Alright, I went to the friendly Hifi shop rather close to home last week to buy a new amplifier and speakers. The sales person tried to convince me that I needed a high-end CD player as well, because connecting just the digital output of my Bluray player would not sound reasonable. He quoted "jitter" as the reason, but his explanation sounded way less than convincing.
Soooo... this is what I found out so far:
- The SP/DIF interface between the Bluray and the amplifier runs a fairly standard block protocol which transmits data in large blocks. Data transmission is protected by checksums - so either the bits arrive correctly from the CD, or they do not arrive at all. So from all I can see, the DAC will see exactly the same bit stream from a 50 pounds Bluray player, as from a 5000 pounds CD player.
- The data is transmitted in blocks, and the interface can run at multiple speeds - 44.1 and 48kHz as the most common frequencies. Because of the block protocol, the data is not arriving in a constant stream, but in chunks. Hence, the DAC needs to have a buffer. It also needs to generate a clock signal to get this data converted into voltage at the right speed (unless someone really wants to derive a signal with a completely different frequency from the bus clock - which sounds like a fairly outlandish idea).
So - can anybody explain where this jitter is supposed to come from?
Thanks a lot!
Soooo... this is what I found out so far:
- The SP/DIF interface between the Bluray and the amplifier runs a fairly standard block protocol which transmits data in large blocks. Data transmission is protected by checksums - so either the bits arrive correctly from the CD, or they do not arrive at all. So from all I can see, the DAC will see exactly the same bit stream from a 50 pounds Bluray player, as from a 5000 pounds CD player.
- The data is transmitted in blocks, and the interface can run at multiple speeds - 44.1 and 48kHz as the most common frequencies. Because of the block protocol, the data is not arriving in a constant stream, but in chunks. Hence, the DAC needs to have a buffer. It also needs to generate a clock signal to get this data converted into voltage at the right speed (unless someone really wants to derive a signal with a completely different frequency from the bus clock - which sounds like a fairly outlandish idea).
So - can anybody explain where this jitter is supposed to come from?
Thanks a lot!