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Instantaneous current demand and wire gauge?

70.197.16.26
Posted on March 5, 2016 at 13:27:56
Tweaker456
 This has been brought up as a subject of import and I can not find anything about it. Is there a science of shall we say a faster or slower current delivery from speaker demand as it relates to wire thickness. I'm thinking along the lines of something other that resistance. Tweaker

 

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RE: Instantaneous current demand and wire gauge?, posted on March 9, 2016 at 12:07:25
6bq5
Audiophile

Posts: 4393
Location: SF Bay
Joined: August 16, 2001
 Check out the link below-
otherwise-

The ability of a given wire to accommodate a given amperage is well characterized and appears as part of the IEC - and is usually given in tables where you have Volt amps on one side, wire gauge across the top and in the columns are listed the acceptable distances -
while this is not exactly what you asked - it does address the subject-

the speed of transmission is a constant- through the wire and is only affected by the connections and the supply

Typically in HiFi we are in the under 1000 V/A range - so at 120 VAC the current would be 8.334 Amps - so anything over #14 wire is good for 50 feet with negligible losses - and if you use wire better than #10 you are good to 100+ feet-
Given that many of the speaker wires commonly used are bigger - the ampacity is not really an issue - it becomes the exotic construction etc...

Happy Listening

 

RE: Instantaneous current demand and wire gauge?, posted on March 10, 2016 at 18:41:43
beautox
Manufacturer

Posts: 366
Location: New Plymouth
Joined: July 9, 2013
 For power cords: Audio gear has power supplies, typically with transformers, rectifiers and capacitors (and sometimes, regulators).

You can't just apply ohms law to work out the instantaneous current for several reasons.

1) The power supply takes current in small bites. Sometimes current is only flowing for a small percentage of the cycle. This is because of the caps and rectifiers - the rectifiers only conduct when the voltage from the transformer is higher than the voltage in the reservoir caps.

2) Usually the power supply will present a complex load, ie it's inductive. So current and voltage are not in phase. Leading to ..

3) Power factor. (look it up..)

For speaker cables : speakers are also typically complex - inductive (unless they are capacitative ;). But also a speaker has moving mass, and for example, when you get a pulse (or the music stops suddenly) the speaker keeps moving and acts as a generator, pushing current back into the amp. And if the amp has a very low output impedance, you have a generator looking into almost a short circuit, so you can get pretty high instantaneous currents.

Long and short of it - ohms law doesn't apply here either.

This is basic electronics, nothing controversial.
https://en.wikipedia.org/wiki/Electrical_characteristics_of_dynamic_loudspeakers


 

RE: Instantaneous current demand and wire gauge?, posted on March 18, 2016 at 23:22:23
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 BINGO on noting PF.


Too much is never enough

 

RE: Instantaneous current demand and wire gauge?, posted on March 10, 2016 at 08:10:13
geoffkait
 I tend to doubt all of those equations are applicable since I have heard 54 ga. Speaker Cable as I mentioned in my other post and it sounds EXTREMELY GOOD. Plus I seem to recall measuring more like 2 amps at the speaker terminals when music was playing. Could my memory be on the fade?

 

RE: Instantaneous current demand and wire gauge?, posted on November 20, 2016 at 22:37:15
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 yes, defective memory MIGHT be in play here.

2 amps @ 54ga wire? Might get away with that at a 10% duty cycle.
Too much is never enough

 

RE: Instantaneous current demand and wire gauge?, posted on November 21, 2016 at 03:49:48
geoffkait
 It was interconnects. Ooopsy daisy.

 

" It was interconnects. Ooopsy daisy.", posted on November 26, 2016 at 05:22:04
Tweaker456
 Not 54AWG speaker cable any more Sir Geoff. Ya sure?? Ooopsy daisy?

 

RE: Instantaneous current demand and wire gauge?, posted on November 22, 2016 at 23:41:55
pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008
 So much for the Memory, eh? You've got CRS.
Too much is never enough

 

RE: Instantaneous current demand and wire gauge?, posted on November 23, 2016 at 16:31:36
geoffkait
 I was close, zippy. Very close.

 

RE: Instantaneous current demand and wire gauge?, posted on March 7, 2016 at 05:21:26
geoffkait
 If there is a science behind wire gauge and current delivery it probably applies to power cords, not speaker cables. Otherwise how do you explain the super performance of the Omega Mikro speaker cables from Mapleshade the conductor of which comes in at 54 gauge? By contrast power cords for 20 amp situations have to be much larger in diameter than for 15 amp situations, no?

 

RE: Instantaneous current demand and wire gauge?, posted on March 17, 2016 at 06:00:53
Tweaker456
 54 AWG SPEAKER CABLE? No I don't think so. Sprey is not using 54 speaker cable. 2 amps through a 54 AWG wire?

 

RE: Instantaneous current demand and wire gauge?, posted on March 19, 2016 at 02:12:09
geoffkait
 The Omega Mikro cables, you know, the ones from Ron Bauman, use conductors that are the diameter of a human hair or ultra thin ribbons that are so thin you can almost see through them. You know, to minimize skin effect. (I like your reaction.)

 

RE: Instantaneous current demand and wire gauge?, posted on August 9, 2016 at 04:49:23
horn kid
Audiophile

Posts: 128
Joined: November 2, 2014
 Gage is good only in that it relates to the AC resistance, which relates to impedance. Impedance is totally different than resistance and one must be familiar with the formulae and complex mathematics to understand how this can be of benefit with wide range signal transmission with minimal phase shift. Large gage has nothing to do with "speed".

Hit the physics books, it's all there, and it certainly applies to audio signal.

 

Huh?!, posted on August 12, 2016 at 14:43:53
geoffkait
 You got me all wrong, dude. I never said any of those things. The word is gauge, incidentally.

 

dding in some trivia... Long runs wit thin gauge eally fails on bass.., posted on August 26, 2016 at 13:47:24
Smelly_Socks
 Just to mentin (somewhat of topic as this is for an IC not a speaker cable but...)
Nyway, I bought a pile of Cardas Parsec as they sounded pretty good on my system. However when I bought a 7 meter run in balanced.. The sound never di resolve. Stayed tin and not pleasing.
But a same length of Kimber Hero, (with much larger size wires) Had great bass.
IMO the Parsec had too thin a conductor over the 23 ft.
Maybe it was some other problem with the design.. But I think it was just too damn thin a wire to run 23 ft.

The treble was superb.. Just the lower depths lacking..

 

RE: dding in some trivia... Long runs wit thin gauge eally fails on bass.., posted on August 27, 2016 at 08:39:43
geoffkait
 It could be a lotta things. Who knows? There are many cables that have crappy bass, even heavy gauge ones.

 

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