Hey, you joke.... but what about us novices that are told to keep the speaker wires the same length! Why?
Here we have a mix of wires some 30% longer than the other and of quite a high resistance....and then there's capacity....Oh my God, my brain hurts!!!!
Then I look at my BSC circuit and it has a resistor in it with one solitary wire thats less than 0.5mm diameter.....
What?
More Gin and Tonic.....that will make it better!
Here we have a mix of wires some 30% longer than the other and of quite a high resistance....and then there's capacity....Oh my God, my brain hurts!!!!
Then I look at my BSC circuit and it has a resistor in it with one solitary wire thats less than 0.5mm diameter.....
What?
More Gin and Tonic.....that will make it better!
Bob's 1st question was what speaker... you also need to include amp in this equation. We are mostly playing with FE108ES/FE126/FE127 & CSS FR & WR driven by RH84, trioded class A EL84 PP (variant of El Cheapo with better iron), and MiniA.
We started out using Cat 5 with the 4 strips together & 4 solids together (and as many as 24 strands for speaker cable), and have slowly moved to single pairs of wires. These should be spearated. The last speaker cable shootout we did a single pair of cyro-treated PVC insulated Cat 5 wires was quite a bit better than a 4/4 section of Teflon insulated....
dave
We started out using Cat 5 with the 4 strips together & 4 solids together (and as many as 24 strands for speaker cable), and have slowly moved to single pairs of wires. These should be spearated. The last speaker cable shootout we did a single pair of cyro-treated PVC insulated Cat 5 wires was quite a bit better than a 4/4 section of Teflon insulated....
dave
From a practical standpoint, the price of PVC Cat5 is low enough that you could make up many configurations of speaker cable and not break the bank. Using an SI T-amp on CSS FR125, FE126e, and others,I've found splitting the pairs (4 wire to + and 4 wires to -) and using the original sheath to be a workable solution.Lostcause said:
westend said:
Westend, that's exactly what I did, but from now on I will split the twisted pairs into solid and stripe.
planet10 said:
Hey Dave, I'm not 100 percent sure, but I think a plenum rating is strictly for fire outgassing. It has absolutely nothing to do with electrical shielding. You may have paid extra money for nothing.
Cryo treating is interesting, though. It works wonders on steel woodworking plane blades (they stay sharp longer)
Doug
Here's an interesting link that explains some things about our little subject here:
http://www.aes.org/sections/pnw/pnwrecaps/2000/lampen/
Here's a quote from one of the paragraphs:
"Capacitance stores a charge in the cable, and is determined by the distance between conductors, and by the type of insulation (dielectric) between conductors. Signals with very high frequencies (like digital signals) want to be in low-capacitance cable, especially for long runs, otherwise the signal won't make it to the other end. Running electricity through a wire creates a magnetic field, and the ease with which the magnetic field flows through a wire encased with a dielectric depends upon the dielectric material; those qualities are measured by the Dielectric Constant (K) and the Velocity of Propagation (Vp). For direct current, a lower number is better; Vp percentages will be in (%), and for Vp, a higher number is better. The DC for air is 1; Teflon is 2.1 (70%); Polyethylene is 2.25 (66%); Polypropylene is 2 to 3 (64%); PVC is 3 to 5 (50%); rubber is 5+; chemically foamed polyethylene or Teflon is (78%); nitrogen gas-injected foamed polyethylene or Teflon is (83%). (He didn't tell us Vp for air or rubb er, or the DC for the chemical foams). Vp is relative to the speed of light (100%). CAT 5 cable, as used between computers, has a foamed dielectric; using regular microphone cable wouldn't work as well."
So what he is saying is that teflon has a K of 2.1 compared to 3 to 5 for PVC (roughly 100% better), and teflon has a Vp of 70% compared to 50% for PVC,(roughly 40% better). So teflon is clearly better for carrying electricity. Whether you can actually hear a difference or not is another story.
Well at least now I have an option of putting one cable in a vacuum or else making it with plenum rated Cat5 and leaving the other as PVC. See, no problem
.
Doug
http://www.aes.org/sections/pnw/pnwrecaps/2000/lampen/
Here's a quote from one of the paragraphs:
"Capacitance stores a charge in the cable, and is determined by the distance between conductors, and by the type of insulation (dielectric) between conductors. Signals with very high frequencies (like digital signals) want to be in low-capacitance cable, especially for long runs, otherwise the signal won't make it to the other end. Running electricity through a wire creates a magnetic field, and the ease with which the magnetic field flows through a wire encased with a dielectric depends upon the dielectric material; those qualities are measured by the Dielectric Constant (K) and the Velocity of Propagation (Vp). For direct current, a lower number is better; Vp percentages will be in (%), and for Vp, a higher number is better. The DC for air is 1; Teflon is 2.1 (70%); Polyethylene is 2.25 (66%); Polypropylene is 2 to 3 (64%); PVC is 3 to 5 (50%); rubber is 5+; chemically foamed polyethylene or Teflon is (78%); nitrogen gas-injected foamed polyethylene or Teflon is (83%). (He didn't tell us Vp for air or rubb er, or the DC for the chemical foams). Vp is relative to the speed of light (100%). CAT 5 cable, as used between computers, has a foamed dielectric; using regular microphone cable wouldn't work as well."
So what he is saying is that teflon has a K of 2.1 compared to 3 to 5 for PVC (roughly 100% better), and teflon has a Vp of 70% compared to 50% for PVC,(roughly 40% better). So teflon is clearly better for carrying electricity. Whether you can actually hear a difference or not is another story.
Well at least now I have an option of putting one cable in a vacuum or else making it with plenum rated Cat5 and leaving the other as PVC. See, no problem
.Doug
I don't know. This guy is representing a manufactuer of cable who is presenting to an engineering society. We have to assume he knows what he is talking about. Chemical engineers can do some pretty amazing things. I personally do not see why Cat5 insulation can't be foamed. There is such a thing as 'closed cell foam' and 'open cell foam.' I imagine they would use the former.
Doug
Doug
OK, I guess I need a bit of education here. PVC has twice the absorption coefficient as Teflon and therefore is twice as bad. But what is the time constant here? What is the rise time of the energy in the dielectric. Convert that to frequency and power level of the signal created by the dielectric?
Bob
Bob
Hi chaps, well I nabbed some CAT5E from work and had a go at 4 colours for + and the whites for - and hooked her up....
Oh dear...Oh dear...Where did the base go?
This stuff just sucked the life out of my TA2020 amp I'm afraid.
It was a 15' length but all that lovely tripath detail just vanished into thin air!! Even when I wind it up to full volume everything is missing.
Maybe a short run will be better?...I'll see how close I can get my setup before the wife complains!
Sorry chaps
Lee
Oh dear...Oh dear...Where did the base go?
This stuff just sucked the life out of my TA2020 amp I'm afraid.
It was a 15' length but all that lovely tripath detail just vanished into thin air!! Even when I wind it up to full volume everything is missing.
Maybe a short run will be better?...I'll see how close I can get my setup before the wife complains!
Sorry chaps
Lee
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