line noise increase by 500% becasue of... bad cabling?

[MrWizard6600]

yeah just... I'm really tired, maybe I'll elaborate more later, but fundimentally just a standard "HD" (8 channel so-called 24bit sound) azalia audio chipset was being raided by line noise. I couldnt figure it out, I started un-installing and re-installing drivers trying to get rid of this poxy noise. Sure enough, I was using an 8ft splitter cable for some extra length, and yeah, that extra 8 fit (16 effective feet of extra copper) was enough to draw in whatever noise from whatever and give me an output sound which had a noise distinguishable over pearl jam, and my (AC 12cm L) case fans.

Kinda like looking for your glasses everywhere but on your own head.

If I'm really feeling energetic I might take a look at this under an o-scope to see if I can measure the difference in noise...

 

[obobski]

because obviously all cables that don't cost thousands of dollars are just "A big antenna", seriously unless you were using some unshielded crap, please don't start this racket again (and please just don't even go there regarding 24-bit....the math will....blow your mind)

 

[Audiochris]

If that 8 foot splitter was only being used to get you some extra length and the other side was left unterminated, that is a huge avenue for induction and noise will most likely occur regardless of the cable quality.

 

[Hamish Campbell]

Hasn't it been established that "cable quality" beyond basic speaker cable is pretty much a myth anyway? I remember seeing some study somewhere that did double blind testing, pitting things like rusted coat hanger wire against thousand dollar speaker cable and even the most obsessive audiophiles couldn't tell the difference.

 

[obobski]

If that 8 foot splitter was only being used to get you some extra length and the other side was left unterminated, that is a huge avenue for induction and noise will most likely occur regardless of the cable quality.

why would you wire something like that?

Hasn't it been established that "cable quality" beyond basic speaker cable is pretty much a myth anyway? I remember seeing some study somewhere that did double blind testing, pitting things like rusted coat hanger wire against thousand dollar speaker cable and even the most obsessive audiophiles couldn't tell the difference.

except when you get them on a forum, and then its "a dramatic night and day difference that will define your system's sound"

 

[bobdole369]

Yup, likely common mode interference.

Your unterminated connections acted as a big antenna and brought back stuff on the ground side, which your amplifier amplified. Very common.

 

[Audiochris]

why would you wire something like that?

I wouldn't wire anything like that but the following statement by the original poster indicates that's what he may have done.

Sure enough, I was using an 8ft splitter cable for some extra length, and yeah, that extra 8 fit (16 effective feet of extra copper) was enough to draw in whatever noise from whatever and give me an output sound which had a noise distinguishable over pearl jam, and my (AC 12cm L) case fans.

 

[MrWizard6600]

because obviously all cables that don't cost thousands of dollars are just "A big antenna", seriously unless you were using some unshielded crap, please don't start this racket again (and please just don't even go there regarding 24-bit....the math will....blow your mind)

I don't know how well shielded it is I havnt cut the cable up to find out, but its reasonably thick and thus I just assumed had a good hunk of copper in it. And no, the math wont blow my mind. I know my way around sampling theorem. I'll start whatever racket I feel like starting .

I've called the HDMI cabling industry the one of the biggest scams in consumer history. The idea of gold-plated gas-injected free-range copper from only the finest quality mines being used in HDMI cabling is totally absurd. Its way cheaper to use your standard cheap HDMI cabling and, if the signal cant make it to your ouput, impliment some bloody yes gates. The need for "high quality" anolog signals somehow infaultrated binary...

But even in analog electronics resistance is just resistance and all it does is lower your total volume. "super low resistance!" cabling in audio is just as big a scam. The only issue with sound quality is noise, which can be solved through some half decent shielding, which this damned cable doesn't have.

If that 8 foot splitter was only being used to get you some extra length and the other side was left unterminated, that is a huge avenue for induction and noise will most likely occur regardless of the cable quality.

Yup, likely common mode interference.

Your unterminated connections acted as a big antenna and brought back stuff on the ground side, which your amplifier amplified. Very common.

Exactly my point, an analogy I typed up and then erased when I made my first post was that its like a guy looking for his glasses everywhere but on his own head. I don't have an audiophiles setup --open air headphones with a fair bit of competeting ambient sounds, but the noise on my line had never gotten loud enough that I could hear it over my 12cm fans, until I introduced that cable.

