DAC AD1862: Almost THT, I2S input, NOS, R-2R

Another Miro AD1865 is in operation. My friend did it up to 90%, I just completed the wiring. Power supplies for the analog part are LT1963/3015, for the digital part LM1117T. It has everything and anything, USB, Toslink, SPDIF, and Bluetooth. BT is turned off when not in use, so it doesn't send interference to the rest of the circuit. USB board is JLSounds, SPDIF board is AK4113. The BT module has an SPDIF output, connected to one of the two SPDIF inputs of the AK4113 board. Opamp is Burson V6 Vivid dual + adapter dual/single. That opamp gives a slightly softer sound in this combination, I prefer the rougher sounding Sparkos SS3602 with the AD1865.
 

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Another Miro AD1865 is in operation. My friend did it up to 90%, I just completed the wiring. Power supplies for the analog part are LT1963/3015, for the digital part LM1117T. It has everything and anything, USB, Toslink, SPDIF, and Bluetooth. BT is turned off when not in use, so it doesn't send interference to the rest of the circuit. USB board is JLSounds, SPDIF board is AK4113. The BT module has an SPDIF output, connected to one of the two SPDIF inputs of the AK4113 board. Opamp is Burson V6 Vivid dual + adapter dual/single. That opamp gives a slightly softer sound in this combination, I prefer the rougher sounding Sparkos SS3602 with the AD1865.
I have the ad1865 an ad811 output, it's my companion on the desk at work... Did you try the ad811?
 
Hi there. I have been following this thread for some time and started building a 1865 DAC. I also have @grunf 's and @Michelag 's tube IV stage.
Re. the IV stage, looking at the pictures in this post:
  • I see that the tube transformer has a 170V , 130mA secondary for the plate. I think I was given a 130V, 150mA recommendation, but I have a hard time finding a transformer with those specs, plus filament secondaries. I like Hammond transformers and was wondering if any in this list would work. What would be the recommended specs?
  • If I use the tube I/V I guess I can bypass the opamps... and everything downstream? Shall I connect the IOUT pin of the chip directly to the I/V stage input?
  • As to the input: I am planning to hook this up to a Raspberry Pi (no Volumio or such, just ArchLinux running MPD) over I2S via GPIO pins. Do I need the shift registers?
Thanks for your help, I'm still new with digital sources. I also have a couple of 1862 and a TDA1541, and might build different boards (and maybe a different tube stage) to compare.
 
Hi there. I have been following this thread for some time and started building a 1865 DAC. I also have @grunf 's and @Michelag 's tube IV stage.
Re. the IV stage, looking at the pictures in this post:
  • I see that the tube transformer has a 170V , 130mA secondary for the plate. I think I was given a 130V, 150mA recommendation, but I have a hard time finding a transformer with those specs, plus filament secondaries. I like Hammond transformers and was wondering if any in this list would work. What would be the recommended specs?
  • If I use the tube I/V I guess I can bypass the opamps... and everything downstream? Shall I connect the IOUT pin of the chip directly to the I/V stage input?
  • As to the input: I am planning to hook this up to a Raspberry Pi (no Volumio or such, just ArchLinux running MPD) over I2S via GPIO pins. Do I need the shift registers?
Thanks for your help, I'm still new with digital sources. I also have a couple of 1862 and a TDA1541, and might build different boards (and maybe a different tube stage) to compare.
For part 1 you can try these, cheap and working. No idea about impact of new Tariffs.
R Core 1
R Core 2

For part 2 I think you could safely connect the IOUT of AD1865 with Michelag's Tube IV
For Part 3, while I have experimented RPI with Delta Sigma DACs 24 bit and higher, but not with R2R for a continuous usage, yet I got the sound working, but it wasn't something I'd prefer to use because of the jitter issues.

I hope other users could shed light on the topic.
 
I wasn't overly happy with the sound, and last night I desolder some regular noname metal film resistors for the RIV and installed the DALE 3.01k RN55D. What a transformation, this is now a completely different DAC. Need to get DALE 47ohm for these output resistors too, and replace these nonames. At the moment I have nothing with so little resistance from DALE.
 

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Hi there. I have been following this thread for some time and started building a 1865 DAC. I also have @grunf 's and @Michelag 's tube IV stage.
Re. the IV stage, looking at the pictures in this post:
  • I see that the tube transformer has a 170V , 130mA secondary for the plate. I think I was given a 130V, 150mA recommendation, but I have a hard time finding a transformer with those specs, plus filament secondaries. I like Hammond transformers and was wondering if any in this list would work. What would be the recommended specs?
  • If I use the tube I/V I guess I can bypass the opamps... and everything downstream? Shall I connect the IOUT pin of the chip directly to the I/V stage input?
  • As to the input: I am planning to hook this up to a Raspberry Pi (no Volumio or such, just ArchLinux running MPD) over I2S via GPIO pins. Do I need the shift registers?
Thanks for your help, I'm still new with digital sources. I also have a couple of 1862 and a TDA1541, and might build different boards (and maybe a different tube stage) to compare.

point 1,
[th][/th]​
[td]
26​
[/td][td]
120V @ 140 ma​
[/td]​
this would work, but the CCS has only 68V to work. I prefer to double the plate voltage.
Have a look at Rehan's links for the transformer,

point 2,
i take the sound from pins 2 and 3 (signal and ground) of the opamps holes.

point 3,
anything outputting I2S needs shift registers. you can bypass them ONLY if you have got a CPLD signal consisting of CLK, Latch, Data Left and Data Right.
 
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