As a few of you know, I've been experimenting with s/pdif transfers from the 722 into the SEK'D Prodif+ sound card. I bought the 722 last Fall. I used a firewire cable from a local computer store for all of my transfers. Dale and I continually noticed that the 16 bit CDs seemed too dull compared to the master recording. Even taking the 24 bits into consideration, the CDs seemed to lack fidelity. Something did not seem right.
We set out on a quest to minimize the loss in fidelity that happens going from 24/96>16/44. It started with an experiment using Vibrapods under the laptop and 722. We use them under everything in our hi-fi systems. The difference was noticeable. Noticeable enough to make me delete the original and archived files of the Steve Kimock show I had just finished and start over. Dale came over and agreed after only a short amount of time spent listening.
Not long after, we picked up Atlas Cables for Eugene Hi-Fi. We stumbled onto a UHF review digital cable lengths, testing the theory that 1.5m s/pdif cables sound better than 1.0m s/pdif cables. Atlas' Opus All Cu 1.5m s/pdif wound up replacing their existing s/pdif cable in their reference system. It was around that time we started talking about trying the old-school, DAT style s/pdif transfer again. We ordered an Opus All Cu 1.5 meter cable for the project.
Later that Spring, we bought an FIM Energy Center for our reference hi-fi system. It's an a/c distribution outlet box. No filters, just top-knotch raw materials and a dedication to excellence. It's powered by a van den Hul Mainsstream Hybrid a/c cable that has passive filtering qualities to control noise in the a/c line. We use Quantum's QRT technology to control EMI/RF Intererence instead of dynamic-robbing series filters. This a/c maintenance package easily takes an audio or video system to the next level. It's profound effect on the hi-fi system left us no choice but to plug the computer and 722 into it when we started doing the real time spdif transfers.
We recorded six shows this past summer, doing real-time transfers on all of them.
edit for clarity: We waited until the end of summer before doing any direct comparisons. Our first impression [/b]
(before any direct comparisons) was that the s/pdif transfer was better. The 16 bit sources seemed to be comparing more favorably to the original 24 bit sources.
We chose this stretch of music for our first serious look at the two methods.The Source:
String Cheese Incident 8/5/2006 1st set
"MLT>New Pollution>MLT"
Neumann km 184s>van den Hul Orchid mic cables>Sound Devices 722 2nd row, dfc in the TS.
The Cuthbert Amphitheatre is an open air venue with a copper half-shell over the stage.
What We Heard:
The firewire transfer came up noticeably short on fidelity. It has a darker, less extended sound. The bass is less detailed. The overall sound is muddy. It lacks in dynamics as well. Myself and three other people have all easily agreed on which sounds better.
What We Saw:
I have not done any waveform analysis on the samples. I don't know how. Looking closely at the waveforms on my laptop's 1900 dpi widescreen, they look identical. I'm not sure what I was expecting to see, but I wasn't ready for that. I would appreciate it if someone would do the analysis to confirm this.
Please download the files and compare them if you are currently using firewire. I'm sure the technical conversation will flow.
Thanks for reading. Have a great weekend,
Chris
http://eugenehifi.com/Downloads/Transfer_Comparison.htm