GA, Impedance, and Sound for Speaker Cables [Archive] - Audio & Video Forums

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nightflier
05-29-2009, 11:39 AM
I just came across this article on Audioholics:

http://www.audioholics.com/education/cables/speaker-cable-gauge

In a nutshell, the author claims that proper length depends on the load (impedance) of the speaker, and his findings are:

18 AWG
Distance for 8ohm load: 10 ft
Distance for 4ohm load: 5 ft

16 AWG
Distance for 8ohm load: 20 ft
Distance for 4ohm load: 10 ft

14 AWG
Distance for 8ohm load: 35 ft
Distance for 4ohm load: 18 ft

12 AWG
Distance for 8ohm load: 60 ft
Distance for 4ohm load: 30 ft

10 AWG
Distance for 8ohm load: 100 ft
Distance for 4ohm load: 50 ft

Now this flies in the face of some very reputable cable manufactures like Kimber and Mapleshade who actually sell much higher gauge cables in these lengths. So my question is what is the actual effect on the sound? For example, what will I hear if I use 18GA wire (Mapleshade Golden Parallels) to drive a 4 ohm speaker (my Vienna Weberns) located some 20' from my amp? And what would happen if I replaced my speakers with 1.6QR Maggies, for example? Anyone have any experience with these scenarios?

Feanor
05-29-2009, 12:06 PM
I just came across this article on Audioholics:

http://www.audioholics.com/education/cables/speaker-cable-gauge

In a nutshell, the author claims that proper length depends on the load (impedance) of the speaker, and his findings are:

18 AWG
Distance for 8ohm load: 10 ft
Distance for 4ohm load: 5 ft
....
Now this flies in the face of some very reputable cable manufactures like Kimber and Mapleshade who actually sell much higher gauge cables in these lengths. So my question is what is the actual effect on the sound? For example, what will I hear if I use 18GA wire (Mapleshade Golden Parallels) to drive a 4 ohm speaker (my Vienna Weberns) located some 20' from my amp? And what would happen if I replaced my speakers with 1.6QR Maggies, for example? Anyone have any experience with these scenarios?

Audioholics, as I recently noted myself, has an "objectivist" bias. According to the above info the 18 GA Mapleshades shouldn't work very well at 20' with either the Viennas or the Maggies (also 4 ohms).

But true audiophiles know better than to accept the findings of mere science and engineering. Its quite possible that the Mapleshades defy the laws of physics in some ingenius way.

nightflier
05-29-2009, 12:26 PM
Audioholics, as I recently noted myself, has an "objectivist" bias. According to the above info the 18 GA Mapleshades shouldn't work very well at 20' with either the Viennas or the Maggies (also 4 ohms).

But true audiophiles know better than to accept the findings of mere science and engineering. Its quite possible that the Mapleshades defy the laws of physics in some ingenius way.

I got an email from their top guru just an hour ago and he said exactly the same thing. They have a 30-day return guarantee, so I think I'm going to go for it anyhow.

Smokey
05-29-2009, 10:36 PM
So my question is what is the actual effect on the sound? For example, what will I hear if I use 18GA wire (Mapleshade Golden Parallels) to drive a 4 ohm speaker (my Vienna Weberns) located some 20' from my amp?


Well according to the formula from AH (Loss= Log*20 (Rload / (Rload + Rcable)), you will have signal loss in term of cable resistance. And since cable resistance effect all the frequency, the worst case scenario will be volume drop from your system.


Now this flies in the face of some very reputable cable manufactures like Kimber and Mapleshade who actually sell much higher gauge cables in these lengths.

The formula is plain as the day, so there is no way these guys can get around the law of physics.

Kevio
05-30-2009, 08:10 AM
You've got three components involved here - speakers, cables and amplifier. Each has an impedance. The wire gauge recommendations referenced above are contrived to make cable impedance small compared to speaker impedance with the objective of tightly coupling the amplifier and speaker and preventing the cabling from coloring the sound.

I believe the objective of some of these high-end cable manufacturers is to color the sound in a pleasing way. A cable with significant impedance could do that.

LeRoy
06-01-2009, 07:07 PM
It's always so darn hard to choose speaker wire and interconnects without first having heard the effect on the entire system. Through an accidental purchase at Radio Shack, I picked up a spool of 30 gauge Wrapping wire and used it as speaker wire going bare wire to the amp and to the speakers. In my quest for improving the system sound by speaker wire I found the R.S. Wrapping wire to be superior to that of vampire wire, DNM Reson, and Mapleshade's entry level wires and given the difference in the prices of boutique speaker wire...I felt pretty stupid for having sought out boutique speaker cables to begin with.

No, I don't work for R.S. or own stock in R.S. and every time I tell the R.S people what I use it for they just don't know what to make of it....nevertheless, for the money, $3.99 for a 50ft spool, its the best speaker wire for the least amount of money I've ever found.

However, my recent purchase of Chord Carnival Silver Screen 8ft speaker cables terminated, $115.00 is the most musically satisfying speaker cable I have ever bought or used. The C.C.S.S has been the difference maker in transforming my Nola Mini's wired to my Rega Brio 3 into an open, very organic sound while adding a bit of "air" to the musical presentation. I am now officially hooked on Chord products.

markw
06-01-2009, 11:30 PM
I'm pretty sure the numbers and lengths you list from the Audioholics article are maximum recommended lengths before insertion loss becomes an issue. Shorter lengths and/or lower gauges should be fine.

bfalls
06-02-2009, 05:10 AM
Speaker wire has more than a resistance parameter, it also has capacitance and inductance contributing to the speaker's impedance. These parameters are affected by the conductors geometry and materials as well as length. Flat wires, such as Nordost Flatlines, tend to have more capacitance. Each cable will have it's own sound depending on these three components and their effect working with the speaker's xover.

