Is USB overrated as decent digital source?

Mikechai - No. 1 is the most costly, but well worth it, particularly the Superclock4.

BTW - I demonstrated my new I2S reclocker, the Pace Car at THE Show two weeks ago in Las Vegas. It's amazing how much of a difference it makes when the jitter is so low to be inaudible. Most audiophiles have no idea how much jitter they are listening to and how audible it is until its gone. This is the real flaw in real-time CD playback IMO.

Steve N.

There is a very nice professional product from TCelectronics, named Konnekt 24D (or 8D with less connection and DSP). It is a professional A/D, D/A converter mainly for musicians with Firewire connection.

They developed their own software driver for Mac and Windows, they have their own clock regeneration and jitter filtering and it can be used as a Firewire - SPDIF converter as well. This is how I am using it with a Macbook and an Altmann Attraction DAC (with all the clocking and jitter scrambling options). It sounds wonderful, with better dynamics, timing and transparency than any USB - to SPDIF converter I tried. The Altmann Attraction DAC / Konnekt 24D / Macbook is an extremely musical and emotional combination, I changed an Accuphase DP-100/DC-101 system to this one, and never looked back. Since I am using this system I almost doubled the number of my CDs, and I had more than 1000 earlier.

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...