Here are my thoughts on the Atom Dac after a few weeks of owning it.
I have to say that the original Atom Amp plastic build was a bit of a turn-off, but it was mainly because of the small plastic volume knob and the fact that the unit was too light and would move when adjusting the volume. I would suggest JDS simply install a deeper volume knob with some texture to improve traction and put additional weights in the amp by default.
In respect of the Atom DAC though, I have absolutely no objection about the plastic casing. In fact, out of all the DACs that I have owned, which includes the Topping D50s, D70B, Schiit Modi 3 and Bifrost 2, the Atom DAC has been the most RFI-resistant of them all. I live very close to a commercial airport as well as a military radar site, and a lot of my equipment picks up a specific radar blip, which the Atom DAC completely rejects. So, proper engineering triumphs over brute force and metal shielding.
Moreover, the Atom DAC is set-and-forget type of deal as it does not have any buttons, so it does not matter whether the casing is light or heavy.
I do think that there is a bit of unfair bias against plastic casework in this hobby - can you imagine video gamers insisting that the PS5 had a metal case?
I actually have nothing against high quality textured plastic because I find it to be more scratch resistant than brushed aluminum cases and does not dent or mark as easily. Plus, the finish tends to be very uniform under all kinds of lighting.
In terms of the sound, it is simply fantastic, clear and transparent. The noise floor is extremely low and there is not even a hint of EMI or RFI even at extreme volume settings. Channel balance (measured with my multimeter) is within 0.03dB, which is great. No weird glitches to report in terms of having to restart the unit over the last two weeks. My D70 would lock up at least once a month when streaming Tidal, having to restart the unit.
The short USB cable provided is great quality as well with an installed ferrite bead to further reduce interference. Usually I discard the provided accessories because they are garbage quality, but not in this case.
JDS customer support is legendary and they are willing to customize the firmware of the unit for specific customer needs - for example, if the PS5 and the XBOX X end up only supporting the UAC1 protocol, JDS has provided a firmware that would enable us to downgrade from UAC2 to UAC1, although it is a one-way upgrade (there is no way to go back to the UAC2).
The only suggestion for improvement that I have would be to turn down the intensity of the LED ring by 50% as I generally prefer very subtle signal LEDs. Nothing that a Light Dim cannot fix though. JDS actually offered to install a resistor in front of this LED before shipping the unit to me to reduce the light intensity for no extra charge, so it is worth asking them.
It certainly is not the cheapest possible DAC, and it does not have the most features, but it does what it does flawlessly. It's a case of substance over style and understatement over flash. After a few years in this hobby, these are the qualities that I have come to appreciate.