Any Data On Whether Cables Make a Difference?

[gfa]

Is anyone aware of hard data on the question of whether better quality cables make an audible difference? XLR, instrument and/or speaker. I know there are firmly held opinions pro & con, just wondering if there's any research on the topic. Google fails me here.

[pipedwho]

'Bad' cables should be avoided. Those are cables with shoddy soldering on the connectors, low quality cable that isn't properly shielded, connectors that are so bad that they don't mate properly with the equipment at either end, and cheap leads made using the wrong type of cable (i.e. unshielded when shielded is required, etc). Gold plating doesn't actually improve anything in most (ie. nearly all) cases.

That being said there are a number of use cases where each benefits from different cable properties and where other properties make no difference.

1. Line level interconnects (unbalanced 1/4" to 1/4") - just get good quality cable that has a decent out shield and good connectors. Any low to mid grade cable should be fine here.

2. Line level interconnects (XLR or 1/4" balanced) - get good quality shielded twisted pair. Star quad can help reject noise on long runs. Make sure connectors are good quality. Go with mid grade here, as super cheap cables tend not to be robust and you end up with crackling and other nasties when the cable or connections fatigue.

3. Electric guitar with passive magnetic pickups (1/4" unbalanced) - as per #1 above, but also look for cable with appropriately low capacitance. High capacitance causes the resonant frequency of the pickups (especially single coils) to noticeably drop and become dull. For high gain, cables that resist microphonic and static are important too. Most mid grade cables sold for guitar applications are generally good.

4. Acoustic (or electric) guitar with active pickups - as per #1. Once the signal is buffered it is far less susceptible to electrical issues. Capacitance doesn't matter (within reason), but still go for mid grade here as this type of cable takes a beating, and you're going for something robust that won't start to crackle and go intermittent on you. Any good lead from #3 above will work well in this application too.

5. Passive speaker cables - this is the age old thicker is better up to a point. If your speakers are a long distance away or are running very high power (ie. LOUD), then you want thicker cable. If it's low power (less than 10Watts) and the distance is short (ie. less than 5'), then pretty much anything will do. Note: avoid using instrument cable for this as the conductors are extremely thin and designed with different parameters in mind. Typical speaker cable will be heavier due to more copper in the wire, and usually figure-8 side by side. Speaker cables gain no benefit from being shielded or having twisted pairs.

6. Digital interconnects - anything will do here, just make sure the connectors look ok and the quality is sufficient that the cable won't fail when you need it most. Big thick cables aren't the answer here, as that just puts more pressure on the connectors to hold all the unnecessary weight.

[fazool]

I work specifically in the field of signal processing equipment for a related field.

I can absolutely attest to the importance of this in our field.

[pipedwho]

Originally Posted by fazool

I work specifically in the field of signal processing equipment for a related field.

I can absolutely attest to the importance of this in our field.

Once the frequencies come up to the point where transmission line theory comes into play, the cable is obviously very important. But, the parameters of the cable are even more important for those applications.

For typical audio applications having insane properties that don't translate to the real world is of no benefit. For example, a speaker cable that is incredibly thick compared to a normal thickness may make so little difference that you'd need an analyser with 100+dB of dynamic range to even measure the difference. Or for line level applications over short distances, as long as the shield is intact, the difference between any two cables will also require said analyser to be able to tell there is any difference. And these differences will be unnoticeable beyond the wind blowing on desk fader or EQ knob.

For ultra sensitive transducers, cables can make a big difference, with properly designed shielding (in some cases double shields), and accurately twisted pairs for perfect balance. Applications where the noise floor is insanely low and the signal is very small can be problematic if the impedances aren't properly matched (and sufficiently low). Applications with very wide bandwidth can suffer from noise leakage out of the cable. But, those cables are specced with appropriate parameters for the application. For example, CAT-5/6 ethernet cable is made to a specification, otherwise the cable may not have the efficiency for longer runs, be way more susceptible to EMI/RFI, and possibly radiate noise that affects other equipment.

The biggest problem with audio cable marketing is various parameters are crossed between different applications. eg. low impedance speaker cables, passive guitar leads, line level interconnections, digital interconnects (eg. ethernet), high frequency long distance transmission lines, balanced/unbalanced interconnects, RF transmission lines, and power transmission (eg. 132kV high tension overhead). Each of these areas have different properties and it makes no sense to start talking things like 'skin effect' for low voltage audio, 'matched impedance' for instrument and high impedance line level cables, or using terms like low resistance for guitar cables or low capacitance for speaker cables.

[Paultergeist]

Originally Posted by pipedwho

'Bad' cables should be avoided. Those are cables with shoddy soldering on the connectors, low quality cable that isn't properly shielded, connectors that are so bad that they don't mate properly with the equipment at either end, and cheap leads made using the wrong type of cable (i.e. unshielded when shielded is required, etc). Gold plating doesn't actually improve anything in most (ie. nearly all) cases.

