Reccomendations for buying bilk dual coax, for making Insert cables

Started by PeterPan, January 18, 2015, 08:36:30 PM

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PeterPan

I'm basically wanting to make my own "insert" cables, and am having a hell of a time finding the typical cable, where you have two single conductor (with shiled) cables, molded together side by side. This is surprising when i consider that just about very stereo cable for any purpose is made from something like this.

I've found several cables with 2 conductors within the one shield. In fact Mouser.com has 1000 foot rolls of black Belden 5500FE cable (2 conductors with shield), for a reasonable $114/roll...

http://www.mouser.com/ProductDetail/Belden-Wire-Cable/5500FE-010U1000/?qs=sGAEpiMZZMv1%2f%252b2kKkGMBTXPa9DfutfG1mmwKvNVCwI%3d

But I don't think making insert cables out of two conductor coax cables would work very well, because you'd get leakage between the channels. Would everyone agree? Can anyone recommend a another reputable source that has the "side by side" type?

--Randy (PeterPan)
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... Second Star to the Right, and Straight on Till Morning!
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R.G.

R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

PeterPan

Quote from: R.G. on January 18, 2015, 09:57:59 PM
Why not buy hifi/stereo cables and cut the connectors off?

Just a matter of cost. Here's such a cable: that I could cut up, as you suggest...

http://www.americanmusical.com/Item--i-HOS-STP202-LIST

Notice the price is from over $6 to over $10. I need to make at least 50. More eventually. 

--Randy (PeterPan)
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... Second Star to the Right, and Straight on Till Morning!
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Brisance

Funny because my local electronics store only carries these stereo cables so I have to short the 2 center cores to make my mono cables.


Brisance

On a side note, the cable I buy is sold as "microphone cable", maybe it will help your search.

italianguy63

Pan--

If you want to save costs... on I-4 in Orando on the Fairbanks exit (you can see the store from I-4) is SkyCraft.  They specialize in surplus wire from factories.  Pennies on the dollar, and you will probably be able to find something that will work.  Their stock changes so you have to go in every once in a while.  But, I get my wire there.  I buy shielded 9 conductor 22ga. stranded wire for like $0.35 a foot.  Divide that by 9 when you strip it apart, and you have 9 colors of wire for box wiring...

You will be amazed by the stuff in there if you have never visited.

I've seen 2 conductor shielded in there (microphone wire), and the stiff military grade stuff too.  I have not seen the side/side, but I wasn't looking for it either.

Mark
I used to really be with it!  That is, until they changed what "it" is.  Now, I can't find it.  And, I'm scared!  --  Homer Simpson's dad

PeterPan

Quote from: Brisance on January 19, 2015, 05:55:06 AM
On a side note, the cable I buy is sold as "microphone cable", maybe it will help your search.

I have nothing right now. Long sordid tale. The complete cable I need is a little odd, which is why I'm considering making them from scratch, and that starts with buying bulk wire by the roll.

If you're interested (FYI), what I really need (if I could afford to have cables made) is 3.5MM TRS plug on one end to two right angle 1/4" phone plugs at the other. Trust me, no one makes it. I thought for a while I had a solution using a combination of existing cables and adapters. Hosa has some great right angle 1/4" phone to 1/4" RCA adapters, and lots of people make 3.5MM TRS to two male RCA plug cables. But putting multiple cables and adapters together gets pricy too, and if I ever sell my project, I'll have to supply 8 of these. I thought I had a another break when I discovered  several suppliers of the cable half on ali-express and eBay.  But what a waste of time and money that turned out to be. Let me tell you, what is being sold as "shielded" cables by most of the suppliers is a joke, and I wasted a lot of time and money ordering crap I could never use. I guess its because more people often use a 3.5MM to 1/4" RCA cable to connect an earphone jack to a sound system, and in that case the audio is high level and low impedance, so shielding wouldn't matter. But for my use it matters a lot. So like it or not, I may have to consider making my cables from scratch.

