Is a good transport a good transport they all sound the same; it's the DAC and amps that make the sound what it is? Like can I improve my CD sound by replacing my Cambridge CxC transport?
I'm not familiar with your Cambridge, but all parts and components quality effect the final outcome from my experience. The best transport I've had is my current one.
Transports do make a difference and in my experience a significant one. In the price class that your Cambridge lives it is a well respected piece, much as my Audiolab is. I think it would take a significant investment to improve on what you have.
Transports can make an enormous difference. The CXC is very good for the price, I felt that it was a huge step up from using a high end blu ray player as one. Every one I’ve ever heard sounds different, but you need to make a pretty big step up for something to be objectively “better” with these things.
Is there a buffer in the stream? Does the transport feed a buffer and the DAC request delivery? Or is it fed to a buffer in the DAC and then clocked? Either way your transport would not be the weak link. Regardless yours is well regarded. And CA build great stuff and has been in the digital sector a long time.
I am virtually 100% physical media. My LPs are older than my CDs, but I do have CDs going back to when they were first produced in the early 80s. I just traded in my old Onkyo CD player for a Denafrips Aries II DAC and the Denafrips Avatar Transport. Had the DAC first and used it with the Onkyo but had a feeling it could go further. WOW. Huge change in presence and detail of the sound. I had an instinct to grab a classical CD first as a test - Shostakovitch's 5th symphony. I had this disc for years and felt like I was hearing it for the first time. So yeah, transport matters.
There has to be a buffer in the transport to do CIRC decoding of the data on the disc, then another buffer to create the SPDIF serial data stream. The DAC must have a buffer to de-multiplex the left and right audio channels and do serial to parallel data conversion.