Music Cables

[Chilly]

I've just been having an argument with tdc on facebook about a usb cable he bought for his external sound interface thinger.

Essentially my position is that since the protocol between the driver on the computer and the hardware device on the other end of the usb cable is a digital, error corrected one, there is simply no room for cable quality to affect the resulting DAC'd audio signal.

Sweet cables are required for analogue situations, clearly, and you should apply diminishing return rules when choosing, but I simply cant see how this can be anything except a scam.

Thoughts?

 

[TdC]

chilly == heretic

seriously (and the background for le Chillzor and myself talking):
I was using an A-B usb printer cable with my DAC, but because I have been promoted at workies I decidede to get myself a gift and experiment with audio stuffs at the same time. So, I bought a higher spec USB cable (ie a Furutech GT2) which is much more shielded and with better grade internal components than your average cable presumably.

I would argue that having an expensive cable for a digital source would be a massive waste of time/money, but this cable isn't too expensive to provide me with the pleasure of this experiment, and I am currently auditioning it.

My current conclusion is: more instrument detail, and a slightly better spacial placement. This is supposed to not be happening. Chilly says I have been infested with brain slugs.

 

[Ch3tan]

it's all in your head teedles. Chilly is right.

 

[Tom]

I'm what could be called an audiophile (my credentials - Roksan Xerxes, Arcam Delta 70.3, Naim Nac 42.5, 2* Velleman valve monobloc power amps, Musical Fidelity speakers), but I have to say that when it comes to cables, it's all a load of arse. So long as they're impedance matched for the equipment they're connected to, and adequately shielded and grounded, it makes no difference what you use.

You're wrong TDC, and anyone could prove it very easily by blindfolding you and asking you to tell the difference then.

 

[caLLous]

England 1 - 0 Dutchland

 

[old.user4556]

I'm what could be called an audiophile

Likewise, but I disagree; I've just upgraded to QED Silver Anniversary XT and it's opened up breathy trebles that were missing on my previous cable.

That said, those that say a £100 HDMI 1m cable gives a 'warmer, crisper image' than a £3 HDMI 1m cable off ebay gives me vast amount of mega lulz, but not as much as gold plated optical cables do.

 

[Tom]

Likewise, but I disagree; I've just upgraded to QED Silver Anniversary XT and it's opened up breathy trebles that were missing on my previous cable.

Do yourself a favour. Get down to B&Q, buy a good long length of lawnmower mains cable, and substitute your QED for that.

Because I guarantee that while wearing a blindfold, you would never, ever, be able to tell the difference.

Esoteric cables are just as bullshit as alternative medicines.

 

[old.user4556]

Well all know you're a hater Tom.

 

[Ch3tan]

Meh, I notice a difference between cheap speaker wire and better shielded speaker wire, however I'm not fool enough to spend money on the really expensive stuff.

 

[TdC]

not too sure about that Tom. I've made cables in the past, and there is something to be said about what makes up a thing.

Frankly I am surprised by the USB cable. There is not supposed to be a different sound, yet there is. You all seem to be arguing that because I know the cable is on I hear the sound differently, which may or may not be true. I will happily take a blind test, I am certainly not above that, and it's because of my will to test things that I bought this cable in the first place.

Still, I wonder: if this cable turns out to be a placebo as Tom and others argue, am I wrong to leave it on my system because it makes me experience more pleasure at listening to my music? I mean, I will happily make fun of homeopathy users and would never use such a bunch of rubbish myself, but on the other hand if it makes them (or myself) happy to do a thing, who am I to say otherwise?

 

[Tom]

When you buy a graphics card, you do so on the strength of tests - speed, quality, power consumption, compatibility. These are all measurable and the results can be independently verified. It's the same story with a television, or an amplifier, or a car. They each have their own design philosophies, they each have noticeable differences, and most people could easily tell them apart. You make your choice based on your personal preference.

A speaker cable, however, has a very simple job. It doesn't need shielding, it doesn't need to carry huge amounts of power. All it has to do is be as invisible as possible to the amplifier and speaker it connects. And to do that, it just has to be at the same impedance. That's it.

In double blind tests I've never heard of anyone ever being able to tell the difference between cable a and cable b.

Maybe you should have a chat with Peter Belt, he has some magical rainbow foil for sale. And he also believes that you can "treat" a digital audio file as it's copied to and from a USB memory stick.

