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Right, where can we get a "perfect cable"?

Hi.

Likewise, where can we can a "perfecst" sound reproduction system?

An insulated wire or a cable is technically an attenuator, no matter
how "perfect" a cable could be.

Just to quote one delay example.

Waves travels at light speed in vacuum. In air, its propagation velocity drops 5%. It drops more when the wave is guided along a wire
with insulation which somewhat 'contains' the electric field.

This we call it dielectric delay. Foamed polyethylene, a common insulation material for coaxial cable for high frequency transfer, delays radio waves the least: 20% with its dielectric constant (e)being 1.55. The best next to free air.

Teflon (TFE & FEP) is next down the delay ladder: 30% (relative to vacuum) with e being 2.0. That's why Teflon has been popularly used as dielectric for audio cables.

To claim a "$1 RadioShack type Interconnect" "functions as perfectly as anyone could want" is a flat lie. Cheapie ICs as such commonly use PVC as insulaton & jacket. PVC is one of the worse delay line which drops wave propagation speed by 50% with e shot up to 4.0.

What is worse is it shows appreciable increase in dielectric constant, ie. wave speed delay, insulation leakage when operation temperatures & frequency increase. It will make such insulations not suitable for use as instrumentation cables where capacitance, characteristic impedance & leakage must be kept constant.

c-J


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  • Right, where can we get a "perfect cable"? - cheap-Jack 06:45:34 08/30/06 (0)


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