Building 1/4" balanced cables

[Wannaplay]

I saw the recent post about making quality mic cables from the Canare star cable and xlr connectors. I would like to build similar cables with 1/4" TRS jacks for balanced cables between a DMP3 pre. and an Echo Mia soundcard. Does anyone know which wires connect where on the Neutrik 1/4" TRS jacks using the Canare cable? Thanks in advance.

 

[DJL]

Making balanced TRS patch cables using Canare, quad (4 conductor) cable.

First unbraid (comb out) braided shield with pointed tool (an ice pick works good, just be careful) and then twist it back together.

Then twist the blue leads together and then twist the white leads together.

Connect blue twisted lead to the Tip “Hot (+)”

Connect white twisted lead to the Ring “Cold (-)”

Connect the shield to the Sleeve “Ground”

Just remember that the longest is the ground, the middle is the ring, and the smallest is the tip.

1/4" TRS Connector..............
Tip - Hot (+)... White
Ring - Cold (-)... Blue
Sleeve – Shield...Ground

 

[acorec]

Making balanced TRS patch cables using Canare, quad (4 conductor) cable.

First unbraid (comb out) braided shield with pointed tool (an ice pick works good, just be careful) and then twist it back together.

Then twist the blue leads together and then twist the white leads together.

Connect blue twisted lead to the Tip “Hot (+)”

Connect white twisted lead to the Ring “Cold (-)”

Connect the shield to the Sleeve “Ground”

Just remember that the longest is the ground, the middle is the ring, and the smallest is the tip.

1/4" TRS Connector..............
Tip - Hot (+)... White
Ring - Cold (-)... Blue
Sleeve – Shield...Ground

I don't know where this new "quad" thing started, but, when you use two conductors in parallel for a single signal you are absolutley killing your high frequencies as well as adding substantial signal phaseing. You are creating a serious capacitor. If you use this for a balanced signal (2 signal lines) you are doubling the killing. Two twisted wires at both ends are by definition a capacitor (two conductors seperated by an insulator). The resistance of the twised together signal wires cut the resistance in half. Therefore, you now have no idea short of doing the math of where you are signal phaseing and where the high freq rolloff will occur. Hey, just my 2 cents worth, I only use a single wire for a single signal.

 

[DJL]

Two twisted wires at both ends are by definition a capacitor (two conductors seperated by an insulator).

Your right, I should of thought of that...... well, then just use one of the white wires and one of the blue wires and snip the other white and blue wires off.

 

[acorec]

Your right, I should of thought of that...... well, then just use one of the white wires and one of the blue wires and snip the other white and blue wires off.

I did some looking at specs for cable over lunch. I never really looked but, in the "quad" configuration that is specified by Canare, they have a spec of capacitance = 162 pF/m!

Checking the non-quad setup at Mogami, the listed capacitance spec = 57 pF/m. With the designed res/m and a low capacitance, the Mogami is a great cable. The phase shift and possible loss of hi freq on the "quad" cables must really suck. So, if I had the "quad" cable, I would use one conductor for each signal and wire the braided ground wire to :

Only wire one end (the end that plugs into the mic pre-amp) for mic cables. Don't wire the braid to the mic end of the cable.

Wire both ends if you use it between two units (like between pre-amp OUTS to mixer Ins.

 

[Wannaplay]

acorec:
Only wire one end (the end that plugs into the mic pre-amp) for mic cables. Don't wire the braid to the mic end of the cable.

Will this connection still be balanced?

I have 75 ft. of the Canare cable on the way with 1/4"TRS jacks and M/F XLR jacks for balanced cables and mic cables respectively. Why would Canare make this cable to use only 2 of the 4 wires for these applications?

Thanks for all the help guys.

 

[acorec]

acorec:
Only wire one end (the end that plugs into the mic pre-amp) for mic cables. Don't wire the braid to the mic end of the cable.

Will this connection still be balanced?

I have 75 ft. of the Canare cable on the way with 1/4"TRS jacks and M/F XLR jacks for balanced cables and mic cables respectively. Why would Canare make this cable to use only 2 of the 4 wires for these applications?

Thanks for all the help guys.

On the TRS jack, there should be three connection points. There are two signal connections and a ground connection. Since balanced cables have no reference to ground, the third ground connection is used for shielding. If you wire the braid wire to the mic-pre end of the cable, the braid acts as a shield against radio frequecies and other unwanted signals in the air. The braid is woven around both signal conductors and when grounded at one end, makes for a faraday pail. In other words, interference from radio signals will be shunted to ground. If you connect both ends, the braided shield will conduct current and radio noise. The cable will still be balanced. In good mic cable, there are two signal wires, one ground wire AND a braided shield. If you ONLY have two signal wires and a braided ground wire, then you have no option but to use the braided wire for ground on BOTH ends.
Just looking at Canare wire, the use and limited published specs, I think that they use this wire mostly for live use on a stage where severe interference by strong lights, bad ground loops etc. must be delt with. The two conductors are a twisted pair. If you use a twisted pair for each signal. you will have all the phaseing and rolled off high frequency problems. But, it is a small sacrifice for excellent radio/light/hum rejection. So, it is a compromise. I would not use this "quad" cable for studio work as the sheer amount of patch cables will add substantial phase shift and high freq rolloff. Mogami is best in the studio. I am only offering engineering advice and have no direct experience with eithr of these cables, but, Mogami gives quite a list of specs to be able to adequately judge the impedance/m and performance of their cable. Canare has very little info and specifically centers its product around "live" use on a stage.

Either way, good luck.

 

[Fletcher]

I don't know where this new "quad" thing started, but, when you use two conductors in parallel for a single signal you are absolutley killing your high frequencies as well as adding substantial signal phaseing.

You only have the potential for phase shift if the two wires are of unequal length... which they ain't... as for 'high end loss due to capacitance, it's nothing I've noticed since I've been using it [which is since about 1985].

However, it's RF rejection is absolutely spectacular... but if you're not in a high RF environment, then you can certainly get away with typical single pair cable.

One other thing I should mention... there is no such thing as "balanced cable"... equipment is balanced or unbalanced... wire ain't.

 

[Light]

I don't know where this new "quad" thing started, but, when you use two conductors in parallel for a single signal you are absolutley killing your high frequencies as well as adding substantial signal phaseing. You are creating a serious capacitor. If you use this for a balanced signal (2 signal lines) you are doubling the killing. Two twisted wires at both ends are by definition a capacitor (two conductors seperated by an insulator). The resistance of the twised together signal wires cut the resistance in half. Therefore, you now have no idea short of doing the math of where you are signal phaseing and where the high freq rolloff will occur. Hey, just my 2 cents worth, I only use a single wire for a single signal.

It depends on the independence of the signal. For instrument level signals (thousands of ohms) this is true. However, at lower independences, it is not an issue. Mics level signals are never much above a hundred ohms, so it is not a problem there, and line level signals are around a few hundred ohms. Again, not a problem.

I can't imagine that thousands of studios, engineers, and rental houses would be using quad if it was damaging the sound of the signal. Quad conductors for mic and line level signals are the choice of most professional engineers I know. You just don’t want to use them (or anything like them) for your guitar.


Light

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