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

I could use some help. Cant seem to get any sound from Dac 1 side. I have switched the dac chips and it made no difference. I switched the opamps from the working side to the non working side and no difference. I appear to get the same voltages at the same pins on the dac chip and the op amp chip for the working side and non working side. I am using Miros SPDIF to IS2 convertor. I am feeding it from a coaxial source if that matters. Can someone also explain the jumpers on the convertor? What is 24 bit LJ and 16 bit RJ. I get the IS2 settings I think.

Thank you for looking.
 

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@gsrchrisu use a good contact cleaner and a brush to clean the spaces between pins of logic gates particularly the following:
IC1 pin 13,14.
IC2 Pin 13-14
IC3 pin 8-14
IC6 Pin 1-2.

If I remember right miro1360 did reply a post of the same nature earlier in the thread and check voltages across certain pins, but just to be on the safe side please do clean the spaces between pins of logic gates the ones mentioned above.
 
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Update: I found 3 pins on 2 different shift registers not making contact, I love the challenge of smd parts but what a bugger when they dont work. I went over both sides with a toothbrush and cleaner. Now both channels are singing. Thanks for looking. Off to try to get my PCM63 version that has no sound output from either channel. But now that I have known working parts will make debugging much easier.
 
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ra7

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Hi everyone, I have been trying to get the AD844 to work as a drop-in on the TDA1541 board but can’t seem to get it work. As a drop-in, it is bass light. I presume the input offset trim is causing the early roll off. Have folks been able to work it in without a dedicated separate PCB? I read about the 844 plus buffer board somewhere but hoping to try it out before jumping to that.
 
Hi, I am dealing with noise issue. When no audio is playing, the speakers are completely silent. When I start to play audio files (does not matter if it is youtube or TIDAL), there is a white noise present. The noise is audible even at the distance APPROX 1 meter from speakers. In previous posts, there was a simmilar issue caused by a GND PIN from I2S- not my case. With my previous PCB, I got the simmilar problem but only on one channel. There was present not only noise but distortion as well. Does anyone have some auggestion what might be the case of this issue? Many thanks in advance.
 
Hi everyone, I have been trying to get the AD844 to work as a drop-in on the TDA1541 board but can’t seem to get it work. As a drop-in, it is bass light. I presume the input offset trim is causing the early roll off. Have folks been able to work it in without a dedicated separate PCB? I read about the 844 plus buffer board somewhere but hoping to try it out before jumping to that.
Can you describe what changes you made to the circuit to take the AD844?
 

ra7

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Joined 2009
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As I said, doing nothing and just dropping it in results in rolled off bass.

I read the spec sheet and have read some the threads, mainly this one:
https://www.diyaudio.com/community/threads/using-the-ad844-as-an-i-v.227677/

The spec sheet example doesn’t talk about offset nulling but it is needed. It has to be a high impedance node that connects to the input of AD844. So, we need to change the 3k3-5k6 and trimpot network to get there. See George’s example in post 5 of the thread above. Space is tight so I’m wondering if anyone has done this already.
 
Hello friends, for my next project I'd like to realize a r2r dac, with tubes output stage. This thread looks really what I'm looking for, yet it's gonna be difficult to go over 412 pages...

Is there perhaps a bom, or a thread with the last mods, such as #2031 for catherine dac? I like much what the user Nautibuoy did in his post #8217, but still going to read 400+ pages is a challenge... So far I understand that boards can be bought from Miro or done directly with the Gerbers, any quick hints for the rest?
Thank you!
 
@Michelag catherine dac is not working as expected (headphone part is not good) and this project I classify it as a failed prototype and that is why it is not shared, but the future can bring a working one :ROFLMAO:
... follow @Brijac words ;)
Boards can't be bought from Miro :ROFLMAO: Everything is "free" - gerbers (material for production) are shared and you can put these gerbers into any PCB manufactory for production - and this is perhaps the cheapest part from DAC.
 
So pumped finally got my PCM63 dac to make music. Thank you to Vunce for the 811 I/V and thank you again to Miro1360 for the Dac gerbers, was really fun to build and sounds amazing. Alot of learning happened with all the challenges these projects presented. My best tip is to use your DMM and beep out the pins on the SMD logic and opamp parts.
 

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In case of having some trouble with noise, do not use cheap USB sockets from aliexpress. I tried not to make any compromises, but only cheap component which I used was a USB socket. I thought it should not make any difference. But it did. Just letting you know, if someone will deal with a similar issue, do not use cheap USB sockets :)
 
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So pumped finally got my PCM63 dac to make music. Thank you to Vunce for the 811 I/V and thank you again to Miro1360 for the Dac gerbers, was really fun to build and sounds amazing. Alot of learning happened with all the challenges these projects presented. My best tip is to use your DMM and beep out the pins on the SMD logic and opamp parts.
some advice about AD811 (after all, I am the author of Vunce's I/V ); remove that PCB as far as possible from the transformer and reduce the length of the cable between the miro PCB and Vunce PCB ( PCM63 to AD811).
 
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