Mini to Mini: Star Quaq Cable Shield as Ground?

[viix 0]

I've went to LHS to make a Mini to mini interconnect. Robert terminated for me the connections with Canare F12 Plugs. I noticed that he terminated the StarQuad cable with the 2 blue pairs of wire to right channel & 2 white pairs of the wires to the Left channel. The copper shield of the cable is used as ground.

 

This becomes an unbalanced mini to mini cable right? The sound in my setup was warmish, yet I was thinking if it was terminated with one of the white wires each to a channel with both blue to ground and the shield left unconnected, would there be any improvement or deprovement? Considering now my cables aren't shielded when the shield is used as ground. Any suggestion if I should leave it or resolder the connection?

Edited March 2, 2006 by viix

[siriuz 0]

Whats a balanced mini to mini cable?

[squalle 0]

define unbalance please

 

AFAIK, balanced connection needs + and - signal for each channel. i.e. Right+, Right-, Left+, Left-

the ground doesnt matter any more in a balanced connection

your cable, IMO is perfectly fine, it's just that it's not shielded. wat you assume might be just psychological effect

[siriuz 0]

its still shielded , as the shield is tied to ground.

just that the RF noise might "pollute" the ground further down the chain as some people claim

[squalle 0]

ermm yea

 

I just stated that it's not 100% shielded. just to avoid confusion

so still, errm no matter shielded or not, mini stereo jack or the 1/4" stereo jack, would not give you any "balanced" connection

[huangyong 0]

btw, have a doubt here?

since it's a quad cable, you join 2 wire for each channel, how to ensure that the 2 wire will conduct signal and produce coherent waveform at the end of the other side?

 

just a small question to tickle ur brain.

[1bit 0]

haha that's funny

you can try at least by making sure the two wires are of the same specification and have the same length. but for audio application in relatively short distance, i think the incoherence would be too small to be felt.

 

but anyway i might be wrong haha

this cable stuff is just too much for me

[squalle 0]

hmm

 

it depends on how sensitive ur ears are?

 

20kHz is not that high freq. so, IMO, that's not very crucial

 

what other source of "incoherence" would you think of?

easiest way is to take out each of the wires inside the star-quad, then run thru some tests?

but some people sure say something like instrument cant measure, but the ears can

[siriuz 0]

i think paralleling caps or putting caps in the signal path is a much greater evil than having dual conductors.

[neutralzz 0]

i believe the core wires are of the same specifications, thus allowing it to be used in different colored configurations.

 

in most cable applications, the shielding is use as a ground unfortunately. many ways to play around if you want to explore.

 

you could possibly use 1 white and 1 blue for ground, and 1 white for left 1 blue for right.. heh fun stuff

 

anyways trust your hearing, not solely base on specs. if it sounds right to you, and balanced, everything should be fine

[Mackie 0]

Ah.....I see there's been a huge misunderstanding regarding balanced connections. A so-called balanced cable is useless if the equipment connected on both ends are not of true-balance designs. Even some amps and cdps that sport XLR connectors are not truly balanced which in its simplest form, define a discrete balanced right and left channel. Most inexpensive consumer gears with XLR connectors actually have a common circuitry for left and right channel ie, an op-amp handling stereo channels instead of one op-amp on both right and left channel signal path.

 

Moving back to the case in concern here, any RFI pickup by a short mini-mini cable is either nil or negligible. It's imperative to maintain proper contact than placing concerns on the sinking wire in this case. A balanced cable connected to unbalanced equipment is still single-shot, ie unbalanced. View electrical connections as a system and not just part of it and in this case, the cable. The analogy is similar to terminating a power cord with UK 3-pin plug (with earthing) on one end but the earth wire is lifted on the equipemt end as it only facilitates live and neutral wires (eg, equipment with stock 2-pin power cord).

 

Balanced designs and XLR cables were first seen in the pro audio industry as long cabling runs are usually the norm and as such, RFI rejection is imperative. This technology is later introduced to consumer hifi as it also contributes to a lower noise floor for truly balanced equipment.

Edited March 2, 2006 by Mackie

[viix 0]

I see it now regarding the balanced or unbalanced thingy.

 

Okay, back to the connection, I've actually made 2 cables, 1 short 15cm mini to mini and another 1m length mini to mini cable.

I was concern about the connection with the shield as ground because of the length of the 1 metre cable. I saw the guide in headfi saying to ground the sounce end of the shield, leaving the other unterminated. While the 4 conducter star quad will be in the following config: 1 white for left, the other white for right channel and the remaining 2 blues as ground. In this case, wouldn't the shield still "pollute" the ground still since it's connected?

 

I was concern because if it was terminated with the shield as ground and 2 wires for each of the channel, I probably would have just gotten normal 2 conducter cable like the canare L2T2S instead of a star quad!!

[viix 0]

btw, have a doubt here?

since it's a quad cable, you join 2 wire for each channel, how to ensure that the 2 wire will conduct signal and produce coherent waveform at the end of the other side?

 

just a small question to tickle ur brain

 

hmm, 2 paths means lesser resistance, would it not be better for the signal?

[Mackie 0]

viix: U worry too much about nothing. The cables that you have connected as such will not result in huge pickup in RFI not unless U stay near a transmitter. Have you considered the greater wire gauge with 2 conductor wires terminated to a single contact point, much akin to 2 separate runs of speaker cables connected to one speaker (known as shotgun mode), that actually improves sound quality? It's all about compromise and priorities. Your present worry will result in xenephobia if consistent? Just joking. FWIW, I would have done the same with a star quad wire and use the sinking wire as ground. Anyhow, Robert of LHS has terminated cables for audiophiles even before the birth of this forum, he knows what he is doing.

Edited March 2, 2006 by Mackie

[viix 0]

LOL. Yeah.. I believe it's just psychological regarding the effects of RFI affecting the sound. I was wondering if I could optimise my cables to the max in it's current configuration . No point if I bought an off road car to drive on a race track or a ferrari for singapore's short roads lol!