Four or two conductor mic cable?

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I'd like to make my own cables. Looking through the Full Compass catalog, they have two and four conductor cable. There's the further distinction of "for portable use" and "permanent install." What the hell is all this?

I copied the Recording Website article on making cable, to which everyone here always posts links, and it says use two conductor. I'm pretty certain that's all I need FOR NOW. But if I'm buying 100 ft. of this stuff, I'd hate to need four conductor cable for something in the future and not be able to use the bulk I'm about to purchase. The latest Tape Op has a story on converting the MXL-2001 to tube mic. It makes a special point to say get a four conductor cable, so I'm inferring it has something to do with tube mics needing extra power.

Also, is this cable(balanced mic cable) what you use for balanced line level signals, specifically, preamp to sound card breakout box?

I've learned the hard way, Hosa reaaaally does suck.
 
ap - quad cables are superior - period, for any microphone or line level balanced audio.
Takes a little time to solder, but so what? Believe me, its well worth the effort.
Also - XLR's with a metal core are simply better than the plastic versions. A bit more money, but again, well worth it.

Check out the website of the manufacturer I use here http://www.gepco.com/products/cable/microphone/quadstar.htm
and then send my rep a request for a price by email : chris_lordots@gepco.com or phone him at 1-800-966-0069

Tell Chris that Sjoko from NGS Productions told you to go to him, and he'll give you a good price. They also stock Neutrix, so you can ask him to quote for that as well.
 
On the "portable cable" versus "permanent install" front: that's usually a function of the shielding and jacket material. Portable cable will have a braid or spiral wrap shield, possibly with a conductive textile underlayer as well. It'll probably also have a neoprene or EPDM rubber jacket. Result: more flexible, less "memory effect", lower handling noise, larger diameter to handle being stepped on and rolled over by pianos.

Permanent install cable will usually have a foil shield and a thinner-but-stiffer PVC jacket, which is less desirable for uses in which the cable will be flexed a lot. However, it strips easily (very important when you're terminating 500 runs of it to a rack!), and is *compact* and easy to bundle into permanent, set-and-forget treetrunk-sized wads o' wire- the sort of thing you see behind the board/rack, and under the floor, in pro studios.

If you are making permanent interconnect (like connecting up bazillions of points in a rack of outboard gear and patchbays), a roll of miniature foil-shielded permanent install cable can be your best friend. However, for any cable that's going to get flexed, coiled, uncoiled, soaked in beer, and munged around, you want portable cordage.

I'm now solidly with Sjoko on the quad cable issue for critical mic cables. I still primarily use 2-conductor foil shielded stuff for *line level* interconnect in my racks, but the extra noise rejection of the StarQuad arrangement for microphones has proved itself out in my room.

Sounds like the tube mic conversion that you're talking about needs the extra conductors for power supply use, though. I haven't seen the tapeop article, but you may be using the other two conductors to run the capsule bias, plate voltage, or filament supply to the mic- in which case you won't get the added advantage of the quad layout. But it'll still work well when wired as quad for other mic uses.

In short: buying a couple hundred feet of good quad mic cable makes perfect sense, and is something that everyone should do. Lay in the wire, and an assortment of connectors, and you'll never be more than 10 minutes away from having whatever wierdball cable the occasion calls for. Check out that link Sjoko provided, or look at http://www.markertek.com and/or http://www.mouser.com for Gepco, Canare, Mogami, Belden, or any of the other wire vendors. It's a commodity: shop and compare!
 
Hey guys. Thanks for the responses, and sorry my slow response- been pretty busy lately.

Sjoko, I called Gepco and Chris was on vacation but another guy gave me what appears to be great price, at least compared to Full Compass, on "Star Quad?" cable. I hate calling for prices though. Catalogs and websites w/o prices annoy the hell out of me. Full Compass is the same way.

