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

Hey guys,
have you tried Sparkos or Muses02 oamps with the DAC?
Did you hear any improvements?
Does it worth to upgrade to one of these regarding the price?
Sparkos SS3601(single) or 3602(dual) and Burson V5 or V6 Vivid sound very similar, it's hard to tell the difference. I haven't found a factory OPA to sound that good. The Burson V6 Classic has a slightly warmer sound and a different spatial presentation, perhaps a little less detail. I haven't tried Muses, I'm happy with Sparkos/Burson.
 
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Something for those interested in PCM1702. Denon used a L-grade version of PCM1702 in many of their mid-level CD-players. Datasheet does not mention L-grade and there seems to be confusing information in some web-sites. Some believe L-grade to be a lower grade as in PCM56 while some believe it is higher grade. As I have an old Denon CD player not in use I decided to pull out the PCM1702 L chips and try them out in my PMD100+PCM1702 dac.

Here is a measurement of PCM1702L at 0dBFS (IV+LPF is OPA1612). Both my L grade chips measure about -98dB THD+N which is similar to K grade.
 

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Gradings are basically there to tell you that there was more quality assurance/slower precise manufacturing. You can get J chip that performs better than K if you're lucky. Look at it this way, if you drive faster to your destination, you will reach there faster but there are many more accidents in the process. And if you drive slower, you will reach destination slower but there wont be nearly as much accidents on the way there. Same with manufacturing and grading in these chips. Btw there should have been a batch in pcm1702 series that would be equivalent to Y grade pcm63p for yamaha, and it has been requested by denon but they wouldn't spring for quantity and price.
 
About half a year ago, I bought 5 pcs of PCM1702 dip from ebay at a good price, now they play in my DAC. 6 pcs in total, two were from before and one was left as a reserve.
Recently, they appeared again, but now for 2 pieces but also at a higher price, unfortunately the package got lost in transport and I got my money back. Today I found an ad for two Denon dcd655's at good price so they will serve as donors. So I will finally have 8 pcs PCM1702 in my DAC. :)
 

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So, my Miro's DAC with AD8162 is almost ready. I use PCB for stacked I2SoverUSB not-flipped. It's now playing, but I've noticed a strange problem and I'm wondering where to look for the cause. There is mixing of the sound between the two channels - if something should only be heard in one channel, it is heard in both. I use I2SoverUSB configured correctly personally by Lyuben. I personally assembled the DAC and I tend to look for the reason there. With another DAC, I'm testing the rest of the system and it's working as expected. I would appreciate any ideas...

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Insert jumper at J14 and short SJ3.

Why are the opamp sockets elevated from the board? This could possibly cause oscillation, especially with LM6171. Opamp sockets should mount directly on the pcb. Mount the surrounding components under the pcb to gain access to the opamp sockets.
 

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Insert jumper at J14 and short SJ3.

Why are the opamp sockets elevated from the board? This could possibly cause oscillation, especially with LM6171. Opamp sockets should mount directly on the pcb. Mount the surrounding components under the pcb to gain access to the opamp sockets.
Thanks Vunce,
I have powered the I2SoverUSB board independently with two separate power supplies for the usb and isolated part. Therefore, J14 and SJ3 are open. As it plays normally I will consider moving items down.
 
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Powering the JLS board with independent supplies will be my next move also. (y)
I will never understand why the JLS board was made so small. It should be bigger and more expensive - it doesn't matter what the price is - I would pay. Because there are even better, bigger and stronger similar devices which have Xilinx Spartan with - Highest I/O per Logic Cell - plus bigger and more precise oscillators.
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@ernesternest easyDAC is experimental toy and is asking for some improvements :giggle: ... the mine is yet working and the only problem was in a broken MLCC capacitor (the reason why I don't like these SMD capacitors, very fragile).
Where did you buy the AD1862 chips?

The improvements you can try with easyDAC:
  • create Y-cable for double power (you can DIY it or maybe buy one) ... very simple, the second USB is without +D -D and uses only +5V and GND (paralleled with the first USB cable)
  • add filtration capacitor near the DAC chips (electrolytic UFG ... C5, C11, C27, C35) ... carefully with the polarity
  • change tantalum capacitor which is near the DAC chip for electrolytic UFG (C12, C36, C20, C40) ... carefully with the polarity
 

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