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

You confirmed what I told in the past 🤣 "do not buy the SMD versions of the PCM1702 and PCM1704 from china, because it is desoldered from e-waste and is damaged by heat, they use a heatgun without temperature control" ... DIP chips are a little more prone to damage, and some could be pulled out from the socket without damage 😉
There are also those used-unsoldered, but these SMD PCM1702 I bought were not unsoldered ones, but brand new (at least in appearance). In both cases, the same chip is inside, it just heats up and draws current from the -5V analog supply.

The first pair had a sanded surface and stamped new markings (I found this out when I got the second pair 🤣 ), the second one looked like the original but all of them didn't work. In the first case, the ebay seller gave a refund himself. In the second case, the seller didn't want to, but I got a refund from Aliexpress. So what you said, don't buy SMD PCM1702, applies to any, new or used.

Of course, both sellers continued to sell that garbage, regardless of the negative reviews. 🙄

And these DIP16 that I bought from Polida are also new (NOS). I took a good look with a magnifying glass, there are no signs of previous use. They work with an adapter PCM1702/63 anyway, that's enough for me. 😎
 
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So from the same guy Polida :

PCM1704-K costs 180USD
PCM1704-J costs 188USD

PCM56-K cost 18.44USD/5pcs, or 3.69USD/pce
PCM56-J cost 43.04USD/10pcs, or 4.30USD/pce

Lower distortion for less money.
Isn't that a bit strange ? 🙂
(Maybe distortion sounds better ?)

PS
PCM56 -K cost 18.66USD at Rochester.
Only 1pce left, but guaranteed 100% genuine and unused.


Patrick
 
About those prices and their illogicality, it's nothing unusual, I've seen it before. I guess it depends on the purchase price or who knows what those sellers are calculating.
PCM1702-K from ebay seller Polida, they work, and it is written KOREA on them. The price is $31.50 a piece and postage is $2. If PCM1702 is already taken at the start, then it is better to make a Miro PCB for 1702 than to use the one for PCM63 with the 1702/63 adapter
PCM56P-K from Polida look very similar to PCM1702-K, except it is written JAPAN.
I don't know if they are original, just like I don't know about these PCM1702-K. 🤣
I think they are cheap enough to try (PCM56). I'm waiting for a friend to bring me some used AD1856, if that doesn't work I'll get a PCM56 from Polida.
 

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I don’t know what is now, but 5-10 years ago the word “Polida” was synonymous with the word “fake”.
It's good if things have changed.
I heard about some fakes from Polida long ago. Maybe they sell a mix of original and fake stuff, who knows. And this PCM1702, maybe it's an original but plain one without a mark, and someone added a K mark to sell it more expensive. I will use it for rehearsals, not to risk with PCM63 originals. And if it sounds better than PCM63 (I doubt it), it will stay permanently. In that case I will make a PCB for the PCM1702.

I currently have fully packaged Miro PCBs for the PCM63 and AD1865, and blank PCB for the PCM56 with all parts except the PCM56. I just don't have time to assemble the power supply to try it all out.
 
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Since we are talking about other R2Rs than AD1862.

I was wondering why AD1860 does not get more attention,
It is pin compatible with PCM56, among others.
18-bit, 5V or 12V operation.
K-grade has the same distortion spec as AD1862N.
J-grade typically same as K-grade only slightly wider tolerance.
And AD1860R-J is a real bargain at 8.25 USD a piece.
Can also order through DK.

If you stack 2 of those, on SOIC to DIP adaptors, you might lower the distortion by 3dB.
Even beats the AD1862-J then.

But maybe miro knows something I don't ?

🙂


Patrick
 
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