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *

PeterPan

Quote from: italianguy63 on January 19, 2015, 06:13:01 AM
Pan--

If you want to save costs... on I-4 in Orando on the Fairbanks exit (you can see the store from I-4) is SkyCraft.  

I've seen 2 conductor shielded in there (microphone wire), and the stiff military grade stuff too.  I have not seen the side/side, but I wasn't looking for it either.

Mark

Thanks Mark. Well the project I need this for is a LONG term project. I'd like to get it done but there's no immediate rush. So if you think you get there once in a blue moon please check for me. I know we're in the same state, but its still a pretty long ride for a treasure hunt. If you see anything like it and it looks like the guy has at least a couple hundred feet, let me know. 

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *

Ice-9

I recently bought a roll of Van Damme 100m cable, like the one here in the fleabay link, although I got the miniature stuff rather than the thicker mic cable. I'm in the UK but i'm sure if that's what you need you will be able to find it in your area of the world.

http://www.ebay.co.uk/itm/Van-Damme-Mic-Cable-100m-Drum-/381128856963?pt=UK_Musical_Cables_Leads_Connectors&hash=item58bd0cd583
www.stanleyfx.co.uk

Sanity: doing the same thing over and over again and expecting the same result. Mick Taylor

Please at least have 1 forum post before sending me a PM demanding something.

PeterPan

Quote from: Ice-9 on January 19, 2015, 10:04:12 AM
I recently bought a roll of Van Damme 100m cable, like the one here in the fleabay link, although I got the miniature stuff rather than the thicker mic cable. I'm in the UK but i'm sure if that's what you need you will be able to find it in your area of the world.

http://www.ebay.co.uk/itm/Van-Damme-Mic-Cable-100m-Drum-/381128856963?pt=UK_Musical_Cables_Leads_Connectors&hash=item58bd0cd583

Thanks. I did find some of that on the local USA ebay, but I don't think this would work for me. Even if the individual conductors each have their own independent shield (unusual for a mic cable), there would be no practical way to separate them into two connectors (to make my insert cables), without the end result looking terrible.   

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *

R.G.

I've often referred to this problem as "The Tyranny of Connectors and Cables".

I've done many designs where I went off to look for what connectors and cables were easily available before doing the rest of the design, having gotten burned once, as you are now being burned. It is easy to spend a lot of money on nonstandard cables and/or connectors.

It is easy and cheap to get contract manufacturers to make any cable you can think of, so long as you are willing to pay for injection molding dies for the connectors and order enough of them to make setting up a manufacturing line worthwhile. Something like $10K for dies and 10,000 cables will get you cables very cheaply indeed. But there's that "10,000" hump to get over.

Frankly, my best advice is to redesign your box so you can use standard cables. I know exactly how bitter that will taste. But clever and elegant can only survive if they can be paid for.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

GGBB

Look for SVHS/S-Video cable or RG174 dual or just dual-coaxial. Probably going to be pricey. Not sure if those would be okay for audio.
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italianguy63

Quote from: PeterPan on January 19, 2015, 10:01:18 AM
Quote from: italianguy63 on January 19, 2015, 06:13:01 AM
Pan--

If you want to save costs... on I-4 in Orando on the Fairbanks exit (you can see the store from I-4) is SkyCraft.  

I've seen 2 conductor shielded in there (microphone wire), and the stiff military grade stuff too.  I have not seen the side/side, but I wasn't looking for it either.

Mark

Thanks Mark. Well the project I need this for is a LONG term project. I'd like to get it done but there's no immediate rush. So if you think you get there once in a blue moon please check for me. I know we're in the same state, but its still a pretty long ride for a treasure hunt. If you see anything like it and it looks like the guy has at least a couple hundred feet, let me know. 

I will try to look-- I pop in on my lunch hour from time to time.  MC
I used to really be with it!  That is, until they changed what "it" is.  Now, I can't find it.  And, I'm scared!  --  Homer Simpson's dad

PeterPan

Quote from: R.G. on January 19, 2015, 11:13:45 AM

Frankly, my best advice is to redesign your box so you can use standard cables. I know exactly how bitter that will taste. But clever and elegant can only survive if they can be paid for.

