Users of the AES/EBU input and cables

[Pim]

Interesting to read that no-one here seems to know that the RCA connector itself isn't 75 Ohm at all. There's a bit written about it on the Blue Jeans cable web site (sorry, due to the slow internet here at work I can't open it to copy a link) From what I remember reading the RCA connector has the wrong inside and outside diameters to make it true 75 Ohm. They sell a Canare connector that's built to be as close to 75 Ohm but not right there. So the real question here should be; What impedance is an RCA connection?

This brings me to the Crystal Cable. It's definitely NOT a 75 Ohm cable looking at the size of it so without hearing it i would say it sells on the 'enormous change in the sound it makes' when all it really does is loose ones and zeros because of the impedance mismatch on both sides of the cable. And maybe that's why some on this forum have had better results with 'true 75 Ohm' cable (or near enough)

That's why I posted:

"Wish Devialet had installed BNC connectors for this link."

Interesting that you can tell how the Crystal Cable performs just by looking at.

I can't. But what I can see is a cable constructed so thin it cannot possibly be 75 Ohm unless they used some very special dielectric insulator (around the inner core). The impedance is directly related to the size and material of the inner core.

I've done a few years in antenna and satellite installation and that gives you a bit of insight into all this. I don't claim to be an expert but a few things are clear; Digital satellite signal goes into the Giga Hertz and runs without any problem or interference through a $1.50/m solid core quad cable over 30m or more. Attenuation isn't an issue, nor is interference from outside. That same cable does an equally good job at transferring analog tv signal which is in the Mega Hertz. I don't know at what frequency digital audio runs but I guess it's somewhere in between.(700Mb on a disc, running for an hour. Not sure how to do the maths but near enough) I just can't see how something as complicated as a digital video signal can be transferred through ordinary coax without any issues but when it is an audio signal suddenly we need hyper expensive super duper cable. I guess if you were trying to sell a very expensive video cable and show your customer the 'difference' in your shop and they can't see any they will tell you your full of it. It's because with hearing it is harder to tell that 'difference' (move your head an inch of two and the sound is different so is it you or is it the cable) that people fall for expensive cables.

Devialet has shown the world that you don't have to spend mega bucks to get a great sounding amp. Surely there is a minute possibility that you can get equally great sound with a well constructed coax cable that doesn't cost a fortune?

Nearly forgot. I agree; BNC would have been great!