Topic: Two great mic cables for DIY builds

[voltronic]

Over the past year, I have started making my own mic cables, and have had great experience with the following two cable stock that I would like to pass along:

1. Mogami W2930 2-channel snake cable

Extremely flexible and low-profile, ultra-low capacitance. The very fine wires are a bit challenging to solder.

Redco link

Another member alerted me that Redco's own TGS-02 is the same stuff at lower cost without the Mogami branding and with different fill between the individual channels. I have not yet tried it myself, but the appearance and specs seem to match up.


2. Gotham GAC-3 3-wire double-shielded cable

Highly flexible, lays flat, performs great, handles very nicely.

Redco link

GS thread on GAC-3 soldering


Here are pictures of what I have made with the above cable stock.

[jerryfreak]

+T those look like great options

this is semi-unrelated but i just remembered an article from Benchmark discussing the rejection qualities of star-quad, so ill drop it here

https://benchmarkmedia.com/blogs/application_notes/116637511-the-importance-of-star-quad-microphone-cable

ive used canare's fullsized version (L4E6S), but i see that gotham offers a version as well

im not sure if the 'mini star-quad' like L4E5C offers the same rejection, but techinally if the relative geometry is the same i imagine it would  I always thought star-quad was a canare brand/trademark but now that i see gotham has a version, perhaps there is a larger standard somewhere, or maybe it is an original Canare product for which any patents have expired

wiki with more links

[fireonshakedwnstreet]

Very nice!

[EmRR]

I’ll also add I’ve used a lot of Canare, and all versions handle well with little to no coil shape memory problems.  I’ve got a lot of l4e6s that’s 25 years old and still coils/lays as it did when new.

I haven’t used the Mogami or Gotham, but both are well regarded. 

[voltronic]

+T those look like great options

this is semi-unrelated but i just remembered an article from Benchmark discussing the rejection qualities of star-quad, so ill drop it here

https://benchmarkmedia.com/blogs/application_notes/116637511-the-importance-of-star-quad-microphone-cable

ive used canare's fullsized version (L4E6S), but i see that gotham offers a version as well

im not sure if the 'mini star-quad' like L4E5C offers the same rejection, but techinally if the relative geometry is the same i imagine it would  I always thought star-quad was a canare brand/trademark but now that i see gotham has a version, perhaps there is a larger standard somewhere, or maybe it is an original Canare product for which any patents have expired

wiki with more links

Yes, I know about star-quad, and I have some long lengths of Canare SQ cable.  Star-Quad also tends to have higher capacitance, though this won't really come into play until you have fairly long runs.
http://audiosystemsgroup.com/CableCapacitance.pdf

I purposely went with GAC-3 rather than GAC-4 because GAC-3 already has outstanding noise rejection, and I never have runs of more than 50 ft or work in environments where SQ might start to have a benefit. GAC-3 is a mainstay among the classical recording people on GS Remote. Many users their praise its sound quality, reliability, and rejection of dimmer noise and other similar sources. It seems Gotham's 3-wire cable performs like many others' 4-wire cables, at least in terms of noise suppression.

GAC-4 looks great, but I don't see any benefits for what I'm doing right now. I will consider it for the future if I ever want to make a very long stereo cable like this but at far lower cost.

That Benchmark article is very informative, but they are comparing star-quad to 2-conductor + shield mic cables. GAC-3 is 3-conductor + double shield, so I doubt the performance differences will be as great. I haven't seen any other mic cable assembly outside of GAC-3 where an equal-size inner conductor along with two outer shields are all tied to pin 1.

[EmRR]

I'll have to try some of the Gotham, I had not seen those details. 

I did make a batch of Grimm TPR mic cables a few years ago, specifically for ribbon mics.  I appreciate it's dense insulation, similar to coax cable, and how that reduces cable microphonics, and I believe they tout low capacitance.  The stuff is a coiling nightmare though, you'd never use it in the field.  If it sounds any 'better' I can't tell it, not with my short studio runs. 

Wiring veer:

I also recently rewired my studio mic panel to control room runs with AES 110Ω rated wire, not really any more expensive than standard wire, and also by nature lower capacitance.   Hedging my bets that every little bit counts with ribbon mics. 

I have a bucket of budget mic cables I got for a mic splitter I built, I need to give them to some hapless young band or something.  They are a nightmare to coil also, I avoid them.  When I did comparative DIY capacitance measurements of a bunch of different types if wire, it was astonishingly high capacitance too. One interesting number I'm not entirely sure how to interpret apples to apples is 'impedance'.  Using a handheld L(inductance)C(capacitance)R(existence) meter, you get readings at choices of frequency (120Hz and 1K) along with series versus parallel measurement.  That cheap cable gave by far the lowest impedance reading of any, which suggests the cable itself presents a significant load on the signal, even with short runs.  Maybe the wire to use with zingy sounding cheap condensers! 

[voltronic]

I'll have to try some of the Gotham, I had not seen those details. 

I did make a batch of Grimm TPR mic cables a few years ago, specifically for ribbon mics.  I appreciate it's dense insulation, similar to coax cable, and how that reduces cable microphonics, and I believe they tout low capacitance.  The stuff is a coiling nightmare though, you'd never use it in the field.  If it sounds any 'better' I can't tell it, not with my short studio runs. 

Wiring veer:

I also recently rewired my studio mic panel to control room runs with AES 110Ω rated wire, not really any more expensive than standard wire, and also by nature lower capacitance.   Hedging my bets that every little bit counts with ribbon mics. 

I have heard good things about Grimm TPR, but did not know it coiled poorly. Better handling is one of the big reasons I have been switching out all of my cables.

I have never used AES 100 ohm cable before, but it's good to know the capacitance is lower.

[kleiner Rainer]

The concept of impedance is important in RF work, since you have a certain source impedance (50 Ohm, 75 Ohm, 110 Ohm) and a load of the same impedance. To avoid reflections and get a maximum transfer of power, the connection between  them should have the same impedance. Impedance matching is also important for LAN (twisted pair here) and AES/EBU digital interfaces.

Not so in audio work: you strive for minimum source and maximum load impedance since you want to transfer voltage, not power and reflections dont matter in that combination of frequency and cable length. Mics have typically 200 Ohm output, mic inputs 5 to 10 times that. The same is correct for line outputs: you strive for low source impedance and high load impedance. More important here is low capacitance and excellent shielding of the connection between them.

Determining a cable impedance is easy, if you have access to an RLC meter: Take some meters of the cable you want to measure. Keep it from conductive surfaces. Connect one end to meter, leave other (far) end open. Measure capacitance. Connect conductors at the far end. Measure Inductivity. Now the math: take the square root of the quotient of inductance and capacitance. Z=SQRT(L/C). As you can see, the length does not show up in the formula, since C and L are a property of the cable unit length.

I have used this method to check the impedance of unknown coax - once I got a nice double shielded teflon coax of unknown properties that the test revealed to be 50 Ohms - a bargain at pennies for the meter.

I found a page on the net that dives deep into the matter of interconnects in audio from an electronic point of view:

http://www.conradhoffman.com/Low_Level_ICs.htm

Hope that helps.

Greetings,
Rainer

[heathen]

Mogami W2697 is great for a smaller diameter cable.  I use it with my DPA 4061s, for example, to great effect.  Credit to ToddR for this...with chopped XLR connectors his Line Audio CM3s could be mistaken for actives of another brand (in size, at least).