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Quad PCM58 current-out SE/balanced board

You are right Richard.
These IR LEDs are a pain. They are really small (0603 size) and worse, the orientation mark is only at the bottom side.
But this is the fun of diying 😎

And here is the IR glow from the Dark LED module
George
 

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My Quad PCM58 DAC + Dark LED I/V first audition after the assembly.
The DAC was with zero hours.
High mids and treble were almost missing.
After two hours with music, they came to the surface.
It needed some twenty hours playing music for sound to set.
Big sound, very good low end. Well balanced mids and pleasant highs.
I see that sound still settles more from day to day.

I took some FR measurements. Input was SPDIF,
E-MU 0404 sound card. SPDIF out (so Sampling Rate was up to 96kHz), to analog in
Two measurements at each SR. One unfiltered (9th order filter of the DarkLED bypassed) and one filtered (9th order filter of the DarkLED installed).
Quad PCM58 DAC in SE configuration
DarkLED output load: 20kOhm

George
 

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Reactions: abraxalito
Step level measurements.
1kHz signal. -130dBFS to 0dBFS
E-MU 0404 sound card. SPDIF out, to analog in.
SR 44.1kHz

I find linearity to be excellent. - 0.5dB at 15bit depth, +0.5dB at 17bit depth.
Distortion profile is very close to Abraxalitos TDA1387 DACs.
All these with no trimmer installed yet.
George
 

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To jump on the recommendations of the others, I have Richards 4 x PCM58 dac in balanced mode (8 x PCM58) and it is exquisite. Im enjoying it more than my previous best reference dac the Bricasti M21 (€18k RRP at the time, I bought it used). The PCM58 dac renders music with more emotion and beauty than the M21, without any obvious short falls, except convenience; M21 had every type of connection including ethernet for internal streaming, which I miss but can be jimmy'ed up with other boards/sources.
I did find a more powerful power transformer to be beneficial to sonics(40 VAC toroidy). I have never heard a single PCM58 per channel setup so could not comment on how much better 4 per side makes, I do trust Richards knowledge and the data that supports lower SNR etc. No component changes have been made but perhaps experiments will be made in the future.
Highly recommend this dac, thanks Rickard.