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

Experiment with one of your speaker and your room about measuring then filtering, maybe first with EQ (for instance from the player of a RaspBerry Pi to understand first about power response, i.e. the spl curve of the loudspeaker its peaks, holes, what frequencies involve your ears... so buy a mic and spend time into free measurement soft always talked in numerous forums.

About the list of the oaps, my oap list that worth it also involve AD810, Vunce opa810 board Rogic inspiration, opa1646, opa 1611 (difficult), opa1655 (difficult)... AD797 seems to have its fans and is a good trade off too. (RTFT)
You mean for room correction?
 
No, Just to understand you surely do not need a tweeter but optimisation and where it is needed in spite of following a Be fame...
Ок, I got it! My friend have a microphone and soft. I ask him.

By the way - I did manage to compare Dodson 217mk2d and Miro Dac (although not quite right - Dac was connected in that day). Me and my friend was listened both devices on same tracks. He says that content winner is 1862 and by the sound the best was Dodson. The last one have a much resolution, colors and dynamics. Miro Dac have a more neutral, studio sound but also was really good. Perhaps with burn in period he also will gain the resolution and colors. I'll see soon!
 
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...also all of this has also to see with the oap choice and all the decoupling caps and PS combo. I think all the mirodac sounds different because the choice versatility at building it and of course about each owner hifi around. That's why I do not review too much my dac confs btw.
 
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@sworder84 Definitely play with different OpAmps. For more colored sound try OPA134 ;)
Dodson 214 mk2-d uses PCM1704 as DAC. Can you check and tell us what are the OpAmps in this device? Especially the one OpAmp next to the PCM1704 chip.
 

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@sworder84 Definitely play with different OpAmps. For more colored sound try OPA134 ;)
Dodson 214 mk2-d uses PCM1704 as DAC. Can you check and tell us what are the OpAmps in this device? Especially the one OpAmp next to the PCM1704 chip.
Sorry Miro, no. I was already returned the device to his owner. He asked me do not open the device. I was visiting at last year and we together listening Wadia 15 and this 217mk2. 217 was definitely better. Acoustic - B&W 802.
 
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@intojazz There should be no scratchy noise. Can you try different opamp? (something in the DIP case) :)
Try it on headphones directly.
Hello Miro,
Finally got around to replacing the lm6171 opamps. I soldered up some 797 brz and am just now listening. The scratching issue is gone. I will continue listening and update with an impression. Initially the sound stage is improved and very much like the lm 6171. It seems odd that the 6171’s were creating this issue. I’m a bit disappointed with those as I’ve not really had a chance to evaluate them.
Well thanks for your help, it is very much appreciated
 
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Yes it’s possible. When ordered a dip package lm6171 was not available. So I used soic with an adapter which does put the opamp almost 1/2” above the pcb. I couldn’t find anything that was closer. I saw a post that talked specifically about that but turned out was not an issue. But I’m not sure that configuration and mine were exactly the same.
At this point the 797 opamps haven’t shown similar issues. I do have an order for some lm6171 in dip package along with the correct socket. I will try them but overall distance from pcb doesn’t look like it will be that much different
We’ll see.
Thanks
 
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Yes it’s possible. When ordered a dip package lm6171 was not available. So I used soic with an adapter which does put the opamp almost 1/2” above the pcb. I couldn’t find anything that was closer. I saw a post that talked specifically about that but turned out was not an issue. But I’m not sure that configuration and mine were exactly the same.
At this point the 797 opamps haven’t shown similar issues. I do have an order for some lm6171 in dip package along with the correct socket. I will try them but overall distance from pcb doesn’t look like it will be that much different
We’ll see.
Thanks
Well it seems the scratch has returned. So perhaps the soic package is not ideal. That’s not to say it couldn’t be something else entirely. I will continue searching.
 
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Looking at your work here https://www.diyaudio.com/community/...st-tht-i2s-input-nos-r-2r.354078/post-6992778 all seem very clean.

Some ideas meanwhile the dip8 arrival :

Check the JLsounds I2S set up at its the bottom as per what has been explained in the thread.
The traffo seems far enough but try to put a tin above to reassure you about coupled field.
Does the streamer does not upsample all your material, check if the same clicks occur at different sampling speeds : 44khz to 388khz.
Check also with magnyfing glass around the registers and their caps if it is clean. Idem around the jlsounds and the dac pcb...
Certainly the oaps but who knows, it costs nothing to check.
 
Hi guys!
I bought the Nichicon (UKW1E101MED, Aluminium Electrolytic Capacitors - Radial Leaded 25volts 100uF 20%) caps for C17, C18, ...
It seems that the caps have to be bigger (see my DAC plate pic).
Did I buy the wrong caps? Or can I use it?
Thanks!
View attachment 1045808

View attachment 1045809
C17 and 18 have -12V/+12V on them and your caps are rated 25V. You can use caps that rated beyond the operating voltage but not below.
 
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