[DACLadder]

RG402 works well for short 50 ohm cables. I bought from this Ebay vendor as I could buy in 2 inch increments for a custom install. They work well but have cheap connectors and may not be durable for years. But are fine if you plug them in and leave alone.
https://www.ebay.com/itm/BNC-male-p...-/172379907208?_trksid=p2349624.m46890.l49286

The Huber+Suhner cable from AfterDark is RG402. May be better built wire but the specs are similar to other RG402 cable stock. Hope AfterDark uses better BNC connectors. RG402 wire will handle voltages up to 1.9KV so there is no fear a 10M clock burning it out.
https://ecatalog.hubersuhner.com/media/documents/datasheet/en/pdf/84003502

 

[FredA]

RG402 works well for short 50 ohm cables. I bought from this Ebay vendor as I could buy in 2 inch increments for a custom install. They work well but have cheap connectors and may not be durable for years. But work fine if you plug them in and leave alone.
https://www.ebay.com/itm/BNC-male-p...-/172379907208?_trksid=p2349624.m46890.l49286

The Huber+Suhner cable from AfterDark is RG402. May be better built wire but the specs are similar to other RG402 cable stock. Hope AfterDark uses better BNC connectors. RG402 wire will handle voltages up to 1.9KV so there is no fear a 10M clock burning it out.
https://ecatalog.hubersuhner.com/media/documents/datasheet/en/pdf/84003502

Good point about the max voltage. I must have misread spec sheets, so thanks for rectifying, it is not a concern whatsoever. The Afterdark indeed uses better connectors. They are bigger and tighter.

 

[sajunky]

US dealership for Audio GD?​

https://headphone.guru/audio-gd-now-exclusively-at-underwood-hifi/
https://www.underwoodhifi.com/products/audio-gd

 

[DACLadder]

I hope the US seller is a solid resource for parts, service, and upgrades.

 

[XavierP56]

I have 3 RCA cables with GND+Shield on one side only. (Audio-GD cable, sommercable Epilogue, DIY sommercable based on Aqua Mikro 25)
For the 3 cables, the best combinaison is GND+Shield on SOURCE side (so on R-7HE21 side). There is bass, sound is fluid and airy. Perfect !
Theory would say otherwise : GND+Shield should be on Preamp side. In such case, I think something is missing : No vibrance in the highs.

Any thoughts ?
Thanks !

 

[FredA]

Heads up, the r7 mii is finally offered! This is a great news!

http://www.audio-gd.com/R2R/R7MK2/R7_MK2EN.htm

 

[sajunky]

I have 3 RCA cables with GND+Shield on one side only. (Audio-GD cable, sommercable Epilogue, DIY sommercable based on Aqua Mikro 25)
For the 3 cables, the best combinaison is GND+Shield on SOURCE side (so on R-7HE21 side). There is bass, sound is fluid and airy. Perfect !
Theory would say otherwise : GND+Shield should be on Preamp side. In such case, I think something is missing : No vibrance in the highs.

Any thoughts ?
Thanks !

Well, it is prefered, but not always a case. Regenerative power supply beast has its own rules.

What kind type of a cable do you use? Not a make, as I wouldn't be able to get any clue. From my experience grounding shield on one side is beneficial only in cases when ground wire and a live wire form a twisted pair. A reason is explained below.

You can also terminate shield in such way:
- ground + shield on one side
- ground & shield joined by a resistor 100k Ohms with 1nF styroflex capacitor in parallel on the other side.

It is what I would suggest to do. It can save lot of money on expensive cables.

How it works? It leaves ground loop open for DC, but terminate shield for high frequencies. It should fix a problem that shield acts as an antenna on the open side spreading EMI. Twisted pair is less sensitive to a common mode interference, so it is helping in many cases, but EMI presence is evident in your case. So either terminate on both sides or use a trick as above.

 

[XavierP56]

Thanks.
If you look at Sommercable site, you can see detailed specs for Aqua-Mikro25 (2 conductor, probably twisted with 2 shields) and Epilogue which has 4 pairs but I don't have much details.

All I can say : With those 2 sommercable and Audio-GD cable I have great results when shield + gnd is on R-7HE21 side

Why do you say I have an evident EMI issue ? What can I do ?

 

[XavierP56]

R-7HE21 vs R-7HEMk2
R-721 vs R-7Mk2
Similar price, similar performance.
This is very confusing offering IMHO.

 

[sajunky]

If you look at Sommercable site, you can see detailed specs for Aqua-Mikro25 (2 conductor, probably twisted with 2 shields) and Epilogue which has 4 pairs but I don't have much details.

All I can say : With those 2 sommercable and Audio-GD cable I have great results when shield + gnd is on R-7HE21 side

On short distances you can use twisted pair taken from Cat5 UTP infrastructure type ethernet cable (not a patch cable), no shield. The best performance in many cases, trust me.

 

[sajunky]

R-7HE21 vs R-7HEMk2
R-721 vs R-7Mk2
Similar price, similar performance.
This is very confusing offering IMHO.

Yes when using USB connection. It should be better on the I2S connection when no external clock is used. Bigger difference in SQ when I2S source is poor quality.

 

[XavierP56]

Ethernet cable, Excellent idea, will try it . How do you wire them ?

I would say
Left:
2 pairs : Hot point
2 pairs: Cold point

Right:
2 Pairs: Hot point
2 Pairs: Cold point

So a single Ethernet Cat 5e can transport both L & R channels ?
What do you do with the shield ? Connect both sides to the cold point or leave it disconnected ?

Thanks.

 

[sajunky]

Not. I take two pieces of a quality solid core Cat5 cable with a good internal isolation like PTFE or at least polyolefin, strip it from the PVC jacket, take one pair, discard the rest, then do the same with the other piece, using the same pair (I mean colour the same). Now I have two lenghts of twisted pair of the same colour for left and right channel. Copper is an audiophile quality and insulation too. The next step is to add a new jacket and solder plugs, that's all. Or extract a tube from the foamed or airspaced polyethylene satelite cable. It ads a distance between a pair of wires and the outer jacket. A more airspace between twisted pair and a jacket, less losses on a dielectric. In most cases there is no need for a shield.

EDIT: I noticed, it is my post #1000.

Ethernet cable, Excellent idea, will try it . How do you wire them ?

I would say
Left:
2 pairs : Hot point
2 pairs: Cold point

Right:
2 Pairs: Hot point
2 Pairs: Cold point

So a single Ethernet Cat 5e can transport both L & R channels ?
What do you do with the shield ? Connect both sides to the cold point or leave it disconnected ?

Thanks.

 

[XavierP56]

Ok thanks ! I will try that ! Using one piece like I suggested for 2 channels is a bad idea ?

 

[sajunky]

Ok thanks ! I will try that ! Using one piece like I suggested for 2 channels is a bad idea ?

Different colour pairs have different twist rate in order to limit crosstalk. For digital transmission it works, but you don't want to introduce phase errors, do you?