I can't afford wasting time to follow up your subjective and anecdotal by-the-ear proof, unless you'd like some subjective and anecdotal explanations about this subtle influence.
Hi Dan,
RG-59 is a curious choice for running an audio signal through. It's large and stiff due to the solid copper center conductor and wouldn't be my choice. RG-58c/u has a stranded core, so more flexible. It's used in many lab applications for running signals and I do use it on some of my audio test equipment for patch leads to audio equipment. Of course I also use it for running RF signals too. You could try RG-174 (and other related cables) as it has a small diameter and is very flexible. I use this inside some RF equipment and for test leads. It has higher loss at high frequencies, but this should not affect the audio signals unless you are using it in a high impedance circuit. If so, the either use a buffer to drop the impedance, or if inside equipment, try straight non-shielded hook-up wire like the rest of the audio industry at line levels and impedances.
Beyond those circumstances, I can't see you hearing a difference in shielded wire by removing the outer jacket. Not unless some gross connection like shield to chassis contact is happening! But under normal circumstances, removing the outer shield will not affect the signal in any way. That means I strongly doubt you are actually hearing a difference bu removing the outer jacket. Sorry, but the science of physics - electronics is against what you are suggesting. Confirmation bias would be my guess.
-Chris
There is only one instance why this could even be remotely possible. If you ran a high impedance signal source on both ends using the shield instead of the center conductor, then ran the cable across a metal surface that was connected to some potential that was related to system ground. In that case the signal is routed through a capacitor with different characteristics in the dielectric. When the signal runs in the center conductor, the shield forms the other plate of the capacitance, but shields it from other conductive surfaces (unless the cable shield is really bad). In that case, removing the outer jacket will only allow the shield to oxidize over a period of time. That might affect the shield which might affect the capacitance slightly. but over time. It would probably be inaudible.
RG-59 is a curious choice for running an audio signal through. It's large and stiff due to the solid copper center conductor and wouldn't be my choice. RG-58c/u has a stranded core, so more flexible. It's used in many lab applications for running signals and I do use it on some of my audio test equipment for patch leads to audio equipment. Of course I also use it for running RF signals too. You could try RG-174 (and other related cables) as it has a small diameter and is very flexible. I use this inside some RF equipment and for test leads. It has higher loss at high frequencies, but this should not affect the audio signals unless you are using it in a high impedance circuit. If so, the either use a buffer to drop the impedance, or if inside equipment, try straight non-shielded hook-up wire like the rest of the audio industry at line levels and impedances.
Beyond those circumstances, I can't see you hearing a difference in shielded wire by removing the outer jacket. Not unless some gross connection like shield to chassis contact is happening! But under normal circumstances, removing the outer shield will not affect the signal in any way. That means I strongly doubt you are actually hearing a difference bu removing the outer jacket. Sorry, but the science of physics - electronics is against what you are suggesting. Confirmation bias would be my guess.
-Chris
There are lots of things many people can't discriminate by taste alone i.e. blindfolded.
- Why would anybody run the hot through the shield? That's not cable directionality, that's a bad/incorrect cable. Directionality is swapping the ends of a good/correct cable and hearing a subtle difference.
- RG58 is likely a poor choice for audio. These are still RF cable, and the shielding is matching the RF shielding requirements. That is, the shield mesh (if a mesh at all, I've seen RG58 cable that use a layer of wrapped wires only) is too sparse to be an effective shield at low frequencies. RG59 (75ohm), while indeed rigid, could be much better audio cable, if it uses a layer of aluminum foil under the mesh.
- RG174 is indeed thinner and much flexible, but having a sparse shield mesh could be as worse as RG58. As another minus, it has a teflon core insulator which make this cable prone to kinking, which will degrade the shielding efficiency (both at LF and RF).
The cable external dielectric could be polarized by the electric field; as such, the electrons spin in dielectric are orienting parallel with the electric field and the quantum effect is an interaction between the spinorial polarization field and the magnetic field, resulting in a coupling that may affect the TEM signal propagation in the cable. The audible effect will be usually a smearing of tonality, but an increased sibilance of female voices is also possible, at least this is what the Klein-Gordon equation is predicting.
See, it took me less that 5 minutes to explain this subtle difference.
Dan, what is your claim in this matter again, if you would please?
What is the cable doing, carrying digital or analog, how long is the cable, what is it connected to at the ends, is the uninsulated braid touching anything, etc.?
If it is typical braided shield removing the outer jack would move things a bit. If there is a foil or conductive costing on the jacket that would also change things.
Is it mil spec RG or a namesake commodity. I usually used quad shielded RG6 for TV drops, but it really doesn't meet the actual RG6 spec!
