How can I tell if I need a better clock for my DAC?


I was interested in the responses to a related post by leemaze this week, saying that a Synchro Mesh was a good way to improve a DAC with subpar jitter.  I have a Cambridge CXU, with an inboard DAC; how could I determine how much jitter it has? 
cheeg
Proper spdif connection between transport and dac should be made using 75ohm bnc.
rca is not true 75ohm and this can also introduce jitter.

George - You are dead right.  Just buying a 75 ohm cable with BNC's does not guarantee that the BNC connectors are 75 ohms either, particularly from Marketertek.  I have 75 ohms cables with 50 ohm BNC on the ends from Marketertek.

Also, BNC to RCA adapters should be 75 ohms as well.

Here are some cable jitter measurements, including some from Markertek:

http://www.audiocircle.com/index.php?topic=154425.0

Steve N.

Empirical Audio

I suspect a lot of new dacs sound better than your Cambridge but it doesn't have to do with just jitter.
Thanks for the additional references on dacs -- that's a good start!  As for the quoted comment, @headphonedreams may be right about that, but it leads to a more basic question.  By my standards, the Cambridge is a fairly expensive (and well-reviewed) unit, but the sound it gives to a Redbook CD doesn't compete with that of my more modest phono (Technics SL-D2 with a Nagoka MP-110).  Can I expect to get comparable sound quality with a CD player and DAC, without spending well over $1000, or is this the unavoidable result of the 44/16 format?


The difference with BNC and RCA is BNC connectors are specifically designed to terminate to a particular coax cable and make a clean impedance transition.  This is why there are hundreds of types of 50 and 75 ohm BNC connectors.

Steve N.

Empirical Audio

By my standards, the Cambridge is a fairly expensive (and well-reviewed) unit, but the sound it gives to a Redbook CD doesn’t compete with that of my more modest phono (Technics SL-D2 with a Nagoka MP-110). Can I expect to get comparable sound quality with a CD player and DAC, without spending well over $1000, or is this the unavoidable result of the 44/16 format?

A confirmed analog guy, I have learned, but only within the past year, that Redbook CD can be as good (if not exactly the same) as a very good vinyl set-up. With more consistency as well as the usual digital advantages, digital has come a long, long way.

I also learned a long time ago that "well reviewed" in the audio press means practically nothing. Better to spend some time and energy on the forums. This one and head-fi and computer audiophile, for ex.

I did 2 things that brought my CD listening to a higher level than I ever thought possible. One cost a bit of money; one cost me nothing.

First I sourced a high performing DAC* directly from China. Not very expensive from my point of view, but still just a bit more than you may want to spend. But I think one can do well for less. Second, rather than use a CDP, I ripped all of my CDs to a portable hard disk which I had hanging around and played them through my (also hanging around) laptop directly into the DAC (easiest if the DAC has a USB input). Sound is better than using my Oppo to play disks through the new DAC.  Also, using JRIver I can control my digital listening entirely from my phone.

*And yes it has a femtoclock, in fact three of them.