Is USB overrated as decent digital source?

I'll check out the TCelectronics.

What are the USB to SPDIF converter that you have tried?

The Konnekt24D is powered from the firewire cable, which is the computers power. Have you changed this to battery or external power?

I have no experience with firewire converters, but the others in this industry say that the firewire chips are very jittery compared to the USB chips. Have you opened it up to see what firewire chip they are using?

Audioengr, the Konnekt can be firewire bus powered or externally powered by 12V DC.

I have read the brochure and the features. It has anti-jitter technology called DICE II and the JET™ technology.

Clock and Jitter
Internal/External Sample Rates

44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz and 192 kHz / 43 to 193 kHz, jitter rejection at all rates
Jitter Rejection Engine
- JET™ technology in TC DICE II

Jitter Rejection Filter
<-3 dB @ 10 Hz, < -100 dB @ 600 Hz

DIO Interface Jitter
< 1 ns peak, BW: 700 Hz to 100 kHz

AD/DA Conversion Jitter
< 42 ps RMS, BW: 100 Hz to 40 kHz

Digital Output Phase
(stand alone and across network)
< 0.5 % of sample period

Digital IO interface jitter of < 1ns? That's very low...

I am using a JVC 5.1 receiver model rx-9010vbk. This particular receiver is equipped with a mini-USB port on the front panel. This port connects to the USB port on the computer, allowing to use the computer as the playback source. I have a G-4 Mac and use I-tune's exclusively to play my 19000 mpg's through my stereo system. This is done with the JVC receiver via usb port to usb port on computer. The receiver has Burr-Brown PCM 2702 DAC and my computer automatically recognizes it. I use to connect my receiver to computer with rca inputs, but USB is much,much better since the sound quality and fidelity is noticeably better since I am bypassing the internal sound from the computer by going usb direct from the receiver. I have done some research and have found there very few is any current model receivers that have usb port for connecting computer for mgp playback.

FYI, the soon-to-be-shipping Musical Fidelity
"X-DACv8 Tubed Digital-to-Analogue Converter"
has USB connectivity ...

http://www.musicalfidelity.com/products/xseries/xdacv8.html