PWT via coax output

I’d go so far as to say, based only on my own personal experience, that the vast majority of SACDs released these days are hybrid. My collection contains only a very small handful of non-hybrid/single-layer-SACD-only discs, and they were from long ago, issued when the medium was still relatively new.

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Okay just to reinforce my understanding. If the PST is connected i2s to a non-DSD DAC it will play the redbook layer of a hybrid SACD, for non-hybrids it will play silence since it does not downsample the DSD layer?

Ity’d be good to know exactly what is downsampled and to understand why 88.2/24 isn’t chosen. It’s all very well saying 44.1/16 is great but 88.2/24 must be better (I have the Billie Eilish CD and the 44.1/24 download and the download is far better than the 16 bit version).

I find it hard to believe any bit rate increase or oversampling would improve the sound of Billie Eilish. Ha ha.


Most, if not all, of the Japanese SHM-SACD’s that I have are single-layer…

Good point, but I have only one or two of those.

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I’d still like to hear about downsampling!

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Downsample is compromised compared with native DSD. When I had the DMP it downsample to 24 bit 88.2 when the handshake failed and it don’t sound nearly as good as when there is the handshake. You should try and get a matching DAC and take advantage of the DSD layer period. It is that much better.

When I have downsampled DSD using the Weiss Saracon program the PCM has very different sound depending on which dithering filter I used, TPDF or POWr or none. Does DMP use dither?

This is taken from page 10 of the PST Manual:

Users can select what comes out of this output when an SACD is played. The choices are: SACD (DSD), Stereo downsampled from the SACD layer (PCM), or Red Book audio (PCM).

Having said that it goes on to say:

The pure DSD output on an SACD disc’s master layer is available only through the I2S output. If that connection is not present, the PST will default to playing the SACD’s CD layer.

So there appears to be some downsampling option resulting in the ability to get PCM (as opposed to DSD).

It looks like the manual may be wrong - some clarification is therefore required from PSA (maybe the term should be downmixing of more than two channels?).

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They do appear to be contradictory at first. Unless the 1st quote deals with a SACD that is not a hybrid while the 2nd statement refers to a hybrid SACD.

Clarification/confirmation from PSA would be a good thing.

The paragraphs you quote are under the “I2S Sources” section of the PST manual, and would apply when you connect the PST I2S output to an I2S DAC input.

The manual also says:

Note that all of the PST’s outputs are active at all times. There is no need to select which output is operational. If desired, multiple outputs can be connected to multiple DACs.

So, if all outputs are active at all times and the laser is reading from the DSD layer there must be some downsampling to get data out of the coax and optical outputs (and I’d want the downsampling to be to 88.2/24 rather than the inferior 44.1/16).

[Update - if the manual explained all options within the Settings menu all would be clearer. For example, I’d like to see whether it offers the option to state what downsampling speed is wanted, e.g. choose between 88.2/24, 44.1/24 or 44.1/16]

[Update - does the PST have separate lasers for DSD and CD? - that would possibly explain why downsampling is thought to be unnecessary]

Just a nudge to keep this visible to PSA!!!

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Let me ask a different question. If I connect a Direcstream dac via I2S and play the DSD layer, what comes out of the coax connector?