Which transport with my Jay's Audio DAC?

The best I can tell about the NuPrime digital transport (CDT-8 PRO) and companion DAC (DAC-9) is that the CDT-8 PRO transport can be selected to up sample to higher sampling rates ONLY for the purpose of digital stream data transmission via a compatible digital cable to a downstream DAC (e.g., NuPrime DAC-9) capable of receiving and processing that data stream for a particular digital cable and input. That DAC processing can be done with the received input native digital signal rate from the transport, or with some up- or down-sampled digital signal rate once in the DAC.

That is--and despite what the NuPrime CDT-8 PRO manual and literature states--the NuPrime CDT-8 PRO does not up sample and then down sample to the target signal rate before sending out its digital data stream to the downstream DAC. My Theta DAC confirmed that only the CDT-8 PRO output streams clocked at 44.1kHz and 48kHz would lock on the Theta DAC input receiver.

And I am not convinced that one can strip jitter from a data stream simply by applying up sampling and down sampling tricks. As I said, the native output circuit jitter is quite high from the CDT-8 PRO. Maybe Steve Nugent can chime in on this point.

celander:
Here's what happens when one presses the the Nuprime CDT-8's OS button [the central one on the bottom row of the remote], and then dials up to the desired PCM OS rate, say, 48K x 2 = 96K [by pressing the right button on the bottom row]... the DACs I have used, the Jay's Audio and the Denafrips Pontus, detect that OS input [PCM 96K], while registering that rate in their displays [an LED display for the Jay's, a light for the Denafrips], and then convert that rate to an analogue signal, which they then send to the preamp.

That is what happens, mutatis mutandis, for the other PCM OS rates and the DSD OS rates available on both units.

So, with all due respect, I do not know know you mean when you say that "the NuPrime CDT-8 PRO does not up sample and then down sample to the target signal rate before sending out its digital data stream to the downstream DAC."

If your Theta DAC does not have OS-capability, then, OF COURSE, it [yourTheta DAC] "confirmed that only the CDT-8 PRO output streams clocked at 44.1kHz and 48kHz would lock on the Theta DAC input receiver." That is what a NOS DAC does. But that is not what the OS-capable Jay's Audio and Denafrips DACs do when fed an OS signal from the Nuprime CDT.

I have to wonder.... Do you have some brief to write against the Nuprime DAC? Otherwise, why are you denying the obvious: It does have the capacity to send OS signals to OS-capable DACs.

Finally, I stress a point I made earlier in response to itzhak1969: I have no firm commitment to the Nuprime transport; in fact, as an audioholic, I am positively looking for an excuse to upgrade to the Jay's Audio transport.... If upgrade it would indeed be, given its lack of OS-capability.

Of course, if one has already assumed that NOS all the way is superior to OS, then the choice between transports is settled. But no one so far has given me a definitive reason to think that that is the case.

OP: "Here’s what happens when one presses the the Nuprime CDT-8’s OS button [the central one on the bottom row of the remote], and then dials up to the desired PCM OS rate, say, 48K x 2 = 96K [by pressing the right button on the bottom row]... the DACs I have used, the Jay’s Audio and the Denafrips Pontus, detect that OS input [PCM 96K], while registering that rate in their displays [an LED display for the Jay’s, a light for the Denafrips],...[snip, snip]"

That is what I am saying here: "The best I can tell about the NuPrime digital transport (CDT-8 PRO) and companion DAC (DAC-9) is that the CDT-8 PRO transport can be selected to up sample to higher sampling rates ONLY for the purpose of digital stream data transmission via a compatible digital cable to a downstream DAC (e.g., NuPrime DAC-9) capable of receiving and processing that data stream for a particular digital cable and input. That DAC processing can be done with the received input native digital signal rate from the transport, or with some up- or down-sampled digital signal rate once in the DAC."
In short, I agree with you. So where is the disagreement? It’s not with me, so you need to elaborate your position if you disagree..

OP: "So, with all due respect, I do not know know you mean when you say that "the NuPrime CDT-8 PRO does not up sample and then down sample to the target signal rate before sending out its digital data stream to the downstream DAC."

I said the following: "That is--and despite what the NuPrime CDT-8 PRO manual and literature states--the NuPrime CDT-8 PRO does not up sample and then down sample to the target signal rate before sending out its digital data stream to the downstream DAC." It is not my language, but that of NuPrime. Your complaint is misdirected.

OP: "If your Theta DAC does not have OS-capability, then, OF COURSE, it [yourTheta DAC] "confirmed that only the CDT-8 PRO output streams clocked at 44.1kHz and 48kHz would lock on the Theta DAC input receiver." That is what a NOS DAC does. But that is not what the OS-capable Jay’s Audio and Denafrips DACs do when fed an OS signal from the Nuprime CDT."

My Theta DSPro basic IIIa is an 8x OS DAC. Is the CDT-8 PRO transport capable of up sampling a 44.1kHz signal to a 352.8kHz signal? Yes, but the CDT-8 PRO failed to deliver the signal to the Theta DAC. Why? Because the Theta DAC only accepts 44.1kHz or 48kHz INPUT data signals and only over-samples the digital data stream to 8x during digital processing once in the DAC. So you see, it depends upon how the DAC processes its digital signal after receipt, and OS means a lot of different things depending upon a given DAC. This may be more an issue about up-sampling digital data streams at an input receiver of a DAC vs. oversampling digital data once inside the DAC. Just saying..

OP: "I have to wonder.... Do you have some brief [sic] to write against the Nuprime DAC? Otherwise, why are you denying the obvious: It does have the capacity to send OS signals to OS-capable DACs."

I have no bias against or in favor of the DAC-9. I did not like the CDT-8 PRO transport, as it has high output jitter and did not improve the SQ of my audio system. I have no opinion about OS v. NOS transports DACs of any manufacture.

"The OS-capable DACs I am acquainted with and discussing here, the Jay’s Audio DAC and the Denafrips Pontus, will not perform an OS conversion of an incoming digital signal sent from a transport unless that transport sends an OS signal. It’s that simple"

You are really don’t understand what I am trying to explain you CD transport shouldn’t be OS this is the DAC duty so if you insist to do OS you should buy for example the Jay transport and since the Jay DAC is no OS find another good DAC with OS capability.
Everybody here trying to explain you that Jay combination of transport and DAC is very good option despite it doesn’t do OS and OS capability is not necessary improving the sound (and IMO it might degrade it ! ) and that the Nuprime is not a very good transport (its OS capability doesn’t make it good gear!) but your wrong assumption that OS is a must to achieve good sound making you not listen to what people trying to explain to you here so really there is no point to continue explain to you what you should do or not do.

OS process making improvements is a myth .it don’t. Only if a professional studio taking a low resolution recording and remaster the original recording in a complicated and expensive process this can be a real improvement OS if the studio stuff do it right.

There are some transports that upsample, here is CD transport that allows you to pick which sampling frequency you want it to stream (switch on the back), I think remembering a CAL or Arcam transport only, that did that too.

Choose which output sampling rate 44.1kHz / 88.2kHz / or 96kHz you want.

http://www.olasonic.us/nanocompo/nanocd1.html
3 sampling frequencies, 44.1/88.2/96kHz, can be selected to compare the sound difference

Cheers George