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

DATA is differential with DATA+ and DATA- on pins 1 and 3. The same for LRK+ and LRK- on pins 7 and 9 on the LVDS standard.
Hooked up BCK and tried all combinations for DATA and LRK as input i.e. DATA+/LRK+, DATA-/LRK+, DATA+/LRK- and DATA-/LRK-.

Nothing made any sound. I assume I need a LVDS differential receiver to make it work.

Didn't know what I was looking for but hooked up the scope, had a square 44.1K Hz waveform on the clocks and DATA had some squiggly stuff which changed on play/pause from the streamer so something was happening.
 
Another PCM63 DAC lives! DIR9001 into miro1360 pcm and Lundahl output stage, with Sparkos PSU

Ran into one issue with setup and I'm looking for feedback. Is 24bit I2S a requirement? My initial test
resulted in no low bass with a 16bit SPDIF signal. Setting output to 24bit via SMSL PO100 from my PC
finally resulted in a full audio bandwidth. I see most people are using I2SoverUSB or something similar.
Do I need a different SPDIF to I2S board that supports 16bit I2S? I'd like to use my high quality 16/44
CD transport if possible. Thanks!
 

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Warning!! Addiction is highly possible…
That's my secret cap, I'm always addicted.

After some testing I'm liking the IV resistor and transformer setup more than opamp, sounds cleaner to my ears. I used a 12Ω resistor and 1:25 step up transformer. And as a tube addict I gave this dac a tube stage, dacs love tube stages. Being serious, the super high tube input impedance makes this setup possible since the dac output is 7.5KΩ. 2.2Vrms output now of pure DHT goodness.
20230915_101939.jpg


Just the power amp left to figure out.
 
@Brijac
PCM63 out : IV resistor : Trans: d3a?
I have some d3a in my drawer too.
Unfortunatelly we cannot skip riv. But fortunatelly we can reduce the resistance a lot, which sounds much better than larger resistance. I've yet to see which schematic to implement, or design a new one. I haven't seen pcm63 with those tubes. Which are great, d3a are high gain low noise, so our riv gets to be small.

@Tesla Audio no, lundahl sounds horrible.
These ones: https://www.diyaudio.com/community/threads/output-transformers-for-dacs.327794/
 
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@m17xr2b this is not just an addiction. It is obsession....🤣 Really nice work there.
Just a question, what do you mean by ' dac output is 7.5KΩ' ?

Since I'm using a 12Ω IV resistor with 1:25 transformer and the impedance is the ratio squared, that's 12 * 25 * 25 = 7500Ω output impedance. Following the usual 1:10 impedance radio for good signal transfer that means at least 75KΩ input impedance for the next stage while also driving the miller capacitance to avoid high frequency attenuation.

Another question if you don't mind... what are these?
View attachment 1213309

Those are the actual IV resistors, indeed Path Audio.

The IV transformers I'm using are actually parafeed output transformers used in reverse, Magnequest EXO-45, already had them from other projects and historically one of my favorites. I didn't expect them to work as well as they do but they're at the top of the pack over sowters and audio notes. Lundahl is excellent for high current chokes, less so in the crucial signal path IMO.
 
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Another PCM63 DAC lives! DIR9001 into miro1360 pcm and Lundahl output stage, with Sparkos PSU

Ran into one issue with setup and I'm looking for feedback. Is 24bit I2S a requirement? My initial test
resulted in no low bass with a 16bit SPDIF signal. Setting output to 24bit via SMSL PO100 from my PC
finally resulted in a full audio bandwidth. I see most people are using I2SoverUSB or something similar.
Do I need a different SPDIF to I2S board that supports 16bit I2S? I'd like to use my high quality 16/44
CD transport if possible. Thanks!
I have zero experience with SMSL PO100 and hard to say how the resulting output from SPDIF looks like. I guess it will be best to leave it at 24 bit and playing 16 bit recordings should work automatically 🤔
SPDIF to I2S based on DIR9001 must work fine - if the configuration is correct = 24-bit, MSB-first, I2S (check this website: http://www.pavouk.org/hw/modulardac/en_dir9001spdif.html )
Note that these devices can be configured for higher bits and they still be able to play lower bit recordings automatically 🙂
 
I have zero experience with SMSL PO100 and hard to say how the resulting output from SPDIF looks like. I guess it will be best to leave it at 24 bit and playing 16 bit recordings should work automatically 🤔
SPDIF to I2S based on DIR9001 must work fine - if the configuration is correct = 24-bit, MSB-first, I2S (check this website: http://www.pavouk.org/hw/modulardac/en_dir9001spdif.html )
Note that these devices can be configured for higher bits and they still be able to play lower bit recordings automatically 🙂
Thanks! It happens with a SPDIF signal from my transport also. It is working great and sounds awesome from my PC, any bit rate recording plays fine with the PO100 set to 24 bit. My DIR9001 looks to be a copy of that link. Config is set to correctly to the only I2S setting on it, but it's like the bits are aligned wrong with a 16 bit source. I didn't see anything that jumped out in the datasheet for the DIR9001, but I think I'll order your SPDIF to I2S board and see where that goes 🙂
 
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