Self explanatory. 18 gauge is the limit where there is no skin effect rolling the highs. Thinner cables have less reactivity (inductance and capacitance) but offer more resistivity. Resistivity is linear and has no effect to sound quality other than lowering sensitivity. I see no reason to buy thicker cables.
If you use Ohms Law, the thicker the copper in the cable, the lower the resistance which means more power goes to the load as less is lost in the cabling.
If you are using an 8R speaker say 12feet away from the amplifier and use 18AWG cable, that will be fine below around 30Watts of power. If you measure the resistance of the cable and using the loudspeaker resistance as a reference, Boyles Law will show you how much loss there is in your cables.
If you are using an 8R speaker say 12feet away from the amplifier and use 18AWG cable, that will be fine below around 30Watts of power. If you measure the resistance of the cable and using the loudspeaker resistance as a reference, Boyles Law will show you how much loss there is in your cables.
If the speaker used has impedance that varies with frequency, as most do, then the voltage at the speaker terminals
will tend to resemble the impedance curve in shape. The greater the wire resistance [or amplifier output impedance],
the more the aberration. Here's an example, see fig. 1. Audio Research VSi60 integrated amplifier Measurements | Stereophile.com
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What does this aberration do in regards to sound quality? I read that resistivity has no effect to sound quality other than lowering the sensibility.
Tube amps work in a different way than the solid state ones, impedance peaks can cause damage to tube amps while it is harmless to solid state ones, maybe this aberration happens only with tube amps.
That's not true, it depends on the particular speaker and amplifier.
Some solid state amps do have a moderate output impedance as well,
but most are low enough in output impedance that the effect is unimportant.
In large scale public address systems, the long cables used do cause serious
aberrations in the acoustic output unless carefully dealt with.
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Skin effect is in V high frequencies NOT audio ones. So that's just silly.
10 gauge is a fairly common suggested wire size for Speaker power (unless some 70 V non residential install)
Resistance is effectively the Only significant spec in a Power (speaker) wire.. Clever to avoid it... unless Seriously skilled at using that resistance to correct some other system problem
But you can do what ever you want.
Just don't be expecting ideal results
10 gauge is a fairly common suggested wire size for Speaker power (unless some 70 V non residential install)
Resistance is effectively the Only significant spec in a Power (speaker) wire.. Clever to avoid it... unless Seriously skilled at using that resistance to correct some other system problem
But you can do what ever you want.
Just don't be expecting ideal results
The skin depth is about 0.018" for a solid wire at 20kHz, so a 22 gauge is the largest diameter
of wire that would be 100% used. For 10 gauge, only 68% would be used at 20kHz.
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IMO, skin depth is somewhat of a red herring. There aren't usually impedance dips in the upper frequency ranges, if anything impedance rises, so less than 100% usage is OK. At the lower frequencies where you find all sorts of impedance changes, skin effect is negligible, so larger wire can have benefits. IMO again, the greater the impedance change, the more beneficial is low resistance. Remember too that skin depth isn't a sudden boundary and thinking about it in terms of great precision is a bit misleading.
Skin effect is in V high frequencies NOT audio ones. So that's just silly.
10 gauge is a fairly common suggested wire size for Speaker power (unless some 70 V non residential install)
Resistance is effectively the Only significant spec in a Power (speaker) wire.. Clever to avoid it... unless Seriously skilled at using that resistance to correct some other system problem
But you can do what ever you want.
Just don't be expecting ideal results
Capacitance and inductance are important , because the first can put a strain in the amplifier and roll the lows, while the second rolls the highs.
I only want to say that in the last 40 years i have tried a lot of speaker wires, as big as 10g, but have ended up now using a single pair of wires from a CAT5 cable. Decent copper, 24g solid. Cheap but very good. Granted my runs are shortish (typically <2m) and i mostly used single driver speakers.
dave
dave
As the capacitance will be in parallel, and the inductance in series, they will both have the effect of rolling off highs.
Damping factor. A typical loudspeaker will have a minimum impedance half that of the rated impedance. Damping factor begins to creep up at 10% of that.
So .4 ohms would be a reasonable goal. Limits you to less than 10M of cable. (Two wires per cable.)