 

[old.user4556]

Regarding blind testing; no problem, I could tell you the difference between my cheap QED flat cable (run under the carpet for aesthetics) and the new QED cable I've just replaced it with all day long. It was obviously better on some of my favourite test tracks.

Now, could I tell the difference between a £100 length of cable and a £1000 length of cable? I very much doubt it. There's also the argument that if you're spending £2k on an amp, £3k on a set of floorstanders and £1000 on a DAC - why would you use cheap cabling for your speaker runs?

 

[Wij]

It's a USB cable

If the cheap one was any worse at transferring data (and it is data) then you would expect corrupted files if you used it to connect to an external HD.

As long as it meets the minimum spec then the data is transferred 100% correct.

Dutchiiiiiiiiiiiiiiiiiiiiiiidiot !

 

[Zenith.UK]

It's plain physics.
Expensive cabling tends to be higher quality metal with lower oxygen content, better shielding and possibly precious metal plated contacts.
Cheap cabling is usually standard copper with no regard for oxygen content. Shielding is non-existent and the contacts are usually aluminium.

Yes, the signal going down both cable types is a digital signal. The carrier though is electricity. Lower quality metal tends to have higher resistance than purer metal, and this shows up as attenuation in the signal as the distance increases. Once the SNR of the signal drops below a certain threshold, it becomes harder for the "listening" device to distinguish the transmitted bits from random interference and that's where you start getting noticeable differences. You hear it on a low strength mobile phone call or a DAB radio. The sound becomes broken up and garbled, then cuts out altogether.

Now with HDMI cables, there is one thing to pay attention to and that is the shielding. Cheap HDMI cables are thin and flexible, but pick up any RFI nearby. This shows up on your TV image as bad pixels and "sparklies". Good quality cables (not necessarily expensive ones) have the shielding and have a far lower incidence of random pixels and sparklies. Don't buy into Monster's hype though. There's no need for that sort of stupid pricing.

USB cables aren't supposed to be used for runs longer than 5m because of a combination of signal attenuation and timing errors.

 

[Wij]

why would you use cheap cabling for your speaker runs?

To save money for nipple-clamps.

 

[old.user4556]

Now with HDMI cables, there is one thing to pay attention to and that is the shielding. Cheap HDMI cables are thin and flexible, but pick up any RFI nearby. This shows up on your TV image as bad pixels and "sparklies". Good quality cables (not necessarily expensive ones) have the shielding and have a far lower incidence of random pixels and sparklies. Don't buy into Monster's hype though. There's no need for that sort of stupid pricing.

There's the danger though; on one hand the snake oil crowd will claim to perceive benefits from one cable over another and on the other hand you have the "it's digital! it doesn't make a difference!" crowd who think HDMI cables can be as long as you like, as cheap as you like, as thin as you like because "it's digital!".

There were a spate of incidents on the AV forums where people were buying huge length HDMI cables for projectors from ebay and running into signal issues because of this.

 

[Wij]

"it's digital! it doesn't make a difference!" crowd who think HDMI cables can be as long as you like

Straw man argument alert !

 

[Tom]

Regarding blind testing; no problem, I could tell you the difference between my cheap QED flat cable (run under the carpet for aesthetics) and the new QED cable I've just replaced it with all day long. It was obviously better on some of my favourite test tracks.

Now, could I tell the difference between a £100 length of cable and a £1000 length of cable? I very much doubt it. There's also the argument that if you're spending £2k on an amp, £3k on a set of floorstanders and £1000 on a DAC - why would you use cheap cabling for your speaker runs?

Sorry but I think you're deluded. I do not believe you can reliably tell the difference between your old and new cables. I'm not trying to be insulting but it just isn't possible, because there's nothing to tell apart.

Don't believe me? Then tell me what the difference is. Tell me the electrical difference made by your new cable, compared to the circuit the old cable made. There aren't that many factors - voltage, current, resistance, capacitive reactance, inductive reactance - in other words, impedance. That's about all there is to it. Try connecting a single channel from your CD player to a digital recorder with some of your speaker cable, and then repeat the experiment with some cheaper cable. Use telephone bell wire if you like. There should be noticeable, comparable differences between the two waveforms, within the range of human hearing.

And you can spend as much as you like on individual components, just as you can spend as much as you like on a car - but if there's a difference, it should be easily measurable and always reproduceable.