I wouldn't wire anything like that but the following statement by the original poster indicates that's what he may have done.

originally I had the other end plugged into a cheap pair of speakers, then the speakers dissapeared (they really were cheap), and that cable was just being used for extension, I'd even forgotten that It was a splitter until I looked at it the other day.

 

[MrWizard6600]

awww H doesn't retroactively update signature changes? nuts. I thought I had a good one...

 

[keenan]

The only issue with sound quality is noise, which can be solved through some half decent shielding, which this damned cable doesn't have.

Shielding is not a cure-all, and in consumer level audio cables it's pretty much impossible to implement properly because the shield isn't brought out on the connector. Most audio cables intended for consumer use are not shielded, even good ones. Poorly implemented shielding can be worse than no shielding at all. You're adding an antenna to your signal ground.

And it's easy to build a poor line-level cable, just take some high-quality microphone cable and use that instead of cable designed for high impedance signals. You'll get noticeable high frequency rolloff. Sure the 'boutique' cables are stupid, and I agree that for most intents and purposes the Monoprice $3 cable is fine, but your generalization doesn't hold.

You're right about one thing though, low resistance cable is a joke. Resistance basically doesn't matter at all. Capacitance and inductance, maybe, but not resistance.

 

[MrWizard6600]

capacitive cabling?

and I was under the impression 90% of consumer grade cables sold were sleeved with a conductive alloy of some kind?

These sennheiser headphones I'm using run a cable thats already 10 ft long, and theres no decernable noise on them, and, as the thread title implies, when I connect that splitter, the annoyance doesn't increase 2 fold it increases 5 or 6 fold.

 

[keenan]

capacitive cabling?

and I was under the impression 90% of consumer grade cables sold were sleeved with a conductive alloy of some kind?

Any pair of two conductors with a dielectric between them has some parasitic capacitance. The way you construct them can minimize that, but usually you trade capacitance for inductance in the process. An ideal cable doesn't exist . Adding a mostly useless shield increases capacitance as well, so it's mostly avoided. I guess some cables might be built this way, or in a coax type construction with the return on the 'shield', but it's not what I've usually seen.

These sennheiser headphones I'm using run a cable thats already 10 ft long, and theres no decernable noise on them, and, as the thread title implies, when I connect that splitter, the annoyance doesn't increase 2 fold it increases 5 or 6 fold.

Headphones are low impedance, not like a line signal. They're much less susceptible to noise than a line level signal would be. I'm surprised you'd get a lot of noise with the setup you described, but it's probably more due to the long length of unterminated cable than it is the quality of the cable itself.

 

[obobski]

Shielding is not a cure-all, and in consumer level audio cables it's pretty much impossible to implement properly because the shield isn't brought out on the connector. Most audio cables intended for consumer use are not shielded, even good ones. Poorly implemented shielding can be worse than no shielding at all. You're adding an antenna to your signal ground.

And it's easy to build a poor line-level cable, just take some high-quality microphone cable and use that instead of cable designed for high impedance signals. You'll get noticeable high frequency rolloff. Sure the 'boutique' cables are stupid, and I agree that for most intents and purposes the Monoprice $3 cable is fine, but your generalization doesn't hold.

You're right about one thing though, low resistance cable is a joke. Resistance basically doesn't matter at all. Capacitance and inductance, maybe, but not resistance.

this.

capacitive cabling?

and I was under the impression 90% of consumer grade cables sold were sleeved with a conductive alloy of some kind?

These sennheiser headphones I'm using run a cable thats already 10 ft long, and theres no decernable noise on them, and, as the thread title implies, when I connect that splitter, the annoyance doesn't increase 2 fold it increases 5 or 6 fold.

yes. (lol does that answer your question?)

there is a degree of quality, but I'd look at it in terms of "functional" and "nonfunctional", some really poorly made crap won't pass a signal without interference, this would be "nonfunctional", although if it passes the signal as the signal exists, that would be "functional", a $3 monoprice cable may suit this, or it may not, really depends on the cable you actually buy

either way, the $15,000/ft Audioquest garbage is a total scam

 

[jojo69]

Gawd have I spent a lot of time trying to chase Heisenberg out of the shack

had a setup going for a while where I could image the noise and response of different audio cables

this stuff will drive you nuts, ground loops, circulating currents, common mode, oy vey.

not as bad as the time I ran into a residential outlet that was wired wrong though, somebody put the black wire on the wide slot and I completed the circuit to a correctly wired outlet that happened to be on the opposite phase with an RCA jumper, excitement I can tell ya.

+1 on BS boutique cable