A challenge to the "measurement" camp
phcollie I think it is a waste of time and effort explaining to someone that they are wrong. >>>>>People can be so stubborn. 😬 |
.... and yet people have made antennas out of liquid metal almost exactly like the material claimed to be used in the Teo-Audio cables and guess what, those antenna have a characteristic inductance, why, because any time you have two conductors in proximity you will have inductance, period, end of story. This article is from 1995 and is as wrong now as it was then it its conclusions and methodology. I wouldn't say that the article "nailed" anything, except perhaps to illustrate what actual engineers have been saying all along, that LCR parameters are what matter, not all manner of made-up voodoo. But let's talk about the bad engineering in the article. A sine-wave tone burst is "Not", big emphasis on "Not" only inclusive of that frequency. The waveform as presented has near infinite frequency harmonics, which is required to start and stop a waveform instantly. Let's unwrap this statement, "The other wilder, more wavy response is the imperfect damping measured at the speaker end. The different responses directly show each of the cables' ability to aid the action of the amplifier's NFB". This makes the assumption, not correct, that high damping leads to best sound. Arguably, lower damping can lead to less distortion. But again, the point is taken, that LCR, particularly L, and not some made up specification, is what matters. What can't be stated unequivocally is that high or low is best, at least not for a single run, and not for any given speaker and speaker/amp combination ... or was it really L?? 0.5mm twisted lamp cord will have less inductance than 1.0mm twisted lamp cord (normally) because you can keep the conductors closer together which leads to less inductance. Resistance is higher. So those 1KHz waveforms are not measuring the impact of L, they are measuring the impact of R .... and in many ways they are measuring things not at all about the cable, as the frequency of the oscillation is independent of the cable. The 15Khz tone has oscillations at 100KHz approx, all amp/load induced as the same frequency as the cable and low and behold, the oscillations match ... NOT the L, but the R most closely (as I predicted above). The author may not have predicted it because he is not a good engineer. Surprisingly at such a high frequency, some of the fat, low-resistance cables are damping best—if not in the order one would predict from their CSA: At 125Hz, oh look at that, pure resistance based results. |
