Hey folks. Just a theoretical question… If I played an SACD in a PWT which was outputting via coax rather than I2S, does the PWT just play the disc in standard way rather than pull off the raw DSD data? Or does it just smoosh the DSD data to get it out via coax?
The PWT didn’t have the ability to read the DSD layer from an SACD. It would be reading the redbook layer. If I’m not mistaken, if you put a non-hybrid SACD in the PWT, it wouldn’t play at all.
Sorry I wrote the wrong transport name! So… same question for a DMP or PST?
Thanks.
No one has ever made that mistake, so make sure not to do it again… 
So the DMP would do this. It would read the DSD layer, convert it to PCM, and then output it via COAX. The PST is a little different. If you select it to read the DSD layer, it will only output the signal via I2S. No audio through COAX. To get SACD playback out of coax, you have to select it to play the redbook. Meaning it’s reading the redbook layer, not the DSD.
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If I understand you correctly then, the PST won’t play a non-hybrid SACD (one with no redbook layer) at all if the drive isn’t connected by i2s? Or am I misunderstanding?
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I’ve literally got a spreadsheet of PS Audio models … otherwise I start referring to PMT … PTSD … Paw Patrol … sheesh
That’s how I took it … without I2S you’ve got a CD player not an SACD player
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CD Transport! Although with the benefits of the galvanic isolation, digital lens, etc.
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@Craig_Burgess You’re right. That’s my understanding as well. It makes sense but would still be cool if it could convert the signal to PCM.
@hiace_drifter I still crack up when people call in asking about our “DreamWave DAC.” Happens at least once a month and makes me laugh every time.
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The confusion created by that whole alphabet soup is exacerbated by the fact that, at least so far, the initials “PST” don’t automatically create a link like DMP and PWT and SGCD do. 
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I have added PST as a linked word which, when clicked on, brings you to its product page.
Thank you for mentioning the lack of a link. 
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IIRC, when reading reviews, I got the impression that you can read the DSD layer and using the Coax output get a downsampled output better than 44.1/16, i.e. you can get 88.2/24 (or maybe 96/24). I’ve just looked at the PST manual but this doesn’t go into details of what can be selected via sub menus so I don’t know whether I’m imagining that you can get better than redbook datarate via coax.
You can only get the DSD layer of a SACD from I2S. You can only play the CD layer or a CD thru the Coax and other outputs. I tried. But from Coax you can get DOP 64 from the USB input playing files.
This is on page 10 of the DMP manual:
When selected, the stereo SACD layer will output stereo DSD to an authorized PS Audio I2S connected DAC, or a downsampled PCM version at 88.2kHz/24 bit to a non-PS Audio DAC.
This is on page 9 of the DMP manual:
In non-PS Audio connected DACs, choosing an SACD stereo or multi-channel layer will provide a downsampled PCM version at DMP’s outputs. This downsampled PCM version, output at 88.2kHz/24 bit, is generally superior to the RedBook CD layer.
So, is it the case that with a PST this DMP 88.2/24 downsampled PCM output from the DSD layer is no longer possible?.
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With the PST, the DSD layer will output native to a non PS Audio DAC thru it’s I2S output as many including myself have done it with the Holo May DAC as well as other I2S DAC’s.
Unfortunately that’s no use to me. My crossover doesn’t have an i2S input (I guess there’d be a protocol converter that I could use).
Hopefully someone from PSA will explain why they don’t output 88.2/24 via coax.
Simply put, the PST doesn’t do any down sampling like the DMP used to. If you want to listen to native DSD, you need to have a DAC that supports I2S. I think standard Redbook sounds so good with the PST, I don’t care that it doesn’t do 88.2/24 downsampled for SACDs. That was never applicable for me.
Thanks James for that clarification. Because the manual says that all outputs are active at all times and because it also says that it can play a downsampled version of the SACD layer that the sample rate that’s converted to would be 88.2/24. Oh well.
Do all SACDs have a redbook layer?
No. Only those labelled as “Hybrid” have dual layers: one SACD and the other Red Book CD.
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