But to really mess things up, small short cables often have higher resistance than book values and you have to add in the connection resistance. Add .01 ohm per good clean posts or .04 ohms minimum per cable.
So .4 ohms would be a reasonable goal. Limits you to less than 10M of cable. (Two wires per cable.)
But to really mess things up, small short cables often have higher resistance than book values and you have to add in the connection resistance. Add .01 ohm per good clean posts or .04 ohms minimum per cable.
Or is the loudspeaker designed improperly to match a specific amplifier set up?
It is a system. Does the chicken or the egg come 1st?
But given the imperfect nature of the speaker it plays an overly large role in the voice of a system, so there is an argument that says you should start by choosing the speaker that best suits your room, taste, budget and then looking for an appropriate amplifier. Complicated by the fact that unless you are just taking a shot in the dark, you have to audition the speakers with an amplifier hooked up.
dave
But given the imperfect nature of the speaker it plays an overly large role in the voice of a system, so there is an argument that says you should start by choosing the speaker that best suits your room, taste, budget and then looking for an appropriate amplifier. Complicated by the fact that unless you are just taking a shot in the dark, you have to audition the speakers with an amplifier hooked up.
dave
At risk of walking into another hornets nest , i' ve never really considered that differences in cable length make much of a change in sound , but , i recently did a bit of system 'housekeeping' and i took the opportunity to reduce the length of the cables on each channel from 5 metres down to 2.75 , as repositioning my equipment meant i didn't need such long lengths.
When i got the system up and running again everything sounded a touch cleaner and a bit more focused.
Nothing new , as part of my yearly ' service ' i give the plugs and sockets a good clean and remove the banana plugs , cut back the ends to expose fresh wire and re-fit the plugs, which normally results in a perceived increase in sound quality .
I've always assumed this was mostly due to my mental state after doing the maintenance , kind of knowing the gear was clean , tidy and ' fresh ' therefore working at it's best.
This time though the improvements seemed a lot more noticable than normal so maybe i did accidentally hit the ' sweet spot ' for cable length in my system ?
Anyone thats seen some of my posts elsewhere will know that i 'm generally a sceptic when it comes to cables , especially when things like skin effect gets mentioned, but i do remain open minded.... i even purchased an Audioquest RCA cable recently, i was drunk though
When i got the system up and running again everything sounded a touch cleaner and a bit more focused.
Nothing new , as part of my yearly ' service ' i give the plugs and sockets a good clean and remove the banana plugs , cut back the ends to expose fresh wire and re-fit the plugs, which normally results in a perceived increase in sound quality .
I've always assumed this was mostly due to my mental state after doing the maintenance , kind of knowing the gear was clean , tidy and ' fresh ' therefore working at it's best.
This time though the improvements seemed a lot more noticable than normal so maybe i did accidentally hit the ' sweet spot ' for cable length in my system ?
Anyone thats seen some of my posts elsewhere will know that i 'm generally a sceptic when it comes to cables , especially when things like skin effect gets mentioned, but i do remain open minded.... i even purchased an Audioquest RCA cable recently, i was drunk though
Transient rise times can be described as equivalent to high frequencies, beyond 20 KHz. Put another way, with limited high frequency response, square waves show limited rise time.
The late Allen Wright was a proponent of using wire and cable as small as practical, but no smaller.
He also was a proponent of wide frequency response in electronics, with an upper limit "at least one, and preferably more than one, decade" higher than the highest frequency the unit was intended to reproduce in a steady state sine wave.
So, one would assume he would seek a speaker cable capable of 200 KHz without losses.
And then there was an article, many years ago, in Glass Audio or Speaker Builder magazine where they measured a number of commercial loudspeaker cable (all the usual suspects you would expect in a circa late 90's marketplace), plus 18Ga, 14Ga and 12Ga "zip cord". I don't believe the article is available online; I have it in hard copy somewhere (but I don't know where right now).
They found, amongst other things, that there seemed to be no advantage to using a speaker cable larger than 12Ga, but that in that size they did measure somewhat better than smaller variants. Another finding was they all tested differently; no two were alike (inductance, capacitance, square wave response).
Damping Factor is measured and specified by manufacturers at 1 KHz; we are most interested in the DF at below 100 Hz, so the specification isn't particularly valuable (typically it falls as the frequency falls).
