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

Boxed up. Time to actually listen.

😎



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LME49710. The crown jewel of the Bob Pease era at Linear. As the intent is to also have transformers for balanced out, I figure an audio-specific opamp that can giggle when looking into 600ohm load is a reasonable idea. I’ve also had those in my collection looking for a project for quite some time, and this is perfect.

There’s a couple of housekeeping items still to do, diode snubbers being high on the list, but I’ll keep it like this for a while and see what it sounds like. Initial impressions are wonderful.

Also @Vunce I have to give an official thank you as this particular PCB was in the set you sent. Wouldn’t have gone this direction without your help, it’s very appreciated.

@zoom777 Honestly I have no idea which is powered by what… the jumpers are as shown here R13 open, SJ3 closed.

https://www.diyaudio.com/community/attachments/img_2997-jpeg.1247224/

View attachment 1247224

As for changing any configuration, no, I won’t change anything on this build aside adding output transformers and diode snubbers. This one is intended to be the paint-by-numbers control to compare other variations with.
 
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Hi guys. Can I ask for some help please?

So today after a long time of no Miro DAC in my system I put it back in. It's a Ian Canada /RPI front end. The dac that was there was one of Richard's excellent little dacs.

So all I did was swap the dac and PSU dac out, now in there is my long term tested PSU1 and Miro 1862. Obviously had to switch the i2s and outputs.

All I can get out is LOUD highly distorted music. Even with the digital volume down and the preamp knob on 1 click, I get pretty loud distorted music.

The Miro 1862 has the same PSU, transformer as in the other chassis. It is just getting a different i2s source. (from Ian's fifo.) I've double checked the i2s as I'm aware the labelling is slightly different between the dac and the fifo but think I'm all good there.
Have turned off any oversampling in the Rpi so I'd getting the native sample rate. Clock lock lights illuminated so that's working. Checked opamp orientation.(1611)

Anyone had anything similar or what to check please?!
Hi Jim, it can be wrong configuration, or data pins swapped, or incorrect pins used, maybe missing GND (on some of my DACs data pin 8 (gnd) is disconnected and it has caused so many problems so far 😀 😀 😀) ... I mentioned it on the website: https://electrodac.blogspot.com/p/dac-ad1862-almost-tht-i2s-input-nos-r.html (search pin 8).
... It would be best if you have the simplest USB/I2S device close at hand and test it for basic functionality:
https://www.aliexpress.com/item/4000282012228.html ... for 6€ with shipping you can not have better test toy at home 😀
 
Thanks Miro. I had another look today but still same. I'm using u.fl but will maybe try plain cables. I don't have pins 7 and 8. Think I'm using rev1.3ppy.

Last time I used the Miro DAC was with a EUVL external IV. I never removed any IV components from the dac apart from op amps. I tried it today without opamps but got no sound at all. I would have thought it would have had a path via the IV resistor..?!

Have a very merry Christmas and I'll hopefully try some tests after the next couple days.
And thanks for that link!👍🏻
 
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