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I'm trying once again to gather some information on making interconnects. I've read hours of threads, folks have their opinions, but why is soldering better than, crimping, or crimping better than soldering, and what about those Cardas solderless crimpless beauties?


If anyone who works with these regularly, or has done some testing could explain why one methos is better than another, I could really use the cheerful assistance right about now. I'm swimming in indecision regarding teflon/pvc, silver/copper, twisted/parallel, shielded from RF/non-shielded for more dynamic sound, crimped/soldered with wonder solder/cardas slip ons...


Why do I like this hobby so much, I simply cannot imagine?!
 

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Diver,


I'm going to assume you've seen Chris White's DIY cable page ( http://www.bus.ucf.edu/cwhite/theater/DIYCable.htm ). These are the instructions I followed and I found them to be very easy. The cables come out great too! His method calls for crimping, and while I can't say I've compared the crimp method to the solder method, I don't know if I trust my soldering skills!
 

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Either method, if done properly, is fine. It takes a LOT more skill the soldering way. Crimpers work fine and are a lot faster to do. Make sure to give a tug on the connection afterwards. Since I bought a crimper and stripper, I've never had a poor connection.
 

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both. crimp it then solder it...
 

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Quote:
both. crimp it then solder it...
This might be okay (if unnecessary) for speaker wire, but for signal cabling it is probably not the best idea.


The problem is that the added mass of the crimped metal will require much more heat to accomplish the soldering. This can melt or otherwise damage the insulation around the center conductor. If you don’t get a short immediately, you would be more susceptible to one in the future.


Regards,

Wayne A. Pflughaupt
 

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I vote with Wayne. And here's why. I've participated in some objective testing of impedance of component video cabling using a TDR at a local manufacturer of video slot machines. One set of component cables was pretty good, pretty uniform at 75 ohm impedance from start to end of the cable. Except there were a few areas of pretty small lumps/humps. And you know what? The lumps/humps were in areas where heat shrink was applied. The person who built the cables wasn't careful enough and applied too much heat too close at the heat shrink. So this is precisely what can happen if you solder video cable connections. For video, 75 ohm impedance is a crucial spec.
 

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I don't know this for a fact, but I remember reading that is was much better to crimp than to solder.
 

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The Arizona Audiophile Society's resident video engineering guru, who has asked me not to bring his name up on the forum (oh well), the one with the three TDRs, says he feels that from an engineering standpoint the crimp is the most solid connection.
 

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â€Engineering standpoint?†As a former installer who's "done it all," so to speak, I’d say either soldering or crimping is fine from a mechanical standpoint, if properly executed. Either method can be done poorly in the hands of someone without the proper skills and/or tools. Both have their associative positives and negatives. The important thing not to do, as noted, is both.


From a sonic (or visual) standpoint – well, I’m not going there.


By the way, Steve, those “lumps and bumps†you mentioned – was that something measured, or a physical deformity of the cable (due to the poor heat shrinking)? I have to wonder why the cable was heat shrinked at all. Heat shrinking is for splicing, not termination, IMO. A well-designed connector, properly terminated, shouldn’t need heat shrink.


Regards,

Wayne A. Pflughaupt
 

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Quote:
A well-designed connector, properly terminated, shouldn’t need heat shrink.
Is is a question of necessity versus aesthetics/function? I put different colors of heat shrink at the ends of some of my cables to differentiate them (white and red for audio, yellow for video, etc.
 

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It was a 1M component cable, made by a prominent web company,

with just say an inch of heat shrink near each cable end, and in the middle, basically just for support. The "lump" was on the 75 ohm graph from the TDR, in that there was a small lump/bump each place that the heat shrink was shrunk around. Our resident engineer video guru showed us his special heat shrinker tool that doesn't get too hot and he said wouldn't casue this to happen. The cable looks fine from the outside. Its the measured impedance with a bit of a lump/bump at these three areas.
 

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Scott,
Quote:
I put different colors of heat shrink at the ends of some of my cables to differentiate them (white and red for audio, yellow for video, etc.
I was talking about using heat shrink for strain-relief purposes. Sorry for being less than clear. I use heat shrink “collars†for ID purposes, too (white for write-on labeling). No problem – just don’t overheat it, as Steve noted.


Steve,
Quote:
The "lump" was on the 75 ohm graph from the TDR...
Interesting stuff, especially being able to electronically measure specific sections of a cable.


For the record, heat shrink makes for a lousy “support.†It is fairly stiff, but also thin and will eventually crack with movement.


No strain-relief method I’ve seen is effectual when you get right down to it. If it does successfully prevent cable failure at the end of the connector barrel, it just “moves†down to the end of the strain relief.


Regards,

Wayne A. Pflughaupt
 

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Yup, a TDR hooked up to a monitor will allow you to measure impedance from start to finish of a cable. No matter how long it is!!!! I was discussing this with Joel Silver of the Imaging Science Foundation, who mentioned that even though a mill may spin the cabling at 75 ohm impedance, that often toward the end of the spool the impedance will vary more than spec, so the mill should not sell that portion of the video cable.
 

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Thanks for clarifying Wayne. Sorry I misunderstood you!
 
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