To more thoroughly grok what Bricasti is doing with DSD, it's worth noting the manual for the M3 (the Bricasti guys are engineers, not writers...emphasis mine):
"...DSD playback and the M3
"DSD playback with the M3 is done via DoP when using the AES or SPDIF inputs, and Native or DoP for USB. DoP is DSD over PCM and for DSD 64 is the 1 data bit stream embedded in a 176.4k 16 bit PCM data stream with the extra 8 bits out of the 24 bits used for identifying that it is DSD not PCM. This is true DSD and not PCM conversion. When using a computer audio setup and USB, the media player can be set to send out the DSD as native or DoP but only native will function for DSD 256 rates.
"The M3 features 2 digital audio conversion paths, 1 for PCM which utilizes a sigma delta type, and <one> for DSD <which> is a true one bit modulator of our own design and unique to the industry. This DSD conversion is a true 1 bit analog converter followed by an analog post noise filter. The result is a true a pure DSD playback unlike any other converter in the market. It is recommended that this feature be selected in the status menu labeled NDSD, setting to DSD PCM will use the ADI 1955 as the multi-bit converter which will impart a different sound character.
"To use it all you need is DFF or DSF files, the M3 can accept them as DoP and Native data streams to play them with any input. When DSD is received for playback the status and filter displays will read DSD, and when it next plays a PCM file it will revert to your last used PCM filter and display will update accordingly. Playback is seamless as any other PCM sample rate change. If the M3 does not display DSD when playing back DSD source then check your media player settings for DSD and insure that it is being sent as DoP if using the AES or native if attempting to play DSD256 with USB. When using USB and the LAN the M3 supports DSD 64, one bit at 64 times 44.1k sample rate, and DSD 128 or double that rate and DSD 256. DSD 64 is the SACD standard and 99% of all content is released and mastered at this rate. When selecting NDSD DSD setting, the DSD post noise filtering is done in the analog domain so there are no DSD filter settings. An artifact of DSD processing is the buildup of ultrasonic noise and with DSD 64; this noise starts at 24 kHz and rises to peak level at -50 dB at 50k and beyond. In the M3 set to NDSD DSD this filter is implemented with a simple low order low pass analog filter for the very best sonic performance."
After many DAC trials, face-offs, etc. over the past 10 years, I too decided to move both of my systems up from mhdt Pagoda Balanced R2R DACs to Bricasti -- M21 on the primary system and an M1LE Gold in the secondary system. The M21 has three paths: 1/ PCM via the AD1955 chipset, 2/ R2R ladder DAC, 3, Native DSD in analog. I have to get organized to try the DSD in analog. On streaming from 6000 ripped CDs, from Qobuz and Tidal HiFi, I listen 80% of the time via R2R on this DAC, 20% Sigma-Delta. For Bricasti skeptics, I'll note that Ron Resnick, a perennial digital doubter, was at my house yesterday to listen to my system with the new Absolare Altius 845 PSET amps. At his request we listened primarily to vinyl but when I streamed some same-cuts from Qobuz in R2R through the Bricasti M21, Ron's reaction was "...I have to admit this is very, very good..." Not that he still doesn't prefer vinyl though. The Bricasti has made me closer to neutral on the enjoyment and engagement scale in the question of vinyl v. digital instead of analog-biased. The M1LE Gold is Sigma-Delta only and has 15 filters. The M3 is derived from the essential design of the M1, but is not dual-mono, and includes just two filter choices, one minimum phase, one linear. On my M1LE Gold SE with 15 filters, I use one minimum phase most of the time and one linear, occasionally. The Bricasti M3 and M1 variants are the most analog-like (or R2R-like) Sigma-Delta-only DACs I've heard.
I have a Holo Spring v3 KTE in for evaluation for someone else. Holo asked me to give it 500 hours of burn-in before evaluating. I'll start that burn time later this week.
Note, my Bricasti M21 is fed by an Auralic Aries G2.1 streamer, and the M1LE Gold by an Auralic Aries G1 streamer.
Phil