Why!? Please Tell Me Why!

[Cornan]

16 minutes ago, gmgraves said:

That was much more true a hundred years ago than it is now. One thing that many audiophiles seem to not get (or purposely ignore) is that if interconnect cables and mains cables affect the sound of an audio system why do these sonic anomalies not translate into effects on other, more important electronic signals? And face the facts, my friends, audio is a rather simple signal with limited bandwidth and fairly easy to deal-with waveform complexity. Just off-hand, video is more complex, medical scanning is much more complex, the fly-by-wire systems in modern planes are much more complex, as are missile systems radar, long distance multiplexed communications, etc are all more complex. You'd think that anything that would alter the waveform (and thus the sound) of an audio signal would wreck havoc on more important, and even crucial electrical signals, but that doesn't seem to be the case. Were such things the common occurrence that audiophiles assert, I would think that aircraft would be falling out of the sky, people on life support in hospitals would be dying of unknown causes, Radar would be giving false images and aircraft would be colliding with one another in mid air because a cable caused an aircraft's blip to show-up just a soupçon from where it ought to be, etc. But no. Only audio is affected by passive pieces of coax, and the quality of the cord that goes from the wall socket to the component. 

Now, logically speaking, does any of this seem likely?  

 

I think I’m having what you’re having! Must be stronger than absinthe anyway! ?

[gmgraves]

1 hour ago, phosphorein said:

 

Years ago I read about the hype of directional cables and decided to examine the transmission of nanosecond pulses through such cables. I had a state-of-the art monitoring system at the time and could detect sub-nanosecond rise times. I looked at the directional behavior of a number of different types of cables, including a set of Audioquest interconnects which were directionally marked. The executive summary was that I saw no directional influence on transit times of the pulses through the cable (sub-nanosecond resolution), pulse shape or amplitude. If the cable is low capacitance and well constructed then in my opinion directionality in cables is bogus. Disclaimer: I cannot rule out the possibility that labs in New York behave differently than those in the rest of the universe. BTW I heard no difference either when supplying "audiophile grade" signals. 

 Directional cables are the result of a controversial build methodology. It has nothing to do with electron flow per se. Cables are generally marked with an arrow when only one end of the coaxial cable's shield is connected to the barrel on a non-balanced connector like an RCA. This is helpful if the user is practicing what is known as "Star" grounding. To do a star ground technique, all shields terminate in one spot. Generally this would be the integrated amp or preamp. No matter whether the signal is going into the termination component or going out of it, you use the directional cables in such a way that all arrows point away from the common ground point (preamp of amp). This is supposed to improve the shielding on all leads and lowers the noise floor. It is said to work because with this type of cable assembly (sometimes called quasi-balanced cable) assures that the shield carries no current because it's only connected to ground on one end.

 

[mansr]

7 minutes ago, gmgraves said:

Directional cables are the result of a controversial build methodology. It has nothing to do with electron flow per se. Cables are generally marked with an arrow when only one end of the coaxial cable's shield is connected to the barrel on a non-balanced connector like an RCA.

An Audioquest cable I took apart has two insulated conductors surrounded by a shield. The shield is connected to the RCA plug barrel at the pointy end of the arrow. The two signal wires are obviously connected in both ends. The main result of this arrangement is some nasty reflections going back and forth along the cable, even causing a resonance at a few tens of MHz.

[gmgraves]

2 minutes ago, mansr said:

An Audioquest cable I took apart has two insulated conductors surrounded by a shield. The shield is connected to the RCA plug barrel at the pointy end of the arrow. The two signal wires are obviously connected in both ends. The main result of this arrangement is some nasty reflections going back and forth along the cable, even causing a resonance at a few tens of MHz.

That's what my picture, above shows. I don't know why there should be reflections. The circuit is completed by the two internal signal wires and the shield acts as a Faraday "cage" for those two conductors and carries no current.

[mansr]

17 minutes ago, gmgraves said:

That's what my picture, above shows.

The arrow points the other direction on the AQ cable.

 

17 minutes ago, gmgraves said:

I don't know why there should be reflections. The circuit is completed by the two internal signal wires and the shield acts as a Faraday "cage" for those two conductors and carries no current.

There are reflections for the same reason they occur in any unterminated cable.

[phosphorein]

25 minutes ago, mansr said:

An Audioquest cable I took apart has two insulated conductors surrounded by a shield. The shield is connected to the RCA plug barrel at the pointy end of the arrow. The two signal wires are obviously connected in both ends. The main result of this arrangement is some nasty reflections going back and forth along the cable, even causing a resonance at a few tens of MHz.

 

Indeed, the Audioquest cable distorted the pulse (significant ringing) but the distortion was bi-directional. I don't remember there being any difference in the broadband noise level between the directions (star grounding or not).

[mansr]

Just now, phosphorein said:

Indeed, the Audioquest cable distorted the pulse (significant ringing) but the distortion was bi-directional.

Mine, to my surprise, behaved asymmetrically. That's why I took it apart.

[phosphorein]

7 minutes ago, mansr said:

Mine, to my surprise, behaved asymmetrically. That's why I took it apart.

 

Strange! Unfortunately I no longer have access to that measuring system.

[jabbr]

1 hour ago, gmgraves said:

Absinthe? Hell, any good bottle of Kentucky bourbon or single-malt scotch will do the same thing!

That would be a far better A/B/X to participate in ?

 

Nonetheless cable sound does change over the course of the listening session ?

[vmartell22]

17 hours ago, PleasantSounds said:

 

Well, the scientists have explained this. There are well documented studies that support what you are hearing.

