Interconnect vs Speaker cable Res/Cap/Induct

[MacCali]

Good day everyone, as I am digging deeper into audio I was curious to know as looking into measurements is key on this website, I am hoping someone can tell and help me understand what has raised my curiosity.

So we have a general idea of what makes a speaker cable good when it comes to electrical properties like resistance, capacitance, and inductance. How come a lot of interconnect cables have so much higher readings?

Is it strictly based on conductor size? that's the only thing I can assume. The cables inside an interconnect dont tend to be 12 awg. Does it simply just come down to this principle?

Is it bad because it's much higher? I do not understand the precise difference between a signal coming from a dac into an amp vs exiting an amplifier going to a speaker. Frankly it seems like the same concept.

I am not electric engineer or honestly even have a full grasp on the exact definition of the meanings, I am not sure if my previous statement is a rational comparison or if anything I said is accurate. But I find it really odd that some of these extremely expensive cables which do publish measurements on their products and it being so much worse. I mean can you not turn a speaker cable into an RCA or XLR cable?

Thanks for reading and appreciate all responses.

 

[kongwee]

Shielded or twisted pair or quad core. No straight wire.

 

[Speedskater]

Circuit load impedance has a lot to do with the impact of cable resistance, capacitance, and inductance.
Loudspeaker load impedance might be about 8 Ohms, while an analog input might be 10,000 Ohms.

 

[Kijanki]

Inductance is more important when load impedance is low (speaker cable), while capacitance plays bigger role when load impedance is higher (interconnects). In either case twisting wires (reduces inductance, increases capacitance) is beneficial since it exposes both wires evenly to external electric or magnetic fields. Electrical noise currents induced in both wires are identical causing cancelation. Very effective, as long as twist pitch is much shorter than wavelength of offending signal. At such high frequencies (GHz) shields are very effective (by means of skin effect).

 

[DVDdoug]

These are really non-issues unless you have "long" speaker wires. At audio frequencies the effects of inductive & capacitive reactance (both measured in Ohms) and resistance are insignificant compared to the audio circuit's input/output impedance.

Electric guitars and phono cartridges are high impedance and in those applications you do want a low-capacitance cable.

With speakers, the wire resistance should be low relative to speaker impedance. For example, if the wire resistance is equal to speaker impedance the voltage is cut in half and which results in 1/4 of the power (wattage). And since speaker impedance isn't constant over the frequency range, you get frequency response variations.

Resistance depends on the wire gauge and length. Here's a chart of wire gauge and resistance. If I calculated correctly it takes 300 meters of 16 AWG wire to get 4 Ohms!

 

[MacCali]

@Speedskater @Kijanki @DVDdoug I do see the point you are getting across, but to sum it up you are saying because a analog interconnect is running a higher load or much greater ohms this is what directly effects the electrical characteristics?

So if a interconnect cable with proper geometry and competent design would never be able to reach the same electrical characteristics as a speaker cable because the speaker cable only has 4-8 ohms on it. Not fully understanding ohms, but clearly that's something I should of thought about as it is part of the electrical character.

My reference to a speaker cable conductor size shows that a 12 awg is about 4.0 mm2 and even certain rca cables with like 10 mm size have only about .5 mm2 of conductor which is nearly 8 times less.

 

[Chrispy]

Because interconnects and speaker cables have different issues?

 

[Doodski]

to sum it up you are saying because a analog interconnect is running a higher load or much greater ohms this is what directly effects the electrical characteristics?

It's about the ratio of the output impedance vs the input impedance and the length of the conductor. A high output impedance and very high input impedance makes for a circuit that is more susceptible to RF, inductive reactance and capacitive reactance. By lowering the load impedance the RF and reactance effect can be decreased.

 

[kongwee]

So if a interconnect cable with proper geometry and competent design would never be able to reach the same electrical characteristics as a speaker cable because the speaker cable only has 4-8 ohms on it. Not fully understanding ohms, but clearly that's something I should of thought about as it is part of the electrical character.

speaker cable ohm is made up or resistance, inductance, capacitance. Inductance and capacitance are views as reactance. Reactance will draw more current than needed. You will hear about amplifier goes oscillation and burned due to this property. But you do not worry about this, it will be stated in some amp. These are way to protect amp into oscillation. Again you don't need to worry about such amp, they usually cost above $20k as far as I know. These amp are super widebandwith in megahertz which is expensive to produce. In cable spec, you will see capacitance value rather inductance. Lower better. For interconnect, it is not an issue as it current output is too low to burn stuffs out.

