Let’s forget nonsense about reflections at audio frequencies and concentrate on frequency response. Increased characteristic impedance is not the reason for the signal attenuation at the high frequencies - increased inductance is. Same attenuation can be achieved by increasing capacitance. Higher dielectric constant insulation (same geometry) will increase capacitance, but inductance will stay the same. That way we will get bigger attenuation at high frequencies at lower characteristic impedance. Finding correlation between characteristic impedance and frequency response is pretty much like saying that tattoos are causing motorcycle accidents. Correlation, a very dangerous tool, assumes that if B happens when A happens, then A has to be causing B. It completely ignores the fact that both can be caused by C. In our case increase in characteristic impedance and increased attenuation at high frequencies were both caused by increased inductance.
*WHITE PAPER* The Sound of Music - How & Why the Speaker Cable Matters
G'DAY
I’ve spent a sizeable amount of the last year putting together this white paper: The Sound of Music and Error in Your Speaker Cables
Yes, I’ve done it for all the naysayers but mainly for all the cable advocates that know how you connect your separates determines the level of accuracy you can part from your system.
I’ve often theorized what is happening but now, here is some proof of what we are indeed hearing in speaker cables caused by the mismatch between the characteristic impedance of the speaker cable and the loudspeaker impedance.
I’ve included the circuit so you can build and test this out for yourselves.
Let the fun begin
Max Townshend
Townshend Audio
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- 146 posts total
The only way to get a square wave out is to match the cable impedance to the load impedance. This is a standard way of determining the characteristic impedance of unknown coax cable. The trick was shown to me when I was working on the ill-fated Blue Streak Rocket development at the Weapons Research Establishment in Adelaide in the early 60s. See my videos Geometry Matters on youtube. Max |
Audio2design is suggesting that transmission line theory does not apply at low frequencies. Well, it does, even at DC. see https://www.youtube.com/watch?v=ozeYaikI11g&t=136s And at 50/60Hz bigtime. Max |
How many square waves do we experience in audio at 10KHz. The correct answer would be 0. That has a fundamental sine-wave component at 10Khz, and every single harmonic is inaudible. It is a meaningless test. Cool, what does Rocket Development have to do with understanding electrical theory and transmission lines? townshend-audio OP303 posts11-22-2020 9:53amThe only way to get a square wave out is to match the cable impedance to the load impedance. This is a standard way of determining the characteristic impedance of unknown coax cable. The trick was shown to me when I was working on the ill-fated Blue Streak Rocket development at the Weapons Research Establishment in Adelaide in the early 60s. |
- 146 posts total