Skippy, extra thanks for the thorough, as usual, explanation. Is it safe to infer from your statements that the main advantage of quad is noise rejection(usually not a problem for me) and not necessarily sound quality in general?



Gepco has switchcraft and Neutrik connectors. Any opinions on one or the other? Does it matter? I have bought Neutrik 1/4" TS before for guitar cable and was a little disappointed since there're so damned big compared to the usual guitar cable connectors and look funny. They work fine, though.
 
Ditto on the Neutrik connectors. They are so easy to work with, and their strain reliefs are so much nicer than those on the old Switchcraft connectors... Having that clutch-style strain relief on 1/4" plugs is worth having them be a little larger and kind of odd-shaped!

I'm not able to perceive any sonic advantage for quad with respect to a high-quality 2-conductor mic cable, other than the noise floor. In my opinion, quad's great advantage is in noise immunity. I very much like using quad cable for low-level mic use, especially with the quiet, acoustic music I commonly work with: the noise floor is very important to me. For remote use, it also offers a bit of redundancy (you can have a failure of one conductor and not have the whole cable become useless- just noisier...).This makes up for some of its disadvantages in terms of physical size and increased capacitance (don't use quad for high impedance sources, like guitars, unless you specifically _want_ to roll off the high end for some reason...).

Everything has its perfect application, and the quad is _primarily_ useful for low-Z, low-level mic lines, IMNSHO. You certainly *can* use it for line-level work as well, but I have some qualms about whether the bang for the buck is there (unless, of course, you have a difficult environment: e.g., SCR dimmers, a TIG welding shop, and/or a 50kW AM transmitter next door)... Other than cost and capacitance, the big disadvantage is size: if I'd wired my rack with the quad portable cordage I used for mic lines, the bundle would be about 6" in diameter....

However, having said that, I did just lay in 100' of Mogami 2799 miniature spiral-shield quad console cable, which is only .126" OD, and is just _righteous_ for rack wiring... Whenever I finally use up the last of my 1000-foot roll of Belden foil-shielded pair, I might just end up switching over to quad for fixed line level signals as well. Guess I can still learn some new tricks.

A little more technical info on quad: http://www.canare.com/starquad.html
 
Good comments skippy - check out the spec on this cable:
http://www.zaolla.com
Amazing specs. I was unaware of this stuff until I was asked to test it by their US sales director a couple of weeks ago. Tried all their cable against moggy, monster, gepco and 2 others, including some blind listening tests, where I picked out the zaolla every time, for every kind of cable, often after just a couple of seconds listening --- that is how BIG the difference was between zaolla and the others. I started these tests thinking that it would be very difficult to get an audible difference between cables as high quality as monster and moggy. WOW.
The biggest difference was caused by their DCR cable, second biggest difference by their mic cable. All very clear and immediate changes, sounding louder and better.
Expensive - very expensive, but well worth it for those critical connections.
 
Hmm. Well. if you could hear it, then by all means follow your ears.

However, I have been through the silver-conductor/Litz-wire/skin-effect wars before, and my results weren't particularly striking. One thing that very definitely worries me: you said "louder". Well, you almost certainly know this already- but there's a psychoacoustic effect at work there that is much beloved of every audio marketer: set up your demo so that your product is a couple dB louder, and people will pick it every time.

The bad news is that if you have a very low-loss cable (as this very likely is), you might indeed get a higher overall level out of it- but there might actually be no measurable *qualitative* difference (in terms of frequency or phase response). And the level issue is nearly impossible to overcome, even for someone who is a skilled and vastly experienced listener such as yourself: that's been documented many times over. If it's louder, it will somehow sound "better". The question would be whether there was a substantive difference when listening *at the exact same levels*.

I'm absolutely not trying to pick a fight here: whenever I get the chance, I'll you can bet I _will_ listen to some of this stuff, and you should certainly use it in good health if it pleases you. But until it makes it through a double-blind test (with the final levels very carefully calibrated to be identical between samples), I'll give it a miss. I'll be skeptically putting my scant funds elsewhere: cheaper wire, but better hardware to drive it with.

