Went ahead and final got an EITR after wanting it for a while since my STAX SR-L300LEs finally came in a week ago. Also ordered a Benchmark RCA to BNC cable to go from EITR output to the Gustard X20U BNC input (already have RCA and optical inputs being used by my OPPO Blu-ray player and XBox One respectively). EITR came in yesterday and the Benchmark RCA - BNC cable today. Connected it via RCA-RCA last night to test it out. Setup is STAX SR-L300LE <- Mjolnir Audio SRD-7 energizer <- NAD C275BEE stereo amp <- Schiit Loki <- Gustard X20U DAC <- Schiit EITR <- Windows 10 laptop w Foobar2K and FLAC files. I do hear an improvement in sound.
This track is one I knew I wanted to first use to try and help understand the difference:
The 3:15 on short span with all the cymbal work... was more of a 'choppy digital crashing' sound with the Gustard USB input. Sound with EITR is more detailed and finnessed with a better sense of them actually being cymbals. Overall as well, there seems to be a little more of a sense/presence of the room - there is a little more feel/definition to the recording/performance space it seems. That's about all right now I can tell.
Also listened to this song, as the 24bit, 44.1kHz, 1556Kbps download has very nice micro detail throughout, and the album as a whole impresses with it's detail and clarity/dynamics:
Seems a slight edge has been taken off and the details and everything just seems smoother/less harsh... but still as detailed as ever, or even very slightly more.
I do think I'll be keeping the EITR in my setup...it seems to perform like everyone has said...not HUGE differences, but seemingly noticeable differences.
P.S. I don't like the white LEDs Schiit uses...a cutting mat, 6 layers of Kapton tape, 1/8" precision hole punch, and a ball peen hammer works wonders to fix it...