Stating a specific length according to resistance and the speaker's impedance only, sounds short-sided and too general. Sounds more like a "rule-of-thumb". Most "technical" audiophiles (those who understand the electrical and physics of the system) don't operate in this region. They tend to know the parameters of their systems exactly, so they can evaluate how minor changes deviate from their reference. The chart may be a good general tool for determining GA and length of the cable, but your ears and trial and error, will still make the final judgment.

nightflier
06-03-2009, 04:24 PM
LeRoy, how far are you going with the RS wire and the C.C.S.S.? And what equipment are you using it with?

LeRoy
06-06-2009, 02:17 PM
Hi nightflier, with the R.S. wire I was using 8 ft lengths, bi-wired to the Usher's, going bare wire to amp and speakers for the 2 channel set up.

With the CCSS I am using 8 ft lengths, terminated at both ends also for the 2 channel set up. I am currently using the CCSS for Nola Mini's to the Brio 3 integrated---- and the CCSS is/was the difference maker in my setup which also includes NAD 545 BEE CD player.

I am currently still using the R.S. wire for my H.T. setup which consists of Mirage Nanosats to an Arcam AVR 200 receiver. The lengths of RS wire for front and center speakers are 6 feet and the lengths for each of the 2 rears speakers is approx 42ft. The Nanosats cannot be bi-wired and I use the wire bare at both ends.

The RS wire is so inexpensive and so good that this is the only wire I will ever use for HT.

02audionoob
06-06-2009, 03:39 PM
Sounds like a very loose definition of good. A 42-foot 30-gauge conductor is good?

markw
06-06-2009, 04:22 PM
Sounds like a very loose definition of good. A 42-foot 30-gauge conductor is good?Apparantly so. I guess it IS all subjective. Screw physics.

LeRoy
06-06-2009, 07:11 PM
Good points 02audionoob and markw...er rather I should say points well taken. I should clarify that I mean '"good" being relative to what I was using before and the R.S.Wrapping Wire is audibly more satisfying to my ears than vampire wire, DNM reson, and the Mapleshade wires I was using.

No doubt the laws of physics applies to all speaker wires. However, regardless of how speaker wire may measure by way of machine tests the wire integrates well with all the other equipment or it doesn't. In my experience with the R.S wire I simply find it to be a more musical conductor than the vampire, DNM, and Mapleshade. It just works.

My inspiration for going to R.S. in the first place was due a review I read on enjoythemusic.com. The review was on the Moth Cicada speakers and the reviewer went on to state that R.S. had a great wire called Magnet Wire 30 gauge. So, I went to R.S. to buy some Magnet Wire and picked up the Wrapping Wire instead ( I thought they were the same thing but they are not). At any rate, while the RS wrapping wire has been dethroned (in my system) by the physics of the CCSS it still is nevertheless a good speaker wire.

nightflier
06-09-2009, 02:38 PM
LeRoy, I searched the RS website and can't find the wire you're talking about. Can you provide a link?

Also, does this wire have any major issues with interference from nearby wires (as in a conduit), materials, or equipment?

LeRoy
06-13-2009, 05:32 AM
Nightflier, sorry for the delayed reply...The RS wire is named, Insulated Wrapping Wire, and the product number # 278-502 is for the white insulated coat on the wire. RS also makes Red coated wire prod# 278-501, and Blue coated wire prod# 278-503. There is no difference in price or performance so it's simply a matter of which colors you want to work with. I have used all 3 colors to be sure...lol

You would also need a Wire Wrap Tool, prod# 276-1570, which I paid $6.99 for. If you decide to use this wire I have a word of advise for you....if you try to unravel the wire from the spool too fast..it will probably birdnest and kink up on you like when fishing line comes off the reel....so try to unspool only what you need as you go along. Oh, and the wire wrap tool has a cap on top that you remove and inside is where you will find the wire stripper. I tried to use a conventional wire stripper before getting the wrap tool but no way that would ever work.

At any rate, here is the website: http://www.radioshack.com/product/index.jsp?product

I will check back in for feedback from you in a week. Have a good one.

LeRoy
06-13-2009, 05:40 AM
Nightflier, I have experienced no issues with the wrapping wire other than the kinking and birdnesting I mentioned before. The wire is very thin so it's easy to "snap" if you run over it with the vacuum cleaner or walk "through" it when it's connected to your system. I have never experienced interference from this wire ever but I have tile floors and not carpeted floors. I have run the wires over each other and also over and around powers strips, audio cables, and power cords without any interference heard.

hermanv
06-13-2009, 03:19 PM
There are some rules of thumb concerning cables with respect to impedance that fit well within physics.

1. For interconnect cables, capacitance tends to dominate due largely to the output impedance of the previous piece of equipment. For example a pre-amp with a 200 Ohm output impedance will result in a 1/10 db of loss at 20KHz for a capacitance of about 400pF/ft at 8 feet.

2. Conversely speaker cable loss is dominated by inductance due to the low load impedance at 20 KHz. For example the same 1/10 dB of loss happens for an 8 foot cable with a 4 Ohm load and an inductance of about 5uH.

3. Speaker cable is also very sensitive to resistive loss, less loss is usually better.

In summary, interconnect cable DCR is less important capacitance is important very insensitive to inductance. For speaker cable DCR is important as is inductance, it is very insensitive to capacitance.

All of the above implies that intentional tunning is not the goal.

markw
06-14-2009, 08:15 AM
In summary, interconnect cable DCR is less important capacitance is important very insensitive to inductance. For speaker cable DCR is important as is inductance, it is very insensitive to capacitance.DCR = DC Resistance?

hermanv
06-14-2009, 11:21 AM
DCR = DC Resistance?
Yep.

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