I have great respect for your experience, but I'm a *very* skeptical bastard, as a result of some unpleasant experience in my original studio life. It took me a long time to believe that there was a qualitative advantage for quad cables: but there is, and it can be *measured* and also easily heard. Silver-conductor cables, on the other hand, are going to have a long way to go with me: they have a major, *major* snake-oil stigma to overcome, after the Kimber Cable and Silver Audio audiophile marketing efforts that are at best complete pseudoscience.

An example- from the Silver Audio web page: "Our standard line level cables are of the 'nude' (unshielded) style, which has generally been perceived to sound 'faster' and less 'colored' than conventional fully shielded cables."

Generally perceived? Indeed.

Sigh. When it comes to this stuff, I guess that I don't mind being the guy who just can't hear it. Saves me a lot of money... Interesting info, though- thanks for the link!
 
Nothing - at all - wrong with being sceptical skippy.
I think I ought to explain one thing about our testing. My company gets send a lot of high end recording gear for testing, digital as well as analogue, its part of the service we offer. We provide an independent verification, and data, in whatever form required. The reason we get send gear is because of our ability to test to high degrees of accuracy in a highly calibrated environment first, second because all out testing is also verified by the most important thing - ears. Therefore, when I mention testing in my post, my comments are based on fact, not preference, even though in most cases I have to stay light on technical detail for obvious reasons, as there are only a few companies, like for instance Lucid, who have no objections to technical data being released.
 
Star Quad Question

So, I have some StarQuad and Neutrik TRS connectors. Do I combine the two white wires and connect to the tip, combine the two blue wires together and connect to the ring? Also, I've been told the ground shield should only be connected to the TRS plug on one end of the cable. Is that true, and if so, why? And does it matter what end goes to the source?
 
On the soldering: yes. the two whites go to tip/pin 2, the two blues go to ring/pin3.

On the shielding: the answer is "it depends". On mic level signals, the shield always gets connected at both ends. On line level signals, it depends on the overall grounding scheme you have in place for your rig. This is called "telescoping the shield", and it is an invaluable technique for preventing and/or curing ground loops. If you are going to telescope the shield, you generally want it connected at the end that goes to the input of a box, and floated at the end that connects to the output of a box. This has the effect of extending the chassis of the box with the input over the wire to the box with the output, which *usually* leads to the best noise immunity.

But shield telescoping, and grounding design, is a lot more complex than a simple rule of thumb like "always float the output connector" can cover. Some equipment handles signal ground and chassis ground incorrectly, some electronically-balanced inputs and outputs simply won't *work* with floated grounds (oh, for the days when everything went to a transformer, and came from one, and life was simple!).

In short: it really depends. When in doubt, connect the shield on both ends (unless you have a complete system grounding scheme in mind), and chase the ground loops out later. For more information, check here:

http://www.rane.com/pdf/note110.pdf
http://www.jensentransformers.com/an/an003.pdf
http://www.hut.fi/Misc/Electronics/docs/groundloop/index.html
http://www.yamaha.com/ycaservice/techdocs/Sound/ground/ground.htm

You'll find that some of the resources differ: in fact, in several places they'll contradict one another. In practice, grounding system design is still a bit of a black art.
 
In my opinion all cabling should be wired as intended - the way it was designed.
Grounding problems should be addressed at the appropriate source, not within a cable.
I do have some cables with the grounds lifted - CLEARLY MARKED - and these are for use only in the case clients bring their own equipment into the studio, and a grounding problem becomes apparent. Even in that case, its better to fix the problem at the source, time permitting.
As I used to travel extensively between studios all over the place, I can assure you my life would have been a lot easier had everyone conformed to the standard, rather than invented their own methods of wiring / grounding.
 
Skippy and sjoko2,

Thanks for the great advice--and for the links, skippy.
 
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