I had an old Fostex DMT-8VL years and years ago and i still remember liking the sound of it. Then again it was all I knew (aside from 4 track tapes) at the time. Compared to the
ASR-X I had concurrently, I remember it as less beefy/sparkly and more grainy/punchy.
What audio interface are you using (it may be the problem...)? Assuming it has a SPDIF (or AES or ADAT) input, perhaps look into older ADCs like the Symetrix 620 or some other 18/20 bit converter box from the mid 90s.