idea to write a short chronicle of the DDDAC history and also create a tweaking and upgrade Guide
Go to my Blog Site to read the article!
also......
See you maybe on Feb 4th in Hengelo at the "Luisterdag" Audio event?
I will be there with my Clio setup to measure Loudspeakers for those who are interested...
Audio Event Info on Dutch audio forum