Well, do you know anything about specialized made by companies like Gore for military-industrial applications? If not, you should.
Ed Simon wrote a paper, that I think was in Audio Express, late last year. Figure 5 shows the effects of cable directionality, and the commentary gives his subjective impression. This is how we do in in audio design. (for better or worse )
Well, I know about Super Corr-B and you may want to know about that . . .
Effects of Corrosion Inhibitive Lubricants on Electronics Reliability
What are your thoughts on null tests?
Through anealing process the latest Ohno casting copper (occ-A) is much softer and much less sensitive to bending etc.....
I can only guess, but it was probably because he didn't measure "the whole picture" 🙂
If he measured in room power response he would have probably noticed lack of energy around crossover point caused by the directivity of bass/midrange driver. By lowering crossover point he assigned that part of spectrum to a upper driver which had much less directivity at those frequencies. So he corrected power response and got better sound. 😀
I would hope that individuals not exposed to quality wire as a rule would look at the Gore selection of wires, and even note their prices. This is the sort of thing that is necessary in laboratory and military applications.
AudioXpress “Distortion Meter,