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Beware of SACD Transports -- they probably will not work with your favorite DAC

Hello, I just learned a painful lesson. I'm guessing that not many people will know this so I'm going to put it in here.

The audio on a SACD is encrypted.
If I were to purchase a SACD / CD player I have nothing to worry about. The Audio is un-encrypted inside the player.
However if I were to purchase a SACD / CD Transport made my brand Z, I would have to purchase a brand Z DAC???
Apparently Sony who owns the SACD format mandated that the audio on the SACD itself is encrypted and
the digital output from a SACD transport is ALSO encrypted. It looks like the actual un-encryption is done in the DAC.
There is no standard for doing the un-encryption so every manufacturer has their own proprietary way of doing this.
So I cant use a Esoteric SACD transport and an Auralic DAC which is what I tried to do?
londontk
stevecham
3,298 posts
 
So much misinformation out there:

PS Audio did not invent/innovate I2S. That has existed all along in the Sony Philips Digital Interface (SPDIF). PS Audio simply chose to walk upstream and access the multiple data streams coming out of the transport before it was combined into a single data stream for the DAC. I2S is the standard protocol, PS Audio chose to use it with their players and DACs.

See Paul McGowan’s explanation:

https://www.psaudio.com/askpaul/what-in-the-world-is-i2s/


morningstaraudio's avatar
morningstaraudio
78 posts
 
This is why a Marantz SA-10 is in my near future.
gerryah930's avatar
Ag insider logo xs@2x
gerryah930
51 posts
 
Most high-end audiophile brands, including dCS, EMM Labs, MSB Technologies and Esoteric, provide a proprietary, brand-specific optical link from their own transports (and their CD players which can serve as a transport as well, providing a direct optical link bypassing any built-in DAC or upsampler) to their own DACs, just like PS Audio. The real question should be - is it possible to re-engineer this optical link, allowing transports from one brand to link to the DAC from another brand. The answer is yes, but I am not going to explain how to do it. 
rwwear
2,692 posts
 
Here's an inexpensive way to get DSD playback through a DAC.
https://www.ebay.com/itm/Singxer-SU-1-XU208-XMOS-USB-Digital-interface-DSD256-PCM-384kHz-I2S-HDMI-output/263653745722?hash=item3d62fce43a:g:MqoAAOSw6n5Xv913
FAQ: What is DoP (DSD over PCM)?

The original idea for DoP was invented by dCS in 2011. It involves taking groups of 16 adjacent 1-bit samples from a DSD stream and packing them into the lower 16 bits of a 24/176.4 data stream. Data from the other channel of the stereo pair is packed the same way. A specific marker code in the top 8 bits identifies the data stream as DoP, rather than PCM. The resulting DoP stream can be transmitted through existing 24/192-capable USB, AES, Dual AES or SPDIF interfaces to a DoP-compatible DAC, which reassembles the original stereo DSD data stream COMPLETELY UNCHANGED.

If something goes wrong and the data stream is decoded as PCM, the output will be low-level noise with faint music in the back ground, so it fails safely. This can happen if the computer erases the marker code by applying a volume adjustment.
toddrhodes
48 posts
 
Maybe a bit of a sidetrack but this isn't surprising - the transports + DACs I've tried can't even do pre-emphasis correctly, so expecting DSD to work is a real long shot. Some really good info and solutions in here though. I would like to be able to try i2s again at some point but what I'm getting out of just 75 ohm BNC is more than satisfactory for the moment. 
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