 

[MacCali]

It's about the ratio of the output impedance vs the input impedance and the length of the conductor. A high output impedance and very high input impedance makes for a circuit that is more susceptible to RF, inductive reactance and capacitive reactance. By lowering the load impedance the RF and reactance effect can be decreased.

So is there a set standard for measuring interconnect cables or are they just measured without a load on the wire such as input resistance? or output resistance?

@kongwee Yes, I kind of got this concept a little better after watching audioholics take on the matter. Not finding anything online that explains audio cable characteristics, I am certain that if you understand the simple electrical concepts you will be able to put it together but I need something that puts in the terms of audio.

I mean the only other thing I can say that may shift this entirely is would it be an issue for an interconnect cable to have equal resistance/cap/induc to a speaker cable?

 

[kongwee]

@kongwee Yes, I kind of got this concept a little better after watching audioholics take on the matter. Not finding anything online that explains audio cable characteristics, I am certain that if you understand the simple electrical concepts you will be able to put it together but I need something that puts in the terms of audio.

I mean the only other thing I can say that may shift this entirely is would it be an issue for an interconnect cable to have equal resistance/cap/induc to a speaker cable?

These impedance stuffs is complicated to understand and explain in simple term. This is AC electricity theory. Driver and crossover are part of the AC power delivery, so does the cable. High capacitance will act like a low pass filter in cable to due how it is connected. Two straight wire separated by insulation cause capacitance. Connected parallel to the network of amps, source and speaker, become inductive, thus low pass filter. For MIT Cable, they explain that cable can exist like low pass, band pass or high pass. This you have to read their white paper in their website. Generally, people treat cable as low pass but the frequency roll off is away above audible frequency. Many just ignore till it is able to damage on very niche cases like amplifier oscillation. Also, you will heard not to coil up your wire, it will cause inductance and deliver as low pass filter. I dunno what the value of this act that affect the audible frequency.

For information about shielding, twisting for two bare wire, quad core twisting. I think the website have enough explanation on it.

 

[Doodski]

So is there a set standard for measuring interconnect cables or are they just measured without a load on the wire such as input resistance? or output resistance?

I don't know what the standard measure is for interconnect cables. I suppose it depends on the cable manufacturer and what they determine to be a acceptable test to determine a rating on the cable.

 

[DonH56]

The characteristics of the cable itself are readily measured independent of the source and load using typical test equipment like four-wire ohmmeters to measure resistance and either an LCR meter or VNA (vector network analyzer) to measure L, C, and impedance.

This has all been said above, and my apologies for repeating since I have not read the whole thread (work + dealing with almost a foot of snow coming down), but some general comments:

1. Interconnects are typically coax like RG-59, RG-6 or similar cables for RCA, or twisted pairs (perhaps with shield) for XLR cables. The source is usually low-impedance (few ohms to perhaps 1k-ohm), and load high-impedance (typ 10k to 100k ohms), with bandwidth in the MHz region or above for typical consumer lengths. See e.g. https://www.audiosciencereview.com/forum/index.php?threads/interconnect-bandwidth.25441/ The resistance, capacitance, and inductance of the cable is essentially a "don't-care" at audio frequencies. These cables are designed to carry GHz RF signals.
2. Speaker cables tend to be two large-gage (low AWG number) unshielded conductors side-by-side. They usually have have much lower resistance than interconnects due to their larger size (cross-sectional area) and for audio that is essentially all that matters. The large size and parallel construction tends to provide comparable to lower L (inductance) and C (capacitance) but much lower resistance. Lower R is important because source and load impedances tend to be very low (<<1 ohm amp source, usually few ohms to few tens of ohms speaker load), and the low impedances make L and C practically irrelevant since bandwidth is so very low (~20 kHz). See e.g. https://www.audiosciencereview.com/...amping-factor-and-speakers.23968/#post-807327 to see how amplifier + speaker cable impedance can impact the frequency response. It is usually dominated by the amplifier's output impedance and speaker load so reasonable speaker cables will work almost all the time.

