Solid copper Cat5E Plenum w/ teflon insulation deal and findings

[dezireduser]

Ok, first time poster, but long time lurker... Just want to give back to the DIY community after you guys have helped me create really good cables, speakers, enclosures, etc.

First off:
I know a guy who is selling 100metres (330ft) of high-quality UTP Cat5E plenum cables with teflon insulation. I ordered from the guy, and I got it pre-cut in the sizes I wanted (i asked for 20% longer lengths than what I was shooting for. I think 10% longer would have been better.)

Basically, it's 328feet of cable for $30, (I think he charges $20 for 164feet (50m)). It's 24AWG solid bare copper conductor, 4 Pairs, Teflon insulation, and plenum jacket. Standard high-quality ethernet cable. Let me know if anyone is looking to get this stuff. I was too excited after building these cables, and was trying to convince myself of things I wanted to believe, I guess. :-/

D

Ok, about the findings:
Doing my own measurements, I found that I could keep the capacitance lower by doing a flat braid using the 6 wires, and keeping the plenum jacket on. The resistance and inductance were not affected noticeably. (The capacitance was greatly increased with the jacket off, though. And of course, the more cables, the higher the capacitance, and the lower the resistance.) In a blind test, I couldn't tell the difference between these cables and any of the other cables at the audio store(Kimbers, ACs, AQs, etc), but there was a noticeable difference between these cables and ones like SoundKing, Monster which were 16awg or higher. I think the thicker cables generated a cleaner sound.

So what does this all mean? Well, according to my ears, ,and those of the manager at the audioshop, we came to the conclusion that the cheap cat5 cables really do sound the same as the more expensive cables. I found it funny how the manager would not believe that it cost me around $40 to make the cables that would rival cables at 5x the cost and more.

So, if anyone is new to the cat5 cables, I would recommend that you keep that jacket on, put on a sleeve or heatshrink, and save yourself the hassle of imperceptable differences in sound. The braid pattern is probably more important, but then again you probably won't notice any difference.

Anyways, thanks so much for all the help, and I hope this will benefit someone who's looking into making some cat5s.

D

EDIT: Ok, you're right. There was a difference because the sales guy had connected the cables to different drivers. Went back, and grabbed 15 diff. brands of cables, did the test again with exact same setup. I could not tell the difference between any of the cables, save the skinny ones. And now, I think I'm imagining that too. Oh well. $30 to get all my cables made is not, and they look pretty cool too.

 

[Resident Loser]

And in the Bordeau IS a claret dept...

...Cat5 wire IS always solid core AND plenum cable IS always sheathed in PTFE(or Teflon if you prefer the name brand as opposed to the generic)...which is what gives it it's fire-retardant properties...cat-category wires DO NOT NEED ptfe, etc. to "work" correctly...

The TPI spec is and to some lesser extent the dielectric composition can be instrumental in keeping the signal intact over long distances(hundreds of feet)...and that would be the DATA signal in the mHZ range as opposed to our puny audio bandwidth...

And for anyone interested, the only real difference (aside from 24 awg vs 23 awg) between cat5 or 6 or 7 is that the manufacturing tolerances must be kept to a higher average standard over greater wire lengths, in order to assure a cohesive signal...again, important at data speeds...not so important for the average barnyard cackling that passes for "music" these days...

jimHJJ(...just an observation...)

 

[mtrycrafts]

.

However, do the same with cat5-based audio cables, and you'll hear differences in sound reproduction (nothing major, but you'll definitely be able to tell some difference). Maybe it's my ears, but I definitely hear some differences based on the design of the cable. Again, not 'good' or 'bad', just different. It's hard to explain - certain braid patterns sound cold, and others sound more warm, if that makes sense.

D

I seriously doubt the fragile nature of cat 5 with audio signals. Actually, the human ear is not a great receiver of small differences in signals, especially dynamic music signals. This is attested to all the null results from 30 years of DBT of wires, proper DBT and statistical analysis, that is.

But, if your hearing is as acute as you claim it to be, Tom Nousaine would like to test you. After all, progress in understanding audio is the goal.

 

[Mudcat]

...Cat5 wire IS always solid core AND plenum cable IS always sheathed in PTFE(or Teflon if you prefer the name brand as opposed to the generic)...which is what gives it it's fire-retardant properties...cat-category wires DO NOT NEED ptfe, etc. to "work" correctly...

Sorry, but a plenum rating does not imply that the jacket will be teflon. There are other fire retardant materials that are UL approved and cheaper.

Doing my own measurements, I found that I could keep the capacitance lower by doing a flat braid using the 6 wires, and keeping the plenum jacket on. The resistance and inductance were not affected noticeably. (The capacitance was greatly increased with the jacket off, though. And of course, the more cables, the higher the capacitance, and the lower the resistance.)

I would be interested in how you performed your measurements and what test equipment you used. In my experiments using an Instek LCR 821 meter I have found that I can get within 10% of calculated values for capacitance and within 2% for resistance.

If you use all of the wires (8) within one cable as + and all wires within another cable as -, then you'll get the best results as far as reducing the cable inherent high capacitance. However, by using all solids as +, and all stripes as -, then you'll be no better off than braiding the individual wires as Chris VanHaus popularized with his braided CAT 5. The reason for this is that Capacitance is added:

C_t=C₁+C₂+C₃+.....C_n

and all those wires in close proximity will have another added effect.

However, if the wires are used as I described above where all in one cable are + and all in another cable are -, then capacitance will be an order of magnitude lower. Resistance will remain unchanged, and Inductance will be increased, but only a couple of percentage points (10-15%).

I am making several CAT 5 braids to test and will provide more concrete info when I'm finished.

 

[mtrycrafts]

, and Inductance will be increased, but only a couple of percentage points (10-15%). .

I like the way you characterize 10-15% as a couple of percents, LOL

 

[Mudcat]

I like the way you characterize 10-15% as a couple of percents, LOL

Hopefully in the not to distant future, I'll be able to make a pair on CVH's braided CAT 5 cables and make a full comparison instead of guessing. I thought Gene did just that years ago, but I haven't found anything.

 

[runninkyle17]

I have already posted info about this particular deal. I think it was more than a month ago when I posted my post and it has had replies all the way till December 6th. We probably bought our cable from the same guy. Here is a link to my post:http://forums.audioholics.com/forums/showthread.php?t=15282

I am not trying to be rude at all, but next time you post something be sure it has not already been posted.

 

[Resident Loser]

Sorry for...

Sorry, but a plenum rating does not imply that the jacket will be teflon. There are other fire retardant materials that are UL approved and cheaper.

...what seems a mischaracterization but, while there are other proprietary, low smoke formulations such as Belden's FLAMARREST, etc. and any MPP/CMP-rated wiring can be used for plenum placement...most (if not all) seem to have conductors insulated with FEP and not PTFE...While the specs for dielectric constant, etc. are generally speaking, similar, wiring with Teflon insulation for the conductors AND Teflon sheathing would seem to be a "given", in the love-and-marriage/horse-and-carriage mode..

Since the original poster remarks of "...cat5 plenum cables with teflon insulation..." and given the above, the progression(at least in my mind) indicates a product with Teflon sheathing, hence my perhaps misguided, or at very least misleading, absolutism.

I will try to be more attentive to such "details" in the future.

jimHJJ(...nobody expects the Spanish Inquisition...)