Agreed, Vacuphile. The bitter reality is that many high end outlets make their money with accessories
including cable and they have to survive somehow.
I still think lobbying for sound quality makes sense when we do not want that whole scene
brakes down. Every movement has an anti movement. People get bored over time and want something better or more exiting.
Concerning how flat a frequency response must be i constructed several "virtual" speakers in LSP-CAD. An impulse response can be derived and the music "folded" over it. I could not hear better then plus-minus 2dB provided that the octave to octave balance was flat and there are no sharp peaks in the response. What was audible was the general trend. Look what Linkwitz is doing. He claims that he can hear tiny changes in the equalisation of the tweeter in the Orion. Fractions of a dB in the range around 2.5 to 5Khz where the ear is most sensitive. What i could also hear immediately when i truncated the response under, say, 50Hz. I would say that most systems out there really suffer from a loss of bass level and quality.
including cable and they have to survive somehow.
I still think lobbying for sound quality makes sense when we do not want that whole scene
brakes down. Every movement has an anti movement. People get bored over time and want something better or more exiting.
Concerning how flat a frequency response must be i constructed several "virtual" speakers in LSP-CAD. An impulse response can be derived and the music "folded" over it. I could not hear better then plus-minus 2dB provided that the octave to octave balance was flat and there are no sharp peaks in the response. What was audible was the general trend. Look what Linkwitz is doing. He claims that he can hear tiny changes in the equalisation of the tweeter in the Orion. Fractions of a dB in the range around 2.5 to 5Khz where the ear is most sensitive. What i could also hear immediately when i truncated the response under, say, 50Hz. I would say that most systems out there really suffer from a loss of bass level and quality.
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SY, i know that it is old news but good news. I thought that my graphs where a bit easies to digest then the paper you refer too. I found nothing unusual, taking the noise issue by the side, true.
I am myself surprised how many words can be spilled over a non problem. It is easy to find good cables when you know what to search for and they cost virtually nothing.
I am myself surprised how many words can be spilled over a non problem. It is easy to find good cables when you know what to search for and they cost virtually nothing.
You don't have to satisfy me. I am well aware that when people have something to sell they describe it in the most glowing terms that they feel are appropriate. I have done it myself when I was an IT consultant. There is always a line which we approach. Fortunately many engineers won't cross it. Advertising writers and salesmen don't always have the same scruples; maybe their knowledge is such that they really don't know where the line actually is.
It is interesting I can measure a cable's contribution to a circuit to an accuracy of better than .000001%. When very lucky I can measure a sound source to .25 db (5.9%)!
SY,
Can we talk STADIUM sound systems and 3 db droops. I should be so lucky! I can use up to 10 gauge so a 500' run is around an ohm. Then there were the guys to save on conduit installation costs ran it from the upper deck to the ground level half the length of the stadium and then back up to the roof. About 3000' of conductor per speaker (140 circuits per side) only added about $250K to the wiring cost! Now care to calculate how much extra they pay for power just to make up for the loss... don't forget the cost of extra air conditioning for the amplifiers!
SY,
Can we talk STADIUM sound systems and 3 db droops. I should be so lucky! I can use up to 10 gauge so a 500' run is around an ohm. Then there were the guys to save on conduit installation costs ran it from the upper deck to the ground level half the length of the stadium and then back up to the roof. About 3000' of conductor per speaker (140 circuits per side) only added about $250K to the wiring cost! Now care to calculate how much extra they pay for power just to make up for the loss... don't forget the cost of extra air conditioning for the amplifiers!
True DF96, good thing is that i do not sell cables any more. At least not my own brand. I still stand by my measurements. They have being taken with care and i even produced WAV files so that you could listen to the residuum. They do not contain new information for the initiated. What surprised me how people reacted on this. The one extreme was "Thanks, Joachim, never have seen this, i now understand" the other " You are a pr...,
you sell snake oil". Ultimately this cable business got me frustrated.
you sell snake oil". Ultimately this cable business got me frustrated.
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Nicely said, I hope folks are listening.
BTW Thorsten, I picked up 1000' of Mil-spec PTFE ribbon cable ($10) exactly as you describe but only 10 wide. An thoughts on a configuration of mulitples of it for speaker cables. There's a huge range of L and C values depending on how it's bundled.
Hi Scott,
I think you may need more then one run in parallel to get decent low DCR.
My own way would be:
(+)(-)(+)(-)(+)(-)(+)(-)(+)(-)
(-)(+)(-)(+)(-)(+)(-)(+)(-)(+)
(+)(-)(+)(-)(+)(-)(+)(-)(+)(-)
(-)(+)(-)(+)(-)(+)(-)(+)(-)(+)
This minimises inductance, capacitance in speakers cables is not that critical...
Ciao T
I think you may need more then one run in parallel to get decent low DCR.
My own way would be:
(+)(-)(+)(-)(+)(-)(+)(-)(+)(-)
(-)(+)(-)(+)(-)(+)(-)(+)(-)(+)
(+)(-)(+)(-)(+)(-)(+)(-)(+)(-)
(-)(+)(-)(+)(-)(+)(-)(+)(-)(+)
This minimises inductance, capacitance in speakers cables is not that critical...
Ciao T
It increases capacitance.
The equation will be very close to LC = 3000. L in nH per foot, C in pf per foot.
Figure 1 wire pair as say, 150 nH per foot.
Cheers, John
Thorsten please refrain from making your points using religious or political metaphors, and in particular ones that are blatantly inaccurate. You might want to refresh yourself on recent German history. Further OT posting is discouraged and may result in infractions for those perpetrating same.
To see if I can hear the difference. I usually use #12 zipcord but a short run. Thanks Thorsten, doubling circular mils is about 3 gauges starting at #30 to get to #12 ouch!