 

[TdC]

what is that white fluff on your avatar Wij? semen?

that aside, yes, I agree with noise issues in digital cables like Big G describes. I have seen specs and artifacts on my telly with low quality hdmi cables, even though they seem to adhere to the hdmi spec somehow because they're allowed to be sold in shops and I have not seen them with other cables either high quality ones or equally low spec. Anyhoo, I guess the same holds true for USB cables. Like I said, I was using an A-B cable which I got with a printer, or was it a monitor, I forget, and I would swear on my cat's grave that it sounds different to this Furutech one even though it's supposedly impossible.

 

[Wij]

It's a spaff-beard yes.

 

[Chilly]

It's plain physics.
Expensive cabling tends to be higher quality metal with lower oxygen content, better shielding and possibly precious metal plated contacts.
Cheap cabling is usually standard copper with no regard for oxygen content. Shielding is non-existent and the contacts are usually aluminium.

Yes, the signal going down both cable types is a digital signal. The carrier though is electricity. Lower quality metal tends to have higher resistance than purer metal, and this shows up as attenuation in the signal as the distance increases. Once the SNR of the signal drops below a certain threshold, it becomes harder for the "listening" device to distinguish the transmitted bits from random interference and that's where you start getting noticeable differences. You hear it on a low strength mobile phone call or a DAB radio. The sound becomes broken up and garbled, then cuts out altogether.

That's nonsense. Low bitrate mobile phone calls lose quality because it's build into the protocol when the channel (ie the radio broacast network) can't push enough data to sustain optimum call quality. The codec will retarget it's quality based on available bandwidth. It's precisely the same thing with DAB radios. The codec can cope with a certain amount of missing data but not a lot.

The key difference between radio networks and cabled ones is that cables ones (for the purposes of digital audio in any sane configuration) simply never run out of bandwidth. Fine, if you use tinfoil it will suck and the communication won't work. However, when you're pushing a PCM bitstream down a wire from a computer to a hardware DAC, it will simply go totally wrong if the wrong data arrives. There's no fuzziness allowed. The driver and comms protocol involved in USB will make sure the data is sent reliably and correctly.

 

[old.user4556]

Sorry but I think you're deluded.

No Tom, you're wrong. I can hear a noticeable difference.

 

[Wij]

No Tom, you're wrong. I can hear a noticeable difference.

Double-blind tested ?

 

[Wazzerphuk]

Spaff-blindness tested?

 

[Tom]

No Tom, you're wrong. I can hear a noticeable difference.

"Yes, but I tried this homoeopathic medicine and I definitely feel better, so it really works."

 

[TdC]

tbh resistance should be the only factor causing an ear-detectable sound change, and then only maybe. depends on the length I guess. Still, I wonder at my cables: even though they're hardly super expensive, they're not exactly 10p a foot either and I find it hard to believe that a major industry is based on lies. Ah well, there's always homeopathy

 

[Embattle]

Generally no.

 

[Zenith.UK]

That's nonsense. Low bitrate mobile phone calls lose quality because it's build into the protocol when the channel (ie the radio broacast network) can't push enough data to sustain optimum call quality. The codec will retarget it's quality based on available bandwidth. It's precisely the same thing with DAB radios. The codec can cope with a certain amount of missing data but not a lot.

And why can't it push enough data? Conditions are affecting the propagation of radio signals. Maybe I shouldn't have switched between radio and cable in my example, but the basic principle is the same when it comes to digital transmission. The longer the distance, the greater the degradation of the signal. Once the signal degrades so far, you start getting errors in the bitstream and these bits of corrupted data show up either as bad pixels (on TV images) or garbled sound (on radio). The medium has a measurable effect on the signal it carries. One more example... DSL. The longer the length of copper in the line, the lower the data rate.

The key difference between radio networks and cabled ones is that cables ones (for the purposes of digital audio in any sane configuration) simply never run out of bandwidth. Fine, if you use tinfoil it will suck and the communication won't work. However, when you're pushing a PCM bitstream down a wire from a computer to a hardware DAC, it will simply go totally wrong if the wrong data arrives. There's no fuzziness allowed. The driver and comms protocol involved in USB will make sure the data is sent reliably and correctly.

This guy states it better than me.
http://www.audioholics.com/education/cables/hdmi-cable-speed
The "Digital is Digital" paragraph is what I'm getting at, but the section that follows it is good as well.

 

[Tom]

tbh resistance should be the only factor

Not when you're dealing with AC.

 

[Tuthmes]

A bite is a bite and still is written with 1's and 0's. That's all there's to know.