That being said there are a number of use cases where each benefits from different cable properties and where other properties make no difference.

1. Line level interconnects (unbalanced 1/4" to 1/4") - just get good quality cable that has a decent out shield and good connectors. Any low to mid grade cable should be fine here.

2. Line level interconnects (XLR or 1/4" balanced) - get good quality shielded twisted pair. Star quad can help reject noise on long runs. Make sure connectors are good quality. Go with mid grade here, as super cheap cables tend not to be robust and you end up with crackling and other nasties when the cable or connections fatigue.

3. Electric guitar with passive magnetic pickups (1/4" unbalanced) - as per #1 above, but also look for cable with appropriately low capacitance. High capacitance causes the resonant frequency of the pickups (especially single coils) to noticeably drop and become dull. For high gain, cables that resist microphonic and static are important too. Most mid grade cables sold for guitar applications are generally good.

4. Acoustic (or electric) guitar with active pickups - as per #1. Once the signal is buffered it is far less susceptible to electrical issues. Capacitance doesn't matter (within reason), but still go for mid grade here as this type of cable takes a beating, and you're going for something robust that won't start to crackle and go intermittent on you. Any good lead from #3 above will work well in this application too.

5. Passive speaker cables - this is the age old thicker is better up to a point. If your speakers are a long distance away or are running very high power (ie. LOUD), then you want thicker cable. If it's low power (less than 10Watts) and the distance is short (ie. less than 5'), then pretty much anything will do. Note: avoid using instrument cable for this as the conductors are extremely thin and designed with different parameters in mind. Typical speaker cable will be heavier due to more copper in the wire, and usually figure-8 side by side. Speaker cables gain no benefit from being shielded or having twisted pairs.

6. Digital interconnects - anything will do here, just make sure the connectors look ok and the quality is sufficient that the cable won't fail when you need it most. Big thick cables aren't the answer here, as that just puts more pressure on the connectors to hold all the unnecessary weight.

One of the best brief write-ups I have ever read on the subject. Bravo.

[Cuki79]

http://www.ovnilab.com/articles/cables.shtml

http://zerocapcable.com/wordpress/?page_id=400


Thanks a lot pipedwho !!

For electric guitar see the links above

Note that it apply only to passive magnetic pickups (without battery)

Cuki

[gfa]

Originally Posted by pipedwho

'Bad' cables should be avoided. Those are cables with shoddy soldering on the connectors, low quality cable that isn't properly shielded, connectors that are so bad that they don't mate properly with the equipment at either end, and cheap leads made using the wrong type of cable (i.e. unshielded when shielded is required, etc). Gold plating doesn't actually improve anything in most (ie. nearly all) cases.

That being said there are a number of use cases where each benefits from different cable properties and where other properties make no difference.

1. Line level interconnects (unbalanced 1/4" to 1/4") - just get good quality cable that has a decent out shield and good connectors. Any low to mid grade cable should be fine here.

2. Line level interconnects (XLR or 1/4" balanced) - get good quality shielded twisted pair. Star quad can help reject noise on long runs. Make sure connectors are good quality. Go with mid grade here, as super cheap cables tend not to be robust and you end up with crackling and other nasties when the cable or connections fatigue.

3. Electric guitar with passive magnetic pickups (1/4" unbalanced) - as per #1 above, but also look for cable with appropriately low capacitance. High capacitance causes the resonant frequency of the pickups (especially single coils) to noticeably drop and become dull. For high gain, cables that resist microphonic and static are important too. Most mid grade cables sold for guitar applications are generally good.

4. Acoustic (or electric) guitar with active pickups - as per #1. Once the signal is buffered it is far less susceptible to electrical issues. Capacitance doesn't matter (within reason), but still go for mid grade here as this type of cable takes a beating, and you're going for something robust that won't start to crackle and go intermittent on you. Any good lead from #3 above will work well in this application too.

5. Passive speaker cables - this is the age old thicker is better up to a point. If your speakers are a long distance away or are running very high power (ie. LOUD), then you want thicker cable. If it's low power (less than 10Watts) and the distance is short (ie. less than 5'), then pretty much anything will do. Note: avoid using instrument cable for this as the conductors are extremely thin and designed with different parameters in mind. Typical speaker cable will be heavier due to more copper in the wire, and usually figure-8 side by side. Speaker cables gain no benefit from being shielded or having twisted pairs.

6. Digital interconnects - anything will do here, just make sure the connectors look ok and the quality is sufficient that the cable won't fail when you need it most. Big thick cables aren't the answer here, as that just puts more pressure on the connectors to hold all the unnecessary weight.

Thank you for this wealth of information.