Allo Digione Signature + LPS vs. Berkeley Alpha USB to SPDIF Converter?

I'm going to answer my own question in case anyone else finds themselves in this situation.  The Alpha USB is better and it's not close.  I can see why people rave about it.  Just more natural and refined, more 3D and more inner detail.  It combines the best traits of the Audiophilleo + PurePower, Wavelength Wavelink, Weiss INT202, and Empirical OffRamp 5.  Fantastic.

The Digione Signature performs very well at its price point.  VERY clean sounding, but not harsh.  But, it produces unnatural leading edge definition to my ears and soundstage is a bit flat.  In one of my two systems it also produced a peculiar inverse fisheye/concave perspective where performers to the sides of the stage are a bit forward while middle performers are recessed.

Also, I found that the Shanti linear power supply brings a significant improvement to the Raspberry Pi 3B+ USB output so I kept that combo to replace my venerable Mac Mini.

I also preferred my Audiophilleo + PurePower to the Allo Digione Sig.  Again, more natural and refined sounds and soundstage.

You prefer SPDIF to USB on the AMR?

Interesting thread. Thank you for your impressions.

But I would have the same question. The conventional wisdom is that on a DAC of your quality, the USB input outperforms the spdif.

But one never knows in audio. On the advice of someone I respect I recently found a 1M $7,99 toslink cable to outperform a $130 spdif one. But I am eventually looking for a USB solution. In any event, a renderer that gets the music files completely out of the computer.

Until I can find an I2S one.

Yes, I do prefer SPDIF to USB. This DAC has tube SPDIF inputs and, while USB still sounds very good, SPDIF brings a bigger, wider, more open, vivid sound. Aside from the size aspect, music through the USB input sounds like the performers are just kind of going through the motions, like another day on the job, while SPDIF sounds like they are really putting their hearts into it. The caveat is that it depends on what you feed it. When you introduce a converter, its power cable/supply, and a SPDIF cable, that all tunes the sound.

In some applications I have preferred toslink with a good glass cable too. My experience with direct USB hasn’t been too favorable, but I’ve read that much progress has been made in recent years. It was generally not very good in the early days, even with advent of asynchronous interfaces. Actually, I did have an iFi Pro IDSD and found its USB input to be comparable to SPDIF, if not slightly better. However, I thought wireless streaming was best. Go figure.

As always, YMMV with system synergy and personal taste.