An antidote to snake oil

[Speedskater]

FrantzM said:
For example, we tend to use thicker gauge of interconnect for subwoofer duties.

Speak for yourself.

Actually because RCA subwoofer cables tend to be longer cables, you need a coax with a heavy braided shield.

 

[beagleman]

Maybe it's the connector color.

I'm not joking.

That would be my answer also.

Regular RCA cables are Red or White (ends) to signify "Right or Left" channel.

Most sub cables tend to be Blue, purple, or black ends

Yellow is video.

 

[notsodeadlizard]

Of course, I understand everything, but why connect subwoofers to the amplifier with a coaxial RF cable?
This is not prohibited, just as the use of a regular cable is not prohibited, just as the use of a fashionable exotic fabulously expensive cable is not prohibited.
But why RF-frequency 75 ohm coax exactly?
Why not cheap shielded twisted pair (Ethernet STP) for example?
STP is beautiful and you can use single cable for the multiple audio channels, Ethernet Cat 6 cable is nearly perfect and there are even such beautiful devices:

Although.
What's the difference?
Whoever likes what, who likes coaxial, who likes a $4000 supercable, it's all the same, the main thing is to have a buzz.

 

[JayGilb]

Of course, I understand everything, but why connect subwoofers to the amplifier with a coaxial RF cable?
This is not prohibited, just as the use of a regular cable is not prohibited, just as the use of a fashionable exotic fabulously expensive cable is not prohibited.
But why RF-frequency 75 ohm coax exactly?
Why not cheap shielded twisted pair (Ethernet STP) for example?
STP is beautiful and you can use single cable for the multiple audio channels, Ethernet Cat 6 cable is nearly perfect and there are even such beautiful devices:

View attachment 294205
Although.
What's the difference?
Whoever likes what, who likes coaxial, who likes a $4000 supercable, it's all the same, the main thing is to have a buzz.

I have yet to purchase any ethernet to xlr connectors, due to not needing any interconnects at the moment, but they look interesting and have watched a few videos from Dave Ratt who sells similar items.
I have boxes of homemade cables and unless needed for a long run, usually make them out of basic 3 wire (2 conductors and a drain) with a braided shield. I stocked up when two area Radio Shack stores shut down several years ago.

 

[Speedskater]

Well a Shielded Twisted Pair is great for XLR balanced interconnects, but not so for RCA unbalanced interconnects.
Coax cables are best for RCA unbalanced interconnects. But coax cables optimized for high megahertz frequencies are a poor choice for analog audio RCA cables. A better choice is a coax with a heavy braided shield. Many if not most coax cables have a 75 Ohm impedance, sometimes unintentionally.

 

[egellings]

I recently bought a couple of 5m subwoofer cables from a chap on eBay. I found it refreshing that they arrived packaged with a full run down of the technical cable specs (electrical properties), a piece of cut cable stripped back to show the conductor and the two shields, plus some instructions on how to handle them to avoid kinks. I think they are used for telecoms data transmission.

The ‘sales pitch’ did not promise faster transients, subsonic low end , black backgrounds or earth shattering bass - just that the cable spec and construction would help minimise signal loss , interference and ground loops and my subs would play just fine!

They were £20 each.

They are 75ohm coax so for shits and giggles I tried one of these 5m cables as a digital link cables for my two devialet experts - needless to say they worked perfectly , even at 192/24.

Bear in mind that folks over at DevialetChat had issues with high end 2m foo foo AQ spdif cables causing drop outs used the same way

So I hope that this thread can be the antidote to Snake Oil - for good experiences of honest, good value, properly specified stuff that just does the job in the way that physics says it should

Excerpt from eBay listing …

No 'Hi-Fi cable-fu' or magic properties

Have you ever noticed how rarely Hi-Fi and AV cables come with any kind of specification?
There's no indication of the cable impedance, or the attenuation, its capacitance or the return loss. Often there isn't even an adequate basic description of what kind of shielding is used. What you get instead is pseudo-scientific sounding terms and vague hyperbole.
This mini coax has a full set of specifications. You'll get a copy with your cable.
Conductor 1 /0.31 +/-0.003BC - 100% plain copper
Insulation Material: Solid Natural PE
Nominal OD : 1.95 +/- 0.1 mm
Braiding 1 16/6/0.1+/-0.003TC / Nominal OD: ~ 2.45mm - tin coated copper- 91% Coverage
Braiding 2 16/6/0.1+/-0.003TC / Nominal OD: ~ 2.85mm - tin coated copper - 90% Coverage
Sheath Material : PVC / Colour : White
Min. thickness : 0.24mm / Nom. thickness : 0.30mm / Nominal OD : 3.55+/-0.1 mm
Minimum Bending Radius 20 mm single bend, 40 mm repeated bending
Voltage Test : Inner Conductor to Braiding: 5300V d.c/1min, No Breakdown
Nom. Capacitance : 67+/-2pF/m
Max. DC Conductor resistance : 236Ω/km, 20 OC
Min. DC Insulation resistance : 20,000MΩ/km
Characteristic Impedance : 75+/-4 Ω( 5MHz )
Maximum attenuation @ 100m measured at 1,000,000Hz (1MHz): 2.1dB

You'd need a course in physics to know it that is what you really needed.