BTW big pure copper connectors are standard kit in the US for electricians, I even have some #0000 ones. Solar power web sites often have them in small quantities.
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Scott,
Have fun. do minimise the stress factor. For now assume that as long as the DCR is the same as #12 zipcord, there shoul be no differences. in a few month, change the cables back to zipcord and see ho you like it.
Hence I use the 80 conductor stuff.
Ciao T
Have fun. do minimise the stress factor. For now assume that as long as the DCR is the same as #12 zipcord, there shoul be no differences. in a few month, change the cables back to zipcord and see ho you like it.
Hence I use the 80 conductor stuff.
Ciao T
Isolda Impedance matched cables
Re Post 201. The test shown in the YouTube videos GEOMETRY MATTERS is interesting as it shows what is actually happening. The crucial test is that where the identical copper strips are measured with the different geometry. Careful observation shows that the amplitude of the signal is higher with the cable spaced apart (high inductance, low capacitance) than with the cable closely spaced (high capacitance, low inductance). If the difference signal is amplified and listened to, there is a totally different "sound" between the two. With the spaced test, the sound is not only louder, but it is bright and edgy. On the other hand, with the close spaced test, the sound is softer and far closer to the sound directly through the speakers, exhibiting no edge or hardness. I conclude from this test that the overall sound is better in the latter case.
Yes, we do manufacture impedance matched cables, not because it is some mystical nut case fringe activity, but because it works. We have used impedance matched cables since the late 70s (monitor audio litz) and other variants as well (original Isolda) and every time there is the same increase in fidelity. Once you have lived with this cable, you can't go back.
We have tried hundreds of cables, including the variants described in this forum, but no configuration equals the Townshend preferred geometry. You are free to choose whatever cable you fancy, but, we can guarantee that you will prefer impedance matched cables when the rest of your system is up to it. Ensure that you are not the speaker cable as a tone control to hide other faults in your system.
Isolda cable has a network at the amplifier end to compensate for stability design mistakes in the power amplifier. If your amplifier can not handle this cable, get a better amplifier!
Re Post 201. The test shown in the YouTube videos GEOMETRY MATTERS is interesting as it shows what is actually happening. The crucial test is that where the identical copper strips are measured with the different geometry. Careful observation shows that the amplitude of the signal is higher with the cable spaced apart (high inductance, low capacitance) than with the cable closely spaced (high capacitance, low inductance). If the difference signal is amplified and listened to, there is a totally different "sound" between the two. With the spaced test, the sound is not only louder, but it is bright and edgy. On the other hand, with the close spaced test, the sound is softer and far closer to the sound directly through the speakers, exhibiting no edge or hardness. I conclude from this test that the overall sound is better in the latter case.
Yes, we do manufacture impedance matched cables, not because it is some mystical nut case fringe activity, but because it works. We have used impedance matched cables since the late 70s (monitor audio litz) and other variants as well (original Isolda) and every time there is the same increase in fidelity. Once you have lived with this cable, you can't go back.
We have tried hundreds of cables, including the variants described in this forum, but no configuration equals the Townshend preferred geometry. You are free to choose whatever cable you fancy, but, we can guarantee that you will prefer impedance matched cables when the rest of your system is up to it. Ensure that you are not the speaker cable as a tone control to hide other faults in your system.
Isolda cable has a network at the amplifier end to compensate for stability design mistakes in the power amplifier. If your amplifier can not handle this cable, get a better amplifier!
Between what points is the difference signal measured? Or are you measuring the signal at the speaker with each configuration, then subtracting the signal at the amplifier end? Your description is a bit ambiguous.
What is the magnitude of the test signal and the detected difference signal?
Many thanks.
Could you clarify what you mean by "impedance matched cable"? The speaker isn't a fixed impedance, even if it is somewhere vaguely in the region of 8ohms over most of the audio range. The cable, unless made using a superconductor, is likely to vary even more as for much of the audio range resistance will dominate over inductance so its characteristic impedance will be strongly frequency dependent and not a pure resistance. Do you perhaps simply mean a cable whose impedance at any frequency is somewhat lower than a 'typical' speaker cable? I can see a minor advantage in this, although the difference it produces is likely to be much smaller than the difference between two different speakers, and even this advantage disappears if the amplifier output and any crossover network do not have a very low impedance.
Given particular wires, running them close together will reduce inductance and so reduce the voltage drop at higher frequencies. LF won't change much, as resistance dominates there. As I said in an earlier post, potential dividers divide potential. A voltage drop dominated by inductance will sound bright as it has more HF. One with the same resistance but less inductance will sound less bright (and quieter). This is predictable from simple EM and circuit theory, so I'm pleased that "careful observation" confirms the theory.
Given particular wires, running them close together will reduce inductance and so reduce the voltage drop at higher frequencies. LF won't change much, as resistance dominates there. As I said in an earlier post, potential dividers divide potential. A voltage drop dominated by inductance will sound bright as it has more HF. One with the same resistance but less inductance will sound less bright (and quieter). This is predictable from simple EM and circuit theory, so I'm pleased that "careful observation" confirms the theory.
Most amplifiers would handle a pure real 8 Ohms. Have you ever put a speaker on a network analyser? This is not a match terminated system.
The argument of .0005 wavelenghts of cable having characteristic impedance issues is old and tired. 6 - RG58's in parallel haven't seen that in a while. I wonder how it compares to 9 - RG59's.
He's making a cable that has major capacitance. It's gonna cause a hot amp to oscillate when the speaker unloads at high frequency. I'd figure he's got 350 to 400 pf per foot, and 10 nH per foot. Since he can't control the unity gain point of anybody's amp, he has to zobel it on the cable.
Aren't you going to try this with the ribbon??
Cheers, John
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