HTH - Don

 

[MacCali]

These impedance stuffs is complicated to understand and explain in simple term. This is AC electricity theory. Driver and crossover are part of the AC power delivery, so does the cable. High capacitance will act like a low pass filter in cable to due how it is connected. Two straight wire separated by insulation cause capacitance. Connected parallel to the network of amps, source and speaker, become inductive, thus low pass filter. For MIT Cable, they explain that cable can exist like low pass, band pass or high pass. This you have to read their white paper in their website. Generally, people treat cable as low pass but the frequency roll off is away above audible frequency. Many just ignore till it is able to damage on very niche cases like amplifier oscillation. Also, you will heard not to coil up your wire, it will cause inductance and deliver as low pass filter. I dunno what the value of this act that affect the audible frequency.

For information about shielding, twisting for two bare wire, quad core twisting. I think the website have enough explanation on it.

Oh yes, I do see that the cables with complex geometry are doing fairly well. Reactance[Cap/Induct] is the factors that play a lot of this low pass high pass filters.

However, to my knowledge I would have to say an RCA or XLR cable for non professional use will not have this issue. Most cables are suffering with greater lengths. At typical 3 ft RCA or XLR should we any competent build suffer from this issue.

My curiosity just stems from why the difference, and so far we see input and output impedance. The cables I am looking at are not cheap almost 50x more expensive than your average rca cable, and the measurements seem to be riding in the 14 gauge zip cord level which also probably costs somewhere in the 50x lower price.

So just using simple logic, why would you buy an RCA cable. Buy a speaker cable with a drain line and make it RCA. If it doesn't come with it you can simply make your own and save loads of money. However as we see the kicker right now is we do not know what difference in ohms is doing. We can say for certain less watts are going through with higher ohm, like with headphones running 300 ohms, but I am not sure how wattage plays on interconnects which runs on volts I am sure the volts can probably turned into watts and vice-versa.

Was hoping someone that is with an electrical background could chime in with definite results or answers and think we may have it with @DonH56

 

[SIY]

Oh yes, I do see that the cables with complex geometry are doing fairly well. Reactance[Cap/Induct] is the factors that play a lot of this low pass high pass filters.

However, to my knowledge I would have to say an RCA or XLR cable for non professional use will not have this issue. Most cables are suffering with greater lengths. At typical 3 ft RCA or XLR should we any competent build suffer from this issue.

My curiosity just stems from why the difference, and so far we see input and output impedance. The cables I am looking at are not cheap almost 50x more expensive than your average rca cable, and the measurements seem to be riding in the 14 gauge zip cord level which also probably costs somewhere in the 50x lower price.

So just using simple logic, why would you buy an RCA cable. Buy a speaker cable with a drain line and make it RCA. If it doesn't come with it you can simply make your own and save loads of money. However as we see the kicker right now is we do not know what difference in ohms is doing. We can say for certain less watts are going through with higher ohm, like with headphones running 300 ohms, but I am not sure how wattage plays on interconnects which runs on volts I am sure the volts can probably turned into watts and vice-versa.

Was hoping someone that is with an electrical background could chime in with definite results or answers and think we may have it with @DonH56

Listen to Don.

Executive Summary:

1. Interconnects are HIGHLY noncritical electrically. Get something which is mechanically sound and has decent shielding. That will be very inexpensive.

2. For 99.99% of consumer use, the only thing that matters for speaker cable is resistance. Period. Twelve gauge twin lead from Home Depot or wherever will work as well or better than any fancy "audiophile" wire.

3. There is more bullshit surrounding wire than just about everything else in audio put together. It is all bullshit. As soon as you hear someone talking about complex geometries or exotic materials or shielded speaker cord or dielectric biasing or Teflon-silver, clamp your hand over your wallet and back out the door. Yes, they are lying. Yes, the "reviewers" are lying. Yes, your audiophile friends have been suckered. And they will doubtless push you to be as well.

4. As a corollary, someone creative can always come up with some weird edge case where something fancier is needed. You are not that edge case.

 

[MacCali]

The characteristics of the cable itself are readily measured independent of the source and load using typical test equipment like four-wire ohmmeters to measure resistance and either an LCR meter or VNA (vector network analyzer) to measure L, C, and impedance.

