Moral: go right to the source.
In the times of Internet the question is "what is the source?"
Kimber Kable
So, my original question is still valid.
P.S. In regard to John's observation of his Teflon cable sounding lousy - I had a similar experience. Silver plated copper 7 conductor center wire, silver plated copper braided shield, white PTFE inner insulator, transparent PTFE (?) outer cover. It sounded 'bright' and 'thin'.. It was approximately 30 cm long strip from the input connector to the PCB inside the amplifier, soldered.
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The velocity of propagation for insulated cables is lower than most other commonly used plastics. This is important for low loss, transmission line cables like coax, etc. Here is some detail from a random search - Cable Velocity Factor | Velocity of Propagation | Coaxial Cable. The last few paragraphs speak to some of the other conversations about tradeoffs and mechanical concerns.
The triboelectric effect is interesting to consider as well. Some Teflon insulated cables can generate nano Amps of current into a high impedance load by just moving them around. High impedance in this case being in the gig ohm range. It is like the static electricity generated from a balloon rubbed on hair, just on a tiny scale. This effect is measureable and matters when looking at pA to fA level measurements in the lab. I make no claims for the comparably low impedance world of interconnects.
Moral: go right to the source.
One other possibility is that they're using something like the amorphous AF grades, which can be applied at a lower temperature, but at the cost of already-poor mechanical properties.
3M brands PTFE pellets and other fluorothermoplastic raw materials as Dyneon. This group includes PFA and FEP I've seen used in some cables. Both have a lower melting point for use with conventional plastics injection and wire insulating equipment while retaining a vp of ~2.1. These are softer than PTFE as well.
Dave
In the times of Internet the question is "what is the source?"
Their current website, where they have carefully removed all mention of Teflon.
Yes, that was a fix implemented in the early days of fashion cable, when high capacitance cable was blowing up amplifiers.
I assume soon you will be asked if you have proven this by scientific controlled double blind test with level matched at 0.01dB. If not, your conclusion will be stated as invalid
There must be at least 30 people in the listening room, best collected in the street nearby. >90% must hear and describe the difference according to Rec. ITU-R BS.1116-1, otherwise the result is invalid
That does not bother me... nor would I ask anyone here to critic anything related to sound-perception. I will go to professionals/specialists in that field.
I will state this however, the matching of levels is WAY over blown in its ability to mask anything I listen to and hear.
I suggest many do recordings in a church/hall where you can personally hear the room 'sound' (echo/reverb). And, that you monitor the recording while playing live and listen to the playing live that is being recorded. You will learn what characteristic sound the natural ambiance has in proportion to the mic picked up sound and learn the ratio in the recording... adjusted by mic type and distance/placement. And, you will learn the sound live heard so you know what an accurate recording ought to sound like in that recorded space. With your own master recording and knowing what it sounded like, live during recording,, you are in a best position to tell if and what changes the audio playback equipment and room/acoustics has on the sound.... because you were there. During playback, listen to the ambient hall sound and compare with the real experience. To recreate the room ambiance clearly is very hard to do well. The resolving power must be exceptional in many ways. And, a tenth of a dB in playback level (from spl at mic during recording) or more has no effect on your ability to tell which amp/preamp you can clearly hear that ambiance with.
This may be confusing to some who have not done their own recording and thus have no real reference for the sound they are using to judge quality/accuracy but its the best I can explain it right now.
Thx-RNMarsh
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Very nice rundown, Richard. The fact is, whether intended or not, a great deal of subtle ambience is picked up during all recording, the microphones don't know any better than not to do this,
! The pleasure with a system working well is that all this, often "unintended", information becomes very clear, it all makes sense to one's ears - and a recording that was formerly irritating to listen to, came across as quite an acoustic mess, now 'abruptly' snaps into focus - and one can leisurely, mentally wander through the sound spaces encoded in the recording, without difficulty, or stress - and find it very satisfying to do so ...If this is something your system resolves well and if it is something you listen for in a recording, then good. But if you actually want to hear how accurate that ambience is being reproduced, you wont know without being there during the recording. One should be able to say, I hear this room's sound just like when I was standing there... this is the such and such hall/building/room just from the reproduced sound.
Again, my point is that some of the requirements for an ABX test such as .1dB level matching doesn't even matter when listening to the sound itself, such as for ambiance resolving ability.
Thx-RNMarsh
[right now I am blasting a new CFA power amp and a new BenchMark DAC2 - breaking the caps etc in. But, so far the sound field reproduction is excellent]
Again, my point is that some of the requirements for an ABX test such as .1dB level matching doesn't even matter when listening to the sound itself, such as for ambiance resolving ability.
Thx-RNMarsh
[right now I am blasting a new CFA power amp and a new BenchMark DAC2 - breaking the caps etc in. But, so far the sound field reproduction is excellent]
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Yes, my comment covered that aspect, of the level matching - people probably would get frustrated with my casual approach to level -whether the replay is what it is, or up or down 20dB or so, is quite irrelevant, for me. From my POV, if that degree of change alters the quality of the sound, then the replay is 'defective' ...
With regards to ambience, if every recording opens up with a 'new' ambience - different from the one before - then to me this indicates I'm having a reasonably good chance of getting a decent replica of what the recording enviroment was like ...
Also, putting on a familiar recording on a completely unknown, other's system - which is working at a very high level - and out pops the ambience you know so well. This happened at the recent hifi show ...
With regards to ambience, if every recording opens up with a 'new' ambience - different from the one before - then to me this indicates I'm having a reasonably good chance of getting a decent replica of what the recording enviroment was like ...
Also, putting on a familiar recording on a completely unknown, other's system - which is working at a very high level - and out pops the ambience you know so well. This happened at the recent hifi show ...
There is no disagreement between us. I am sorry I was probably too sarcastic
.Anyway, when I place files for ABX test here, I MUST match them, in level, as close as possible, otherwise the critics would tear it to pieces
IET General Radio Historic Manuals will be posting a PDF of the General Radio Handbook of coaxial measurements. Its pretty accessible and has good illustrations. Microwave is NOT audio but the basics of measuring impedance and propagation of waves in cables should be helpful. I got a copy and can share. Its 30 MB so too big to post. Preferable to get from IET.
other basic info on coax and other forms of transmission and measurements from my own technical library:
Hewlett Packard's Microwave Theory and Application - prentice-hall
Microwave Transmission Design data.... by T.Moreno dover publications
Principles of Microwave Circuits... C.G.Montgomery dover publ.
Technique of Microwave measurements.... C.G.Montgomery dover publ
Introduction to Microwave Theory and Measurements ...Hughes Aircraft. A.L.Lance. McGraw-Hill
All old but maybe on the Internet of used book store. All have something to say about coax and measurements.
Last but best -> Newer book that covers it all: over 900 pages. The Electromagnetics Problem Solver. REA. new jersey.
Thx-RNMarsh
Hewlett Packard's Microwave Theory and Application - prentice-hall
Microwave Transmission Design data.... by T.Moreno dover publications
Principles of Microwave Circuits... C.G.Montgomery dover publ.
Technique of Microwave measurements.... C.G.Montgomery dover publ
Introduction to Microwave Theory and Measurements ...Hughes Aircraft. A.L.Lance. McGraw-Hill
All old but maybe on the Internet of used book store. All have something to say about coax and measurements.
Last but best -> Newer book that covers it all: over 900 pages. The Electromagnetics Problem Solver. REA. new jersey.
Thx-RNMarsh
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