However, if you did measure the output resistance of an amplifier at, say, 50 Hz, and included the mandatory resistance of the loudspeaker cable (both ways, so a 5' cable we would use the value for 10' of a single conductor) and any resistance of the crossover and loudspeaker all added together, you would then have a useful DF calculation. The short answer is it's a lot lower than many assume, even with Solid State devices.
Personally I use a 15Ga speaker wire (2x 2x 18 Ga) 1.5 metres long per side, with a 40 watt tube amp on the 4 ohm tap (speaker impedance 6 ohms dipping to 3.2 ohms). Is it the ideal cable for my setup? I really don't know. All I looked for is minimum inductance, let capacitance fall where it may (within reason) and keep the length as short as practical.
I haven't experimented (much) with other speaker cables, but the few I did try differed somewhat in subtle ways. I have no idea what that means with regard to advising someone what to choose. I found a greater difference by trying the 4 and 8 ohm taps. I'm firmly in the "try it and see" camp when it comes to what others should do.
Another thing that is often not mentioned in reviews (amateur or professional) of speaker cables, or cable in general, is where the reviewer lives. This is, in my opinion, a critical criteria. Whether it's sea air or environmental pollutants or the ideal dry air of the plains in North America, corrosion can play a huge role in the amplifier-speaker interface. I suspect (but do not know) that someone in, say, Los Angeles would have different needs than someone in, say, New Mexico, where a pure copper conductor might fare better. In LA maybe you want mil-spec silver over copper? In any case, I think it's relevant.
The late Allen Wright was a proponent of using wire and cable as small as practical, but no smaller.
He also was a proponent of wide frequency response in electronics, with an upper limit "at least one, and preferably more than one, decade" higher than the highest frequency the unit was intended to reproduce in a steady state sine wave.
So, one would assume he would seek a speaker cable capable of 200 KHz without losses.
And then there was an article, many years ago, in Glass Audio or Speaker Builder magazine where they measured a number of commercial loudspeaker cable (all the usual suspects you would expect in a circa late 90's marketplace), plus 18Ga, 14Ga and 12Ga "zip cord". I don't believe the article is available online; I have it in hard copy somewhere (but I don't know where right now).
They found, amongst other things, that there seemed to be no advantage to using a speaker cable larger than 12Ga, but that in that size they did measure somewhat better than smaller variants. Another finding was they all tested differently; no two were alike (inductance, capacitance, square wave response).
Damping Factor is measured and specified by manufacturers at 1 KHz; we are most interested in the DF at below 100 Hz, so the specification isn't particularly valuable (typically it falls as the frequency falls).
However, if you did measure the output resistance of an amplifier at, say, 50 Hz, and included the mandatory resistance of the loudspeaker cable (both ways, so a 5' cable we would use the value for 10' of a single conductor) and any resistance of the crossover and loudspeaker all added together, you would then have a useful DF calculation. The short answer is it's a lot lower than many assume, even with Solid State devices.
Personally I use a 15Ga speaker wire (2x 2x 18 Ga) 1.5 metres long per side, with a 40 watt tube amp on the 4 ohm tap (speaker impedance 6 ohms dipping to 3.2 ohms). Is it the ideal cable for my setup? I really don't know. All I looked for is minimum inductance, let capacitance fall where it may (within reason) and keep the length as short as practical.
I haven't experimented (much) with other speaker cables, but the few I did try differed somewhat in subtle ways. I have no idea what that means with regard to advising someone what to choose. I found a greater difference by trying the 4 and 8 ohm taps. I'm firmly in the "try it and see" camp when it comes to what others should do.
Another thing that is often not mentioned in reviews (amateur or professional) of speaker cables, or cable in general, is where the reviewer lives. This is, in my opinion, a critical criteria. Whether it's sea air or environmental pollutants or the ideal dry air of the plains in North America, corrosion can play a huge role in the amplifier-speaker interface. I suspect (but do not know) that someone in, say, Los Angeles would have different needs than someone in, say, New Mexico, where a pure copper conductor might fare better. In LA maybe you want mil-spec silver over copper? In any case, I think it's relevant.
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