This has all been said above, and my apologies for repeating since I have not read the whole thread (work + dealing with almost a foot of snow coming down), but some general comments:

1. Interconnects are typically coax like RG-59, RG-6 or similar cables for RCA, or twisted pairs (perhaps with shield) for XLR cables. The source is usually low-impedance (few ohms to perhaps 1k-ohm), and load high-impedance (typ 10k to 100k ohms), with bandwidth in the MHz region or above for typical consumer lengths. See e.g. https://www.audiosciencereview.com/forum/index.php?threads/interconnect-bandwidth.25441/ The resistance, capacitance, and inductance of the cable is essentially a "don't-care" at audio frequencies. These cables are designed to carry GHz RF signals.
2. Speaker cables tend to be two large-gage (low AWG number) unshielded conductors side-by-side. They usually have have much lower resistance than interconnects due to their larger size (cross-sectional area) and for audio that is essentially all that matters. The large size and parallel construction tends to provide comparable to lower L (inductance) and C (capacitance) but much lower resistance. Lower R is important because source and load impedances tend to be very low (<<1 ohm amp source, usually few ohms to few tens of ohms speaker load), and the low impedances make L and C practically irrelevant since bandwidth is so very low (~20 kHz). See e.g. https://www.audiosciencereview.com/...amping-factor-and-speakers.23968/#post-807327 to see how amplifier + speaker cable impedance can impact the frequency response. It is usually dominated by the amplifier's output impedance and speaker load so reasonable speaker cables will work almost all the time.

HTH - Don

Yes, I am fully aware that to avoid issues with frequency response you want the outputting device to be ~10x less than input device, which is why most amps are 10,000 and as you stated an output device would be 1000 at the higher points.

"These cables are designed to carry GHz RF signals" so is that what you are saying is coming out of the dac? the dac has no limit to frequency output? I think from amirs video's, which I did not really comprehend is higher 192khz is actually playing out to 192khz, I did not actually correspond those sample rate to what the dac is putting out. Didn't tie that together until it was pointed out. I do not want to talk about this subject, but at 192 khz you are able to hear about half of that. 44.1khz you get about 22k out which covers the entire band. Lets not talk about this though, this is just a light bulb moment.

Yes, logically I did tie the conductor size to different electrical characteristics. With the tests on audioholics regarding speaker cables that's the pattern I saw. Even with two cables of equal gauge the proper geometry cable was having far superior performance in some aspects, but reactance is acting up. I mean on longer speaker cables this maybe something to consider, not a huge deal on interconnects especially for at home use.

I think probably to sum up everything, is that even the most expensive interconnect cable with greatest measurements is not going to provide better sound but rather not create any limitations or degradation to the frequency response.

On a sidenote

I am very new to audio, just started in september of 2020, so I am just over a year and half in. Sometimes I get these random thoughts that I would like to learn about or better understand. Even after watching and investigating so much, and now even further justified by Amir and Audioholics. Just a very general knowledge I have in physics has told me that I am not going to invest a foolish amount of money into cables, it doesn't really make sense at all.

I just use some Monolith RCA cables and some mogami XLR's which measurement wise do have some good noise rejection with testing to prove it. Honestly see no issues there and compared to my old cables I do see that it[RCAs] does "sound" better which maybe just placebo. The only other thing that makes me wonder, and I do not wish to discuss it as we have no way of proving it, is if different metals have any sound characteristics as most people say. Measurement wise I do not think there will be a way to tell, and I am not sure if different metals will have different electrical characteristics which is what people are hearing. Even then that one is strange to me because you have a cable lets say is all silver, and then you put it on connectors which are silver plated and brass under or copper, and you would have to assume that's almost bottlenecking any performance you would actually gain.

The only final factor which comes into play crystal structure and the crap they have in marketing. I honestly cant even truly understand that and my current research which started this topic shows that a cable with 99.99999 cable is actually measuring worse than it's 99.99 counter-part and costs double. So not seeing any real influence there. Also considered conductor size on this matter, and the better measuring cable does have twice as much conductor, however the rest of the performance is almost 3 times as bad so the purity of the conductor plays no role.

 

[MacCali]

Listen to Don.

Executive Summary:

1. Interconnects are HIGHLY noncritical electrically. Get something which is mechanically sound and has decent shielding. That will be very inexpensive.

2. For 99.99% of consumer use, the only thing that matters for speaker cable is resistance. Period. Twelve gauge twin lead from Home Depot or wherever will work as well or better than any fancy "audiophile" wire.

