[Chopin75]

Once should use small gauge wires to avoid skin effect. Ideally air or teflon as dielectric, and use a geometry that minimize vibrations, inductance and capacitance. Use multiple wires to minimize resistance. And pure occ if possible. That is pretty much all there is to it IMO and wire that do all this will sound better than good. Silver will produce better treble but can sound bright if not properly implemented.

I didn't know you can leave the ground pin empty as I was told to use a wire for that too and yes shielding can be used for the ground pin, I was told.

 

[DACLadder]

@FredA, @Chopin75 The M3's analog XLR inputs are rather high impedance - 98K ohms. So more likely to pick up noise but again use a balanced wire pair and common mode rejection. ACSS impedance is <10 ohms.

Single ended is a different story all together. The shield is not only ground potential but generally the signal return as well. And I have seen unshielded single ended cables offered for sale. This would never fly in the 2-prong AC days.

If I was building a cable I would connect the shield if available.

 

[FredA]

Yes, just leave pin 1 empty if no ground or "drain" wire - especially with short cables and modern 3-prong grounded AC systems. ACSS is such low input impedance that I doubt much if any noise coupling would happen with short cables. Plus common mode rejection with balanced, twisted pair of wires. But in certain cases adding a ground wire and even shielding may provide quieter performance in noisy environments. Or just connecting cable ground only on one side of the cable to minimize a ground loop (AC hum).

Not sure about the ground left unplugged. I have an audio-gd one and a double helix as well, both are shielded and pin-1 is connected on both side. In any case, I aways connected it on both sides on all my 3-wire braid cables. There are different opinions on this matter if you search the internet. Whatever sounds best really...

 

[FredA]

@FredA, @Chopin75 The M3's analog XLR inputs are rather high impedance - 98K ohms. So more likely to pick up noise but again use a balanced wire pair and common mode rejection. ACSS impedance is <10 ohms.

Single ended is a different story all together. The shield is not only ground potential but generally the signal return as well. And I have seen unshielded single ended cables offered for sale. This would never fly in the 2-prong AC days.

If I was building a cable I would connect the shield if available.

Since both phases on a balanced connection are not carrying the exact same current, the ground pin will act a bit like a return as well if connected. Otherwise things will have to get even in another manner so that you don't get a deficit of electrons on the source side.

 

[Chopin75]

Since both phases on a balanced connection are not carrying the exact same current, the ground pin will act a bit like a return as well if connected. Otherwise things will have to get even in another manner so that you don't get a deficit of electrons on the source side.

Is it not that the negative is the ground pin an the other 2 are traveling same direction (but with one polarity is reversed) for balanced? Or maybe I misunderstood ? IN any case, I thought the ground pin should be needed to work properly or it won't work ?

This kind of explains it:

http://www.aviom.com/blog/balanced-vs-unbalanced/

 

[FredA]

Is it not that the negative is the ground pin an the other 2 are traveling same direction (but with one polarity is reversed) for balanced? Or maybe I misunderstood ? IN any case, I thought the ground pin should be needed to work properly or it won't work ?

This kind of explains it:

http://www.aviom.com/blog/balanced-vs-unbalanced/

The two phases carry opposite voltage and thus current.

 

[DACLadder]

@FredA Then the line is no longer balanced in your example (leakage). A good example of a balanced, twisted pair are analog telephone lines which are generally not shielded and run in 25-pair bundles for long distances. In audio equipment these days the AC ground connections take care of equalizing electrons between chassis.

@Chopin75 The grounds in your link examples could be the 3-prong AC ground. Cable grounds are just tied to chassis ground as is the power plug ground. I would hope my precision audio signals did not run down the cable shield and through chassis ground to make the return path.

Grounding can be voodoo science especially with 2-prong AC connections. Go will what sounds best and trust your ears.

 

[DACLadder]

Audio GD is now offering linear power supply modules for DYI projects. DC regulator, two separate outputs, discreet parts, and no negative feedback. 200mA max current but higher is available upon request. I suspect similar circuits are used inside the AGD DACs and other products. $30US ea.

http://www.audio-gd.com/Pro/diy/PSU2019/PSU2019EN.htm .

 

[Chopin75]

Has anyone had any recordings that give a slight distorted buzz/split sound esp at the bass ? I have experienced such lately after I switched to XLR output on the R2R7. I thought it may be related to XLR but it also happens on the RCA output. I thought maybe from lose connections or tube issue etc but i still happened after I took most of my chain except a headphone pre-amp + headphone. Much more obvious with speakers but it can still be heard on headphones. Sounds a bit like the distorted sound from an unclean or defective Vinyl or with blunt needle on the vinyl.
I eventually just used my labtop and headphone (without the R2R7) but still can hear it if not as obvious.

The also happens on a CD from CDplayer to R2R7, and just mainly on the bass (cello playing deep sound) though with headphones the higher tones (flute/recorder) one can hear some dirty sound if not true distortion. They are newer original digital recordings, not transfer from old analogue vinyl/tapes

 

[Tango Sierra]

Is there a reason I can't get to the Audio-gd website when I'm running behind a VPN service?

 

[JaMo]

Hi,

Kingwa did it again! http://www.audio-gd.com/R2R/R27/R27EN.htm

 

[FredA]

Hi,

Kingwa did it again! http://www.audio-gd.com/R2R/R27/R27EN.htm

Just can't believe it, Jan! Where are the attenuators?

 

[FredA]

Has anyone had any recordings that give a slight distorted buzz/split sound esp at the bass ? I have experienced such lately after I switched to XLR output on the R2R7. I thought it may be related to XLR but it also happens on the RCA output. I thought maybe from lose connections or tube issue etc but i still happened after I took most of my chain except a headphone pre-amp + headphone. Much more obvious with speakers but it can still be heard on headphones. Sounds a bit like the distorted sound from an unclean or defective Vinyl or with blunt needle on the vinyl.
I eventually just used my labtop and headphone (without the R2R7) but still can hear it if not as obvious.

The also happens on a CD from CDplayer to R2R7, and just mainly on the bass (cello playing deep sound) though with headphones the higher tones (flute/recorder) one can hear some dirty sound if not true distortion. They are newer original digital recordings, not transfer from old analogue vinyl/tapes

Recording defects exist. Try another dac and see if it happens. Could be errors in your file as well. For instance, a scratched cd can produce errors on a file when ripped.

 

[DACLadder]

@Chopin75 If you can identify a suspect recording on Spotify or similar I can check on my gear. I have many recordings that drove the old M7 with USB32 input nuts. Luckily they sound better on S7 and R7. But that is bad distortion if it sounds like a "fuzzy" record stylus.

Also PCM or DSD?

 

[DACLadder]

Hi, Kingwa did it again! http://www.audio-gd.com/R2R/R27/R27EN.htm

That is awesome... an R8/ M9 mashup. My headphones take some power but 9 watts at 40 ohms is insane.