DAC connection preferred?

OK, DAC fans; Do you have a preference for connecting your DAC to a CD Player or transport-- coaxial, optical, RCA, or other? If so, why the preference?
It depends upon how the I/O is implemented. What works best for one combo might not be best in a different setup.
My DAC connection Preferred is PS Audio DAC BRIDGE II with a cross over Cat 6 cable from my Mac Mini. The Bridge changes everything better and is a must have component going forward for me.
This is strictly my opinion, but I have owned many, many DACs and transports and servers.

In Order:

1. AES/EBU (if available)
2. Coax with BNC connection
3. Coax with RCA
4. ATT Glass Fiber
5. Toslink

(The above list is using a proper cable with the proper terminations and impedances).

I have never owned any gear that had Firewire or the I2S interface or any other proprietary connections. Those are "supposed" to be better.
I agree with Onhwy61 - for instance...

I bought a Bifrost DAC with the USB port to stream from my iMac.

In order to mitigate the obvious USB related issues, I tried a couple of USB cables and settled on a double cable that is joined at the DAC
- one cable was for power the other for signal

Even though this worked extremely well, I then decided to try a v-link192 USB-SPDIF converter connected to the DAC via an RCA SPDIF

It was quite clear the USB interface on the Bifrost was inferior to the USB interface on V-link192.

However, the SPDIF input on the DAC appeared to be as capable as the SPDIF output on the V-link192.

The resolution improved dramatically.

My guess is the USB "interface" selected for the Bifrost had more to do with its very sffordable price point

So, I am assuming that between two connected components, similar cost saving measures that may have been applied during their manufacture, may result in similar inconsistent results between their individual digital inputs.

Basically - its a craps-shoot - simply because, the actual circuitry within a components digital interface may offer a different level of performance compared to the component it connects to.

Quite often, the actual "Interface Specification" only identifies a minimum level of performance in order to work.

I'm still using the virtually defunct firewire via Metric Halo. I'm not sure how much 'better' it is than anything else, because the cables, OS, hardware, software, etc., all makes a difference anyway.

If my DAC came with an optional SD card reader maybe I could hear what it actually sounded like without the extra pathways and processes. Perhaps Invicta is onto something there.

With my Wadia separates which had all connections, I found ATT Glass Fiber the best, used with indexing gel on both ends.

Cheers George