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Old 11th November 2017, 12:13 PM   #12481
scottjoplin is offline scottjoplin  Wales
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Quote:
Originally Posted by VenusFly View Post
Don't know what the monster cables are made from or how they're made and I don't really care, will probably be tossing them in the bin. Might end up taking some pics before I do though.
You probably won't though because you "don't really care"
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Old 11th November 2017, 12:15 PM   #12482
gerhard is online now gerhard  Germany
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Quote:
Originally Posted by billshurv View Post
It can make a significant change to the sub-100Hz FR of the speakers. I would not recommend it for passive speakers, but for actives it seems a valid tuning method. Rod Elliot uses it. But I don't want to open the currentdrive can of worms on here
Active is a completely different game. In a previous live I did some calculations
on the artificial change of the TS parameters after Stal (with a little circle above the a,
I cannot create that on my keyboard). That involved negative amplifier output
impedance to compensate the ohmic resistance of the coil. I gave up when I noticed
that the ohmic resistance is a moving target that changes MUCH depending on the
history of applied power.

That was in 8080 technology times. With current DSP processing one could
measure that in real time and try it again.

PS
And a 8 Ohm voice coil has usually +/- 4 Ohm resistance. Compare that
to a somewhat decent cable.
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Last edited by gerhard; 11th November 2017 at 12:31 PM.
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Old 11th November 2017, 12:18 PM   #12483
scottjoplin is offline scottjoplin  Wales
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Does it matter if the current drawn from the mains varies with the signal?
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Old 11th November 2017, 12:45 PM   #12484
Charles Darwin is offline Charles Darwin  United Kingdom
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Quote:
Originally Posted by gerhard View Post
PS
And a 8 Ohm voice coil has usually +/- 4 Ohm resistance. Compare that
to a somewhat decent cable.
The vc resistance is the real part of the drivers impedance while the i part is the frequency variable part.
Why should I count that resistance twice?
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Old 11th November 2017, 12:55 PM   #12485
soongsc is offline soongsc  Taiwan
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Quote:
Originally Posted by scottjoplin View Post
Does it matter if the current drawn from the mains varies with the signal?
In reality it is pretty hard to avoid it, but I really have not measured what exactly the interaction is yet. If I can get my hands on some reasonable equipment, I would probably try.
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Old 11th November 2017, 12:59 PM   #12486
gpauk is offline gpauk  Scotland
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Quote:
Originally Posted by scottjoplin View Post
Does it matter if the current drawn from the mains varies with the signal?
Only is the power supply is sh*te and can't provide a constant output...
Like many of these things, if it's affecting the sound it's bad design, as has often been stated here...
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Old 11th November 2017, 01:01 PM   #12487
soongsc is offline soongsc  Taiwan
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I would love to see some measurements that prove this point!
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Old 11th November 2017, 01:02 PM   #12488
Max Headroom is offline Max Headroom  Australia
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Quote:
Originally Posted by DF96 View Post
Sufficiently good isolation will be provided by any competent PSU.
So, what is a "competent PSU ?.
Quote:
As I often say, cable sensitivity is a sign of poor electronic design.
Power cable sensitivity ?....what is such "poor electronic design" ?.
Quote:
Of course, with a Class B or Class D amplifier the mains current draw will vary with the music envelope but no amount of fancy cables will change that.
The final power cord from the source power (wall socket/power strip) will have variable LCR values (and other parasitic values) according to materials and construction....it is to be expected that these values will interact with the primary circuit, and through reflection the secondary circuit and according to reactivity/damping of both these two circuits.
Any non ideal cable will vary the instantaneous voltage, current and phase values according to changing current demand for a non resistive load.
All these reactive load parameters will set up excitations that may pass audibly through to the speakers.

Dan.
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Old 11th November 2017, 01:12 PM   #12489
soongsc is offline soongsc  Taiwan
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Monster Cable was one of my earlier venture into the cable changing game. For interconnects, they advertised the skin effects at various frequencies and used litz wire of three gauges to tackle the problem. Now that I think of it, you only need one single gauge and single conductor since the gauge would limit the maximum skin depth anyway while the current load is very low.
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Old 11th November 2017, 01:15 PM   #12490
scottjoplin is offline scottjoplin  Wales
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And the twin and earth in the wall doesn't?
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