Analysis of speaker cables

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Like when cable reflections help make an amplifier break out into drive level dependent parasitic oscillations? Linear and time-invariant?

Look, I agree people should understand basic concepts first. Maybe a diy forum is not the place to get into complexities?

Not getting into complexities is not a license to spread technical nonsense. Like you just did above. But I agree people not understanding the very basics are likely the most gullible and receptive to such nonsense.
 
Like when cable reflections help make an amplifier break out into drive level dependent parasitic oscillations? Linear and time-invariant?

You either dont understand or deliberatly confuse. Probably the both. The question was: is a cable linear and time invariant. Noone asked if an amplifier cables and speakers where linear and time invariant. This is the kind of nonsense arguement I see over and over.
 
I'm impressed by the detailed models that Wayne used.
The L and C of a cable do not vary that much, but the series resistance and the parallel conductance varies significantly.
I'll try to implement this in my model just as well as using the 4.8R 100uH load as he did and see what this does to the very low capacity Valhalla cable.

Hans
 
Didn't we do a 300 element lumped line to demonstrate the point of convergence of the lumped and TL solutions? It was all posted here. This was with ideal loads, I can't imagine a simulated speaker would be anything but a mess with the 3000pF/m cable loading the amp being more of an issue.

Yes, same thing over and over and over...did I mention over??? Again.

Perhaps I revisited this forum too early.

Jn
 
Cable reflections are NOT a factor at the Audio frequencies and cable lengths involved.

In general, cable discussions in this Forum remind me of heated and prolonged Byzantine discussions on how many angels could sit on top of a pin and similar nonsense.

Oh, all parts involved could quote tons of opinions on their particular side, **oozing** "Authority".
So what?

WASTE of time.
Millions of people connect speakers to amps with basically 16/18 ga zip cord, respected manufacturers suggest nothing else, only 0.00001% of Audio users waste time on such foolishness.
 
It is NOT about cable reflections. Yes, they do occur, yes they can be measured, yes the RF characteristic impedance is a concern. But not for the simplistic reasons you think of (correct me if I misunderstand you).

The characteristic impedance defines the per foot inductance and capacitance of a cable.

The most important characteristic entity is the energy storage per foot for the cable.

When the load Z matches the line Z, the energy storage within the cable will be a minima.

Sometime in the next decade or two, that will be considered.

Till then, TTFN.

Jn
 
I don't see any measurements gentlemen.

I would propose using a VNA and in the calibration routine (open, short, load) the load be complex (like a speaker, instead of the 50R Caddock I use). Run the basic calibration routine with your Monster cable or 16Ga zip wire, one to the reference channel, the other same length to the measurement channel and call that cable-A. Now you've got impedance in its real and complex features.

Run the test again with cable-A into the reference channel, and and equal length run of Cable-B into the "test" channel of the VNA.
 

PRR

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...most important characteristic entity is the energy storage per foot for the cable...

Per cable, not per foot.

Moving the amp closer is usually an option. Why do we do this so rarely?

There is REAL energy storage in the loudspeaker's moving mass. A typical woofer is hundreds of uFd on the electric side. Balance that against the capacitance of cable. Even assuming a super-hi-C cable it takes hundreds of miles to approach the effective C of 50 grams of copper in a few KG of magnet.
 
It’s funny how a subject concerning quality of sound can result in so many emotions, just like with 44.1/16 and 192/24.
Very well possible that this speaker thing all has been discussed in the past, but not everybody joined at that moment.

I found the Cyril Bateman paper quite interesting, reading that an amp can get destroyed with the wrong combination of cable(length) and LS.
And at the same time that a very simple solution could be found with a 100R resistor par. to a RC combination.
I have repaired amps with blown end stages despite their overload protection and I always wondered how that was possible.

My wife is perfectly happy with her mono Wifi radio that she carries with her to all the places in house.
She doesn’t even want to listen to the same content through my ESL’s because she prefers the sound of her radio :D
So who cares about LS cables ?
As mentioned before, to me it’s still black magic.
Maybe JN has a point with energy stored in the cable, who knows, but I haven’t yet got my head around it.

Hans
 
I don't see any measurements gentlemen.

I would propose using a VNA and in the calibration routine (open, short, load) the load be complex (like a speaker, instead of the 50R Caddock I use). Run the basic calibration routine with your Monster cable or 16Ga zip wire, one to the reference channel, the other same length to the measurement channel and call that cable-A. Now you've got impedance in its real and complex features.

Run the test again with cable-A into the reference channel, and and equal length run of Cable-B into the "test" channel of the VNA.

Because it’s a hobby and out of curiousity, I’m certainly going to measure the whole lot, open, short and load with my VNA.
But what do you mean with measurement channel and reference channel ?

Hans
 
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