Newbie question: how does i2s compare to a dac with a clock feeding the transport (or other processor) in terms of jitter? I've been toying with the idea of putting a behringer deq, which has a clock input, after my squeezebox, and in front of a lavry blue or other dac with a clock output. I'm not totally married to the squeezebox, so a solution requiring a computer instead isn't out of the question for me.
I'm not totally innumerate, but certainly have a _lot_ to learn about this stuff. There's a lot of reading for me to do before I have any real clue, so please excuse me if this seems like a stupid question.
The jitter with my I2S converters is extremely low and it provides ALL of the clocks needed by the DAC chip. Word-clocks (like the Behrenger needs) on the other hand only supply the low-frequency clock. Most good DAC chips are actually clocked on the bit clock, not the word clock, so a word clock like that used in the Behringer will not be very effective IMO. Besides, the Lavry would have to have a word clock output to go to the Behringer in order to be effective, and I would bet that it needs a bit clock, not a word clock to get low jitter.
The Lavry also reclocks the data with their special clock technology which is technically good, however my customers have reported that even the Lavry sounds better when it is driven by my Off-Ramp Turbo 2 with S/PDIF output. This indicates to me that the Lavry clock technology does not completely eliminate the effects of jitter on the input. It is evidently not as good as the theory would predict.
I recommend that you do not put too many "band-aids" in the digital path. Try to keep it simple and low jitter with the clocks, and use technology from one source. It is not good to mix-and-match when it comes to digital signalling. The interfaces do not work that well together. There are a lot of issues, such as slew-rate, voltage levels, termination and compatibility involved, and even sometimes timing considerations.
If you like the SB, then I would recommend that I mod it to add Superclock4 and put an I2S output interface on it. Then drive a Benchmark DAC-1 with I2S input interface. This will produce superior sound to anything you can buy. Short of doing this, modding the SB to improve the clock, power supply and S/PDIF output to drive the Lavry with a low-jitter signal would be my next-best choice.
If you want something wireless that is already available and will outperform your SB, then you should consider my Off-Ramp Wi-Fi with S/PDIF output or if you are willing to change DAC's, the superb Off-Ramp Wi-Fi with I2S output. These both use iTunes.
Steve N.