Re-design is still a possibility. After all,there is no such thing as a "version 1" PCB layout that doesn't need SOME revision. But two things. First, as is sometimes the case, you get to a situation where your custom cable solution really is the best solution. So if you're a musician making something FOR musicians, its very hard to say "no" to what you believe to be the best way to go. And trust me, I'm flexible. But then the second thing is this... it should come as no surprise that the markup between cable manufacturer and retail is almost as bad as the drug companies. In my case I need 8 insert cables for each device, 16 if I went with all standard patch cords. And as it turns out, even having jumped the hoops to become an authorized distributor for at least one company (HOSA), my cost as a distributor for all the cables would add as much as 1/3 more to the overall cost of making the product. Thats a hard pill to swallow. If that ends up being the best i can do I suppose I can bite the bullet, offer the product, and hope prospective customers understand the cable cost issue. But while I'm considering all the possibilities, I probably should at least try to investigate making them myself. If it turns out I could turn out 50 cables in a days work for 1/5th the price, I owe to my future customers to go that route, or at least offer it as an option.

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *

PeterPan

Quote from: GGBB on January 19, 2015, 12:10:35 PM
Look for SVHS/S-Video cable or RG174 dual or just dual-coaxial. Probably going to be pricey. Not sure if those would be okay for audio.


I will look. I am finding a lot of very reasonably priced cable made for cable-TV or other RF usage (various "RG", or "radio grade" cables0), and some of them are in fact dual cables. Parts express has 250 foot rolls here for only $42!....

http://www.parts-express.com/wired-home-3206bf0e-dual-rg-6-u-quad-shield-coax-cable-250-ft--101-151#question/1175046

What a deal, right? But then when you get down to the details, cables like this often have aluminum shield/braid, which is pretty much impossible to solder, and would not make a good mecahnical connection to a dis-similar metal. Then, the core is usually single core copper clad steel. That's OK for RF, because most of the current sticks to the outside edge (skin effect). But its not so great for audio. And even if I could live with the higher resistance over short runs, I think they would be way too fragile. I've tried to make a few guitar cables out of solid core "RG" wire before. It was a constant problem. No matter how careful you are with soldering and strain relief, it still has too much tendency to break with even minimal repeated flexing.

Still, considering the price, it proves how inflated cable costs are. This stuff is cheap because its probably surplus from cable companies, who would NEVER stand for the usual ridiculous high cost of cables that WE DIY folks have to endure. 

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *


PeterPan

Quote from: GGBB on January 19, 2015, 01:01:06 PM
http://www.cdint.com/catalog/category/Bulk+Cable/RG174+dual

Not cheap though.

http://www.parts-express.com/cat/bulk-s-video-cable/1613

Way cheaper.

Thanks. I still don't think any "Radio Grade" offerings would work for me (see my last reply to you). But that second item you posted is (the 1613) is very interesting! I'm a little leery of those plain stranded wire shields. It can't surround the inner conductor as well as a braid would. But maybe for short runs (I only need 4-5 feet max) it would work. I'll have to do some research. maybe they'll offer to sell me a few feet to test with.

Anyone else have opinions on non-braided shield? (A whole new topic I guess)

--Randy (PeterPan)
*         *                                              *
   *                             *
... Second Star to the Right, and Straight on Till Morning!
       *                  *                  *

GGBB

Not all "radio grade" coax such as RG-174 uses aluminum braids - it is often tinned copper. The RG-174 I have (not twin) is copper stranded conductor and shield. Can't say what that is at Parts Express. The 50ohm impedance should not be a factor at audio frequencies.

I think the typical "stereo cable for any purpose" will not have braided shields, but I'm no expert. I *think* I've seen similar cables with braided shields in catalogs, but I doubt it's going to be anything but costly.

What's stopping you from just using separate "mono" cables joined at the TRS connector?
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