Yes it does! Theory says no, measurements say yes! Now for a small coil it is very small, but for a 500' spool it really is a big difference.
I had a particularly obnoxious consultant, who specializes in ripping off Southern Baptist and other Evangelical churches, take a 1000' spool of microphone cable of mine, put ends on it and use it for his measurement microphone in a football field. He then tried to blame everyone else for the bizarre frequency response curves he got.
But if it spans a football field it isn't coiled up anymore.
I defer to jneutron on inductance measurements but I would think that with a non-match terminated setup the 1000' of capacitance would be more of a problem.BTW we typically don't uncoil 300-1000' spools in the lab (not practical) to test rate and reach on any number of things like video over CAT5, have not seen any issues.
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Question:
How many here connect mains ground to their system ground ?
Not talking about connect mains ground to the metal case - that's a must for safety.
So I could rephrase the question . . . How many people connect their system ground the metal chassis of the cases in the comprising their system.
If you do connect it, do you connect it in one place only or several places ?
For me at present my DAC system ground is connected to to mains ground but my amps system grounds are connected to mains via 100R resistors.
Wondering about the impact on sound quality of different options
How many here connect mains ground to their system ground ?
Not talking about connect mains ground to the metal case - that's a must for safety.
So I could rephrase the question . . . How many people connect their system ground the metal chassis of the cases in the comprising their system.
If you do connect it, do you connect it in one place only or several places ?
For me at present my DAC system ground is connected to to mains ground but my amps system grounds are connected to mains via 100R resistors.
Wondering about the impact on sound quality of different options
Okay, here is the FR of our system. This at the listening position and I'm sure you all have fun with this but it sounds really good. No one in this house hold can hear above 9khz anyway!
14db scale, pretty bumpy ride, how much smoothing ? the high frq roll off is typical when off mic axis ...
as oppose to CD cold .......
But if it spans a football field it isn't coiled up anymore.
BTW we typically don't uncoil 300-1000' spools in the lab (not practical) to test rate and reach on any number of things like video over CAT5, have not seen any issues.
Uncoiled the range would be greater!
To make measurements he never fully uncoiled the spool. Also the spool is metal.
Actually the same consultant specified data cable as it was lower capacitance. Since it was not near 110 ohm impedance it worked much worse. (Look he was a jerk and an idiot. His 2 year technical eduction was as a plumber. He does rake in money as a consultant!)
The cable on a spool issue also shows up on loudspeaker runs.
But that's only because of decisions made at recording time. I have compilations of juke box hits on CD from the 50's, etc - and the tracks absolutely ooze that period - you can smell the valves, the oil of the tape deck motors, the milk shakes in the hands of those listening. Some of the crooners' tracks are so dripping of the land of milk and honey you could skip a meal from the calories in the air ...as oppose to CD cold .......
I'll let jneutron answer this, otherwise let it pass. As usual we have to guess just what the issue is.
Some of the crooners' tracks are so dripping of the land of milk and honey you could skip a meal from the calories in the air ...
That would be the RCA ribbon mics. I take exception to some of your generalizations. I have heard 30's recordings on FM that have made me pull off the road to listen and some 40's Cab Calloway that have surprisingly little noise and distortion.
Or you could just listen to a loudspeaker through 250' of cable on a spool and then try it with the cable off the spool.
But my spools are wooden (they float too), and I would think 250' speaker cables would have plenty of different problems. You need to sort them all out, I know only so much time in the day.
500' of 0000 welding cable now that's getting up there in audiophile land in price, but think of the impressive heft.
You can use a wooden spool. Besides the electrons getting dizzy from going in circles what else do you expect to change between spooled and unspooled?
Thank you for defending my post. The coil was about 250 ft if I remember my est. at the time . This was on the mics out in the theater about 2/3 of the way back from the stage.
Been there done that , horrible mid/top , made everyone sound short and fat..
That's too bad, I would have thought there is not much better for 1 Ohm speakers (50uOhms/ft).
The mic cable is shielded and the speaker cable isn't, that makes no difference? I'm sorry I don't have a large enough listening room to unspool 250' of speaker wire.
As I said from measurement shielded spooled twisted pair measures the same characteriastic impedance i.e. inductance per foot as unspooled within a small error. As usual numbers and mechanisms please. BTW a large inductance to commn mode signals would be a good thing IMO.
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I thought the same too, I'm using solid flat .5 inch wide copper now , happy with the results so far. When used on the bass driver it was better (6ohm load) , so i"m using it on bass duties ...
Except, I cheated! Separated the audio, upsampled to 192/24, this suits the PC/DAC better - ensures that the vocals are totally clean.
However, yesterday I was getting clean sound, today it's a bit sludgy - what's going on?? What's different ... okaaayy ... got Windows Explorer open, and an audio CD in the drive - take CD out, close Explorer ... aahh, that's better!! Even though many people pooh pooh processor activity affecting things, this can easily be the difference between the sound being acceptable, or not - with 'difficult' recordings it's very much "everything matters" territory ...
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