A pricey power cord

[k4kyv]

I have been told and read that larger conductors have more self inductance.

I think that is one of the reason that litz wire is used? (individually insulated strands)

Must have been the same source who told you that, if sufficient wire size and sufficiently low connector resistance exist to assure negligible a.c. voltage sag, the power cord attached to an amplifier will make any difference whatever in the sound that comes out of the speaker.

Litz wire is used to reduce skin and proximity effects in a.c. conductors, primarily used in the frequency range from the upper audio frequencies up through the AM broadcast band, but also in some applications in 60~ power distribution.

http://www.litz-wire.com/applications.html

Errr, speaking of flogging mules.  Don't forget to "Fall back" and set your clocks back 1 hour this weekend....
 

this ought to get Don fired up again..........    

Something I used to look forward to every year; it's the Spring one that sucks.  Now that I am retired and no longer have to get up before the crack of dawn, I don't pay it a lot of attention.  My clock stays set on GMT anyway.

According to a news report I heard on the BBC, the UK is considering keeping their clocks advanced to GMT + 1, year-round, putting them in the same standard time zone as the rest of western Europe, but they would no longer shift their clocks backwards and forwards twice a year.

[Sam KS2AM]

Be careful when you get them though, "Each fuse is marked with an arrow, indicating the direction the current should flow. Take care to not reverse these, as it harms the sound."  
Sam

OK-FINE! ! ! ! !  Now, with the fuse fusing the incoming AC mains. If they are current flow "direction sensitive" which way do you point the arrow for AC ? ? ?

Or do you keep flipping the fuse back and forth at 60 flips per second? ?      

Well if you really care about good audio you would obviously need to flip the fuse - I think its actually 120 times per second ... otherwise just restrict your listening to only the postive going half of each 60 Hz cycle.  

[KA3EKH]

Maybe it’s all a question of measurements verses the educated ear? The thing I wonder about is back when I was in flight school one of the first things they told you was to ignore your senses and always trust the instruments. When you spend lots of money, invest hours of work or whatever to improve something don’t you just assume that it has to be better? Maybe convince yourselfer of that too? Would think it’s a fairly easy thing to do to take a system into an anechoic chamber with an audio spectrum analyzer and see if there is any difference between the plots with different power cables? Or audiophile line fuses. If a difference cannot be measured with technology how can you tell if it’s a real difference or an imagined one? Here at the university we have a recording studio. Has the floating floors and all the acoustic treatment, a Yamaha DM-2000 digital board along with huge ProTools HD system, lots of expensive microphones and the like and we have Genelec Bi- Amped near field monitors that are thought of rather highly in the industry and they came with rather cheap molded plastic 18G power cords.

[W2DU]

For Bear and Steve, when I was working with sound systems during the late 1930s I found that when using long runs of speaker cable, if the wire size was too small the self inductance of the line in series with the voice coil impedance decreased the low frequency response of the speaker significantly.

Walt

[k4kyv]

I ran into that problem just the other day, as I was working on the balanced L-network to match the transmitter coupling link to a 450-ohm load. At first, I was able to use the 900/900 pf split stator capacitor with 840 pf fixed capacitance across it, directly across the link to hit resonance and get a good match to the resistive dummy load.  But I noticed the settings of the variable capacitor kept shifting quite drastically. Then I discovered that shifting the wire leads around (#12 stranded wire) affected resonance.  The leads between link and the hastily built prototype tuner were several feet long.  So I moved the tuner to the top of the transmitter cabinet, so the wire leads were just a few inches long.  I could no longer tune the link to resonance until I added some inductance in series with it.  Next, I split the inductance into two sections using a split coil, so that half the added inductance was on each side of the link. I found the taps on the coil by trial-and-error. Once the resonant point was found, the capacitor setting was stable. In the first lash-up, the self inductance of the wire leads was serving as the L-network coil, which was replaced by a real coil in the final circuit.

For Bear and Steve, when I was working with sound systems during the late 1930s I found that when using long runs of speaker cable, if the wire size was too small the self inductance of the line in series with the voice coil impedance decreased the low frequency response of the speaker significantly.

Walt

Walt, was that a typo? It would seem to me that if the wire size is too small, the additional self inductance of the smaller wire in series with the voice coil would decrease the high frequency response significantly.

[The Slab Bacon]

that may well have been an I2R issue. The increased resistance of the long cable runs may have caused a sag under load as the bass notes require a lot more current to move the speaker cones that heavily.

Just my $.02 worth..............

[WBear2GCR]

For Bear and Steve, when I was working with sound systems during the late 1930s I found that when using long runs of speaker cable, if the wire size was too small the self inductance of the line in series with the voice coil impedance decreased the low frequency response of the speaker significantly.

Walt

Walt, the series inductance would only want to roll off the highs, not the lows. Otoh, the series resistance of the long run of wire would tend to reduce the control that the amp because the output Z of the amp would look higher. But that tends to make the lows more "fat" or "wooly" or accentuate a resonance peak... wait a sec, the last two guys said that too... hehe.

                         _-_-bear

[w3jn]

Fuses are non-linear devices. Good to avoid in audio if possible.

Huh?  A piece of wire in a glass tube is non-linear?

PS. for sure almost anyone on here can make their own line cord using "good" parts - but figure out the actual cost of materials, premium materials including the aesthetic finishing stuff, add it up report back and then multiply that by 5, that is your retail price. It won't be as low as you think. Thus, a few hundred today is reasonable.

Much more unreasonable than your run-of-the-mill IEC power cable, available at any hamfest for a quarter or so...

[W1RKW]

damping factor

[WBear2GCR]

Fuses are non-linear devices. Good to avoid in audio if possible.

Huh?  A piece of wire in a glass tube is non-linear?

PS. for sure almost anyone on here can make their own line cord using "good" parts - but figure out the actual cost of materials, premium materials including the aesthetic finishing stuff, add it up report back and then multiply that by 5, that is your retail price. It won't be as low as you think. Thus, a few hundred today is reasonable.

Much more unreasonable than your run-of-the-mill IEC power cable, available at any hamfest for a quarter or so...

John, yes a fuse is non-linear. Especially where the current is a significant
percentage of the rating. You can find the measurements in Borwick's book, I think it was called Loudspeaker Handbook, or Headphone Handbook, not sure, but it covered things like the fuses and the workings of the Quad ESL 63 speaker design... you can skip the glass, it is still non-linear.

EDIT: here it is: http://www.amazon.com/Loudspeaker-Headphone-Handbook-Third-Borwick/dp/0240515781

Doubt if you will find many 12ga or 10 ga IEC power cables at a hamfest. I'd not be running my 100 watt class A amps on an 18ga. IEC power cord since they draw ~800watts from the wall sitting around... that is, IF I was running a set of 100watt class A amps. My amp only draws around 300watts sitting around, more on peaks... and my amp doesn't use an IEC connector, but that's another story. And it doesn't use 3AG sized line fuses either. And it has no +/- rail fuses. But that too is another story.

                      _-_-bear

[WA1GFZ]

Walt did you ever deal with Glenn Glenn, Holywood sound guy from way back?
He had some interesting methods

[WA1GFZ]

Litz wire sucks in switcher transformers. poor thermal

[W2DU]

No Frank, I never dealt with Glenn Glenn, but I was familiar with the name .

Walt

[w3jn]

Wow....