Google expectation bias, placebo effect, McGurk effect - they explain in a scientific way what you have experienced.

 

 

Dunning-Kruger!   Our hearing may not be as good as we think it is...

 

v

[Ralf11]

2 hours ago, jabbr said:

 

 

Perhaps you aren’t understanding the subtle explanation then. It has been verified that if you burn in your cables while drinking absinthe, as the “la louche” develops, the sound mellows. It’s [brain] chemistry. The cables which are affected are connected to neurons, frequently referred to as axons. The effect is quite real. ?

\

fixed

[Ralf11]

BTW, my Dunning-Kruger interconnects are on sale now.  They have a rich mellow phaat sound and you will looooove them.

[mansr]

1 hour ago, phosphorein said:

Strange! Unfortunately I no longer have access to that measuring system.

What sort of system was that?

[phosphorein]

22 minutes ago, mansr said:

What sort of system was that?

 

Pulse sequences used a SRS DG535 generator (and assorted other pulse generators: HP and Tektronix; I don't remember the model numbers) and I had a Lecroy 500 MHZ dual channel digital scope as well a Tektronix 7912AD digital scope (picosecond rise time) for the fast stuff. The testing of the Audioquest cable was on a whim. I was at the time verifying the time resolution of an optical detection system in which I had to have sub-nanosecond resolution in the time domain and S/N sufficient to observe a transient of 10^-5 optical density units. All this in the presence of a high power, high rep rate Nd-YAG laser which was a big-time rf generator.

[marce]

3 hours ago, jabbr said:

 

 

Perhaps you aren’t understanding the subtle explanation then. It has been verified that if you burn in your cables while drinking absinthe, as the “la louche” develops, the sound mellows. It’s chemistry. The cables which are affected are connected to neurons, frequently referred to as axons. The effect is quite real. ?

From North of England will Special Brew do instead of some fancy liqueur...

[jabbr]

15 minutes ago, marce said:

From North of England will Special Brew do instead of some fancy liqueur...

 

Ah!

 

Technically these are “gins” being botanically flavored and without sugar. The Gin & Tonic in fact contains the bittering  agent “quinine” classically from Cinchona bark, and with this explanation I hope you can better understand ?

 

I find the princesses are more likely to partake in this than ale, and we need the entire sensory experience to fully appreciate the sonic changes!

 

Of course in Northern England you have your own traditions and no doubt “Special Brew” will have its own sonic signature ?

 

There are many things that can effect the sound of a cable beyond the mundane physics of electrons ?

 

[marce]

I had a few questions on cable burn in, but all have been answered with a little internet search...

http://nordost.com/blog/what-is-cable-burn-in/

[mansr]

1 hour ago, phosphorein said:

Pulse sequences used a SRS DG535 generator (and assorted other pulse generators: HP and Tektronix; I don't remember the model numbers) and I had a Lecroy 500 MHZ dual channel digital scope as well a Tektronix 7912AD digital scope (picosecond rise time) for the fast stuff. The testing of the Audioquest cable was on a whim. I was at the time verifying the time resolution of an optical detection system in which I had to have sub-nanosecond resolution in the time domain and S/N sufficient to observe a transient of 10^-5 optical density units. All this in the presence of a high power, high rep rate Nd-YAG laser which was a big-time rf generator.

I used a Tektronix MDO3054 and its built-in AFG. Not quite up to the same specs. Then again, it's not quite the same price either.

[vmartell22]

15 minutes ago, marce said:

I had a few questions on cable burn in, but all have been answered with a little internet search...

http://nordost.com/blog/what-is-cable-burn-in/

 

 

That parody site is very funny !

 

"If cables are left unused for a prolonged period of time they become stagnant"

 

that was a blast!  - like if Monty Python decided to sell cables !

 

Thnx!

 

v

[GUTB]

Everyone knows burn-in time for cables is needed. Anyone who has tested new cables know this by experiencing the phenomena. 

[pkane2001]

24 minutes ago, GUTB said:

Everyone knows burn-in time for cables is needed. Anyone who has tested new cables know this by experiencing the phenomena. 

 

Is everything ok, GUTB? You keep repeating this. Everything still neurotypical?

[gmgraves]

4 hours ago, mansr said:

The arrow points the other direction on the AQ cable.

 

I would think that the cable manufacturers would at least get together on the arrow's direction. I wrote an article about star grounding technique about 20 years ago and made those drawings. I called Monster at the time and talked to one of their engineers. He told me that the convention was that the arrow pointed away from the end where the the shield was fixed tho show the direction that all connections went, AWAY from the common grounding point. I guess it could be either way pointing at the common termination or pointing away from it. I wonder why Audioquest decided to point away from it. It seems confusing especially since I've never noticed any mention on any cable's packaging referencing the arrow or what it's for!

[gmgraves]

1 hour ago, vmartell22 said:

 

 

That parody site is very funny !

 

"If cables are left unused for a prolonged period of time they become stagnant"

 

that was a blast!  - like if Monty Python decided to sell cables !

 

Thnx!

 

v

I wonder if cable companies like Nordost actually believe the nonsense that they spout in their literature. Surely it must be a joke for them. Stagnant cables! Does Nordost claim that unused cables form a layer of algae on their jackets, or perhaps they sag into a pool of soggy morass if not used?

[gmgraves]

4 hours ago, mansr said:

The arrow points the other direction on the AQ cable.

 

There are reflections for the same reason they occur in any unterminated cable.

But in interconnects the source is a fairly low impedance, and the destination is a relatively high impedance. That should be fairly proper termination for a coaxial interconnect. 

[fas42]

9 hours ago, marce said:

No.

 

No to what?