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Old 18th May 2011, 01:27 PM   #111
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Quote:
Originally Posted by janneman View Post
You wouldn't have any info or documentation about that 'someone' and what he did & found....?

jan didden
I think it may have been in Wireless World (about 5 years ago give or take a few. My memory is not good at some things). I thought it would have been known about around this forum.
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Old 18th May 2011, 02:09 PM   #112
DF96 is offline DF96  England
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Speaker cables have resistance, inductance and capacitance. The latter two are bound to change a little when the cable is moved or flexed. The capacitance will be a bit non-linear, as the cable insulation will have been chosen for reasons other than its goodness as a dielectric. Putting together Setup A in a lab so differences between speaker cables can be measured should not be too big a problem. It almost certainly would require a highish driving impedance, in order to see any effect. RF pickup may complicate things.

Setup B for listening tests will almost certainly be different from Setup A. This immediately means that transferring results from one to the other involves assumptions and extrapolations.

As I have said before more than once, if copper cable is non-linear then much of modern electronics simply cannot work, but it does. Therefore copper cable is linear. I think the same argument can be applied to good op-amps in well-designed circuits.
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Old 18th May 2011, 03:14 PM   #113
coluke is online now coluke  Italy
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The only ABX test regarding speaker cables I remember is the one Tom Nouisane did a few years ago - it's well described in his article 'Wired wisdom', which is worth reading. Needless to say, Nouisane found that - under controlled conditions - none could distinguish the expensive cables (990$) from the 18-cent-a-foot zip cord.

Never seen a (serious) test which resulted in the opposite conclusions.

L.
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Old 18th May 2011, 03:41 PM   #114
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Originally Posted by DF96 View Post
Speaker cables have resistance, inductance and capacitance. The latter two are bound to change a little when the cable is moved or flexed. The capacitance will be a bit non-linear, as the cable insulation will have been chosen for reasons other than its goodness as a dielectric. Putting together Setup A in a lab so differences between speaker cables can be measured should not be too big a problem. It almost certainly would require a highish driving impedance, in order to see any effect. RF pickup may complicate things.

Setup B for listening tests will almost certainly be different from Setup A. This immediately means that transferring results from one to the other involves assumptions and extrapolations.

As I have said before more than once, if copper cable is non-linear then much of modern electronics simply cannot work, but it does. Therefore copper cable is linear. I think the same argument can be applied to good op-amps in well-designed circuits.
Copper cable is non-linear (Does not follow ohms law!) It is not that hard to measure, see Linear Audio Vol. 1. But the level of deviation in normal use is very small.
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Old 18th May 2011, 03:56 PM   #115
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Originally Posted by coluke View Post
The only ABX test regarding speaker cables I remember is the one Tom Nouisane did a few years ago - it's well described in his article 'Wired wisdom', which is worth reading. Needless to say, Nouisane found that - under controlled conditions - none could distinguish the expensive cables (990$) from the 18-cent-a-foot zip cord.

Never seen a (serious) test which resulted in the opposite conclusions.

L.
Try measuring and listening to zip cable vs 10pr telephone cable...pretty much any amp and any speakers and the alert listener will discern a describable difference.

Eric.
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Old 18th May 2011, 04:34 PM   #116
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Who decides when that degree has been exceeded? If there is an advancement made is it rejected because it was done out of obssesiveness and not love?
No, but such advances are only detectable by instrumentation, and they're certainly not going to come from somebody who expects to be able to hear the difference.

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How was this decided? Was it democratically, or by central government mandate, perception by a single individual? Or extraterrestial being.
This was decided when blind testing years ago disclosed that many amplifiers were audibly indistinguishable once carefully matched for output volume. It's well enough established (and ignored) that nobody even bothers to do it now.

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Not many facts here, whole lot of generalisations and stereotypical views.
For a generalisation or a stereotype to stick it has to be built on consistencies. Nothing you have said so far convinces me that you don't conform.

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Another attempt to force ones viewpoint and actions after trying to discredit others experiences and findings.
This is hardly fair Craig. All I'm doing is pointing out the fact that this thread is propagandising a world view that all the evidence suggests is false-to-fact. The whole thread is predicated on the presupposition that there is a difference to be heard between opamps. Post enough threads like this and pretty soon you've got a coterie of the otherwise uninformed believing this crud.

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Why, is that your experience? It is certainly not mine.

I don't build discrete op-amps for serious audio reproduction or recording anymore, unless a design cannot be implemented without doing it that way.

They were a stage of progression from IC opamps.

Built a discrete/hybrid open loop input stage that had bandwidth and distortion that would put IC op-amps to shame. Primary objective was to use a topolgy combination that would minimise individual semiconductor and thermionic vacuum tube parasitic effects on the signal. It just so happened that the end result was something that also had extremley wide bandwidth.
Yes, It's my experience. You'll pardon me if I point out that in my experience the best way to 'minimise individual semiconductor and thermionic vacuum tube parasitic effects' is to use an IC.

You discrete opamp guys. You all think 'merda taurorum animas conturbit'.

w
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Old 18th May 2011, 04:48 PM   #117
DF96 is offline DF96  England
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Originally Posted by simon7000
Copper cable is non-linear (Does not follow ohms law!) It is not that hard to measure, see Linear Audio Vol. 1. But the level of deviation in normal use is very small.
I couldn't see anything there about copper non-linearity. OK, I accept that nothing is completely linear but copper is sufficiently linear that it can be regarded as linear for almost all practical purposes - certainly much more linear than any loudspeaker drive unit. Probably more linear than the speaker cabinet, and maybe more linear than the air in the cabinet.
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Old 18th May 2011, 04:58 PM   #118
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Oh no. Not cables.

I promise I won't post anything else rational, if we can just stay off cables.

w
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Old 18th May 2011, 05:18 PM   #119
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This reminds me of a story I heard about a Rupert Neve mixing desk.

One of Neve's clients said that his desk didn't sound right out of one of the channels. So some of Neve's engineers went sent to investigate. The engineers told Neve that they couldn't hear anything wrong with it. Neve told his engineers something along the lines that he trusted what his client was saying. Anway the engineers put a scope and sig gen on the channel and run a sweep through it. Turns out the channel did have a fault. It had a small bump in the frequency response at 70kHz but was otherwise flat. They replaced the channel and the client was happy.

This is a perfect example of some people can hear things that others cannot.
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Old 18th May 2011, 05:32 PM   #120
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This is a perfect example of some people can hear things that others cannot.
No, Craig, it's a perfect example of a story.

w
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