So more detail would be required. But I suspect careful measurements will show something.
In stadium wiring, as soon as the electricians start pulling my cables, I like to run measurements and point out to them when they did something wrong like pulling out a twist. Mention what they did and where in the run they did it, seems to keep them on the straight and narrow path after that.
Might be an explanation … another might include that the black outer jacket contains black pigment from a substance which aids in shielding.. esp at higher freqs. Typically, graphite and carbon.
-RNM
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I will be doing a similar same thing to a Lenco L75. Partly because it is a 50hz motors, but also because the secondary winding with a capacitor gets an even more basterdized 50hz than the pre-existing trashed up modern frequency from the wall. But I won't be done nearly as soon, I am sure. I have to get a plinth etc etc. Point being is if you can't score a 60hz motor, grab a 50hz one and make a speed controller. Some turntables have a lot more euro parts avaliable.
The TD-160 used a 115V synchronous motor with a phase cap on one winding (external to motor). I am building the SG4 speed controller which generates two sine waves, one delayed by 90 degrees; the phase difference is variable as is the frequency and voltage. It drives a pair of Class D amplifiers, which in turn drive a pair of step-up transformers to drive the two motor coils.
I think the 126 had an electronic speed control driving a low voltage AC motor, but I would need to check. The motors are becoming unobtanium, so if the motor is borked this project won't help. But take a look at Pyramid's thread in "analog source" about a similar drive for BLDC motors. If you could find one that would physically fit (or could be made to) it might be a nice solution.
I would love to see someone produce a high quality AC sync motor that could be used in these fine old tables, as they are slowly wearing out and burning out and are very hard to repair. A couple years ago a Swiss guy on ebay was advertising some NOS motors forThorens TD-160/150/145 etc for about $100 a pop, which seemed high, and now I wish I had grabbed one for insurance.
Hi Mark.
The scenario is CDP or USB DAC connected to Denon receiver via 40cm interconnects constructed of RG59 and el cheapo (white) RCA plugs.
Denon is two wire power cord, Netbook/DAC running on internal batteries, CDP is running from Laptop SM PSU brick that has earth thru connection.
The interconnects form a 180* loop between source and amplifier mounted on adjacent equipment rack shelves, braids are not touching each other or anything else.
Result is same/similar regardless of source.
I make two claims.
1 - The interconnects are directional (subtle effect).
2 - The interconnects are directional with the outer sheath removed and the system sound is different with the sheath removed.
Reversing both interconnects causes a change in the low level system excess noise/ambient information sounding not unlike reversed absolute polarity.
Reversing one interconnect causes a change in the low level system excess noise/ambient information sounding not unlike one channel reversed absolute polarity.
The subjective manifestation of reversing one cable causes a broadening of mono center information and broadening of depth of mono central information, IOW increase in uncertainty of Mid information/decrease in 'focus'.
I did run some testing/recording yesterday and I got something...today I will run a slightly different method and see what I get.
Dan.
Thanks Waly.
The tonality change that I noted caused by removing the sheath was to remove a slight 'bump' in lower mids/mids and overall slightly clearer and sounding more 'correct'.
Tomorrow I will refit the sheath and take a closer listen and let you know what I find.
Dan.
That's what you get if you do it:
< This "Beautiful Woman Soldering" Stock Photo Is Awful | Make: >
But ours are not that kind. One is even qualified to solder stuff that goes to space,
which I must not do, not even for my own designs. But the world there ends at 0603.
(The wording was actually absolutely common in a top 10 semi manufacturer,
albeit not with soldering but bonding, and without negative connotations.)
I would not complain if a mod removed the sub thread.
Hmmm, I have observed change in 'tonality' according to colour/pigment of otherwise 'same' AC power cable.
Dan.
Hi Ed,
If the shield expanded slightly, it would reduce the capacitance, but do you think it could create some kind of frequency dependent filter? I would think that changing the capacitance may affect the time constant against the impedance of the circuit, but if it reduced the "hump" in the mids, it would also drop the level of the higher frequencies as well. Low pass filter like.
-Chris
Thanks, didn't think of that actually. But Dan just reported that he will pull the jacket back on. If that is possible, I can't see the cable retaining any of it's characteristics in normal use. There is no way the jacket should be able to be put back on.
If the shield expanded slightly, it would reduce the capacitance, but do you think it could create some kind of frequency dependent filter? I would think that changing the capacitance may affect the time constant against the impedance of the circuit, but if it reduced the "hump" in the mids, it would also drop the level of the higher frequencies as well. Low pass filter like.
-Chris
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