3. There is more bullshit surrounding wire than just about everything else in audio put together. It is all bullshit. As soon as you hear someone talking about complex geometries or exotic materials or shielded speaker cord or dielectric biasing or Teflon-silver, clamp your hand over your wallet and back out the door. Yes, they are lying. Yes, the "reviewers" are lying. Yes, your audiophile friends have been suckered. And they will doubtless push you to be as well.

4. As a corollary, someone creative can always come up with some weird edge case where something fancier is needed. You are not that edge case.

Yes read my comment that follows yours, I totally agree to all of that. Even provide a tiny bit more insight to what I learned about this continuous cast metals and how amazing they are lol. The cable may have better oxidative properties, but that's about it and in such a sealed environment with the jacket insulation etc it's going to be even harder for it to experience any of that.

 

[kongwee]

Oh yes, I do see that the cables with complex geometry are doing fairly well. Reactance[Cap/Induct] is the factors that play a lot of this low pass high pass filters.

However, to my knowledge I would have to say an RCA or XLR cable for non professional use will not have this issue. Most cables are suffering with greater lengths. At typical 3 ft RCA or XLR should we any competent build suffer from this issue.

My curiosity just stems from why the difference, and so far we see input and output impedance. The cables I am looking at are not cheap almost 50x more expensive than your average rca cable, and the measurements seem to be riding in the 14 gauge zip cord level which also probably costs somewhere in the 50x lower price.

So just using simple logic, why would you buy an RCA cable. Buy a speaker cable with a drain line and make it RCA. If it doesn't come with it you can simply make your own and save loads of money. However as we see the kicker right now is we do not know what difference in ohms is doing. We can say for certain less watts are going through with higher ohm, like with headphones running 300 ohms, but I am not sure how wattage plays on interconnects which runs on volts I am sure the volts can probably turned into watts and vice-versa.

Was hoping someone that is with an electrical background could chime in with definite results or answers and think we may have it with @DonH56

For me, I just buy Belden 8333x series, two core, three core. I done. 85% shielding, very low capacitance, 460V 16 amp. Can make into RCA, XLR, power and speaker cable. Highly over spec cable. Just need to diy that cable.

 

[SIY]

For me, I just buy Belden 8333x series, two core, three core. I done. 85% shielding, very low capacitance, 460V 16 amp. Can make into RCA, XLR, power and speaker cable. Highly over spec cable. Just need to diy that cable.

@MacCali this is poor advice and an example of the sort of thing you should ignore. Plain coaxial construction for normal interconnects is optimal. Twin lead for speaker cables, ditto. Cheap, easy, effective.

edit: I should add 5.

5. There's no reason to build your own wires unless you've got an oddball setup or (like me) you're using your equipment for test and measurement as well as music reproduction and need different connector pairings for different devices under test.

 

[Doodski]

The only other thing that makes me wonder, and I do not wish to discuss it as we have no way of proving it, is if different metals have any sound characteristics as most people say. Measurement wise I do not think there will be a way to tell, and I am not sure if different metals will have different electrical characteristics which is what people are hearing. Even then that one is strange to me because you have a cable lets say is all silver, and then you put it on connectors which are silver plated and brass under or copper, and you would have to assume that's almost bottlenecking any performance you would actually gain.

The variations in metals that are used will create higher or lower resistance in the cable. When dealing with speaker cable the load resistance/speaker is say 4 or 8 ohms and the source impedance/amplifier is down in the fractions of a ohm or better. So the voltage drop across the speaker wire will not change things very much unless it is high enough to cause a decrease in sound output from the speaker.

A conductor has a certain range of electrons in the outer valence ring and that makes it a conductor or a semi-conductor. Normally, a conductor has three or less valence electrons, an insulator has five or more valence electrons, and semiconductors usually have four valence electrons. All the elements of which matter is made may be placed into one of three categories: conductors, insulators, and semiconductors.

(Simplified) So by changing the metals used in the speaker wire the resistance will change due to the quantity of valence ring electrons in the specific metal. The frequency response does not change due to the metal type used. The speaker wire is represented in a model circuit as a resister. A model resister does not affect frequency; it only affects the current through it and the voltage drop across it.

So the long and short of speaker cable is use the best conductor for the job although don't buy snake oil. 12 gauge is the best value for the money and does the job very well.