Long digital interconnect: is it a problem?

Posted by: Massimo Bertola on 21 May 2011

I've deleted my previous post because it was not clear.

The question: I want to connect my DVD player with a digital coaxial cable to my Supernait's digital input. Is it a problem if the cable is quasi 8 mt long?

I know that I can't feed my SN with DD or DTS signal, I plan to downmix it to PCM stereo (if it can be then fed through the digital output).

Thanks,

Massimo
Posted on: 21 May 2011 by Gale 401

Massimo,

You should be OK with that length of cable.

I have run longer with no problems.

G.

Posted on: 21 May 2011 by tonym
As Gale's posted, that'll be fine. I use a 15m co-ax. and same length optical with no problems.
Posted on: 21 May 2011 by Massimo Bertola

Ok, thanks.

Have a nice Sunday,

M.

Posted on: 22 May 2011 by Simon-in-Suffolk
Hi, If the cable is correctly designed and has a 75 ohm characteristic impedance, and your source and destination are also well designed with 75 ohm characteristic impedance,( naim should be fine) then the length won't matter. Try and keep away from RCA type connectors unless they have been specially modified.

However regular RCA has an impedance around 25~35 ohms. Impedance mismatches cause reflections, and then 'differences' may be heard with different cable lengths.

Posted on: 22 May 2011 by GreenAlex
I am using a really, really cheap (9&euro 15m long coax cable from my computer to my AV2 for party purposes with no problems at all.

Same cannot be said for optical (toslink) cables. 5m are usually ok. 10m are usually ok,but occasional dropouts. Add a connector to extend say a 5m and a 10m and i get dropouts.
Posted on: 27 May 2011 by Massimo Bertola

Hi,

I've just done an 8 mt long coaxial interconnect with satellite cable, 75ohm, double screen and able to manage gigabytes of signals, according to the dealer: €1,20 per meter, plus 2 decent RCA (I don't even know how to solder BNCs, and both my DVD player and my SuperNait have RCAs) plugs: €5.

Well, an Oppo DV980H into a SuperNait('s Dac) makes rather decent music!

Thanks & cheers.

M.

Posted on: 28 May 2011 by tonym

Yep, that's the best way to do it Max. Works as good as any expensive cabling I've heard so far.

Posted on: 29 May 2011 by Simon-in-Suffolk
Hi regular 75 ohm coax cable will be fine ( appropriate standard cable RG 6/u RG 6/uq and RG 7 - the q version has greater shielding)  however best to use BNC not RCA, as RCA.has completely the wrong char. Impedance and will cause reflections which might cause strange errors or increased jitter in the line (reflections smoothing the waveform and affecting clock recovery)
Simon
Posted on: 19 June 2011 by tonym
Originally Posted by Simon-in-Suffolk:

       

         class="quotedText">
        Hi regular 75 ohm coax cable will be fine ( appropriate standard cable RG 6/u RG 6/uq and RG 7 - the q version has greater shielding)  however best to use BNC not RCA, as RCA.has completely the wrong char. Impedance and will cause reflections which might cause strange errors or increased jitter in the line (reflections smoothing the waveform and affecting clock recovery)
Simon



Sorry, incorrect. There are a number of 75 ohm RCA plugs and sockets available; I use Canare versions on my DAC and then BNC into my Teralink USB/SPDIF convertor.
Posted on: 13 July 2011 by Laurie Saunders

Hi

 

I am interested in RCA plugs & sockets that have a 75 Ohm characteristic impedance

 

Does anyone know if WBT Nextgen are 75 Ohm ?

 

laurie

Posted on: 19 July 2011 by Massimo Bertola

I've been away from this thread and didn't know it had gone further. The developments interest me, too.

I too have used RCA connectors, because both my DVD player and the Supernait have RCA s/pdif sockets. Therefore, I am interested in knowing what real 75 ohm RCA connectors are available.

Max

Posted on: 19 July 2011 by tonym

have a look for Canare 75 ohm RCAs. Here's one  -http://www.canare.com/ProductItemDisplay.aspx?productItemID=40

Posted on: 19 July 2011 by Massimo Bertola

Hi,

thanks.

M.

Posted on: 20 July 2011 by tonym

Sorry Max, forgot to add, you need the 75 ohm sockets as well.

Posted on: 20 July 2011 by Mike-B

Search Mark Grant for Canare stuff

He makes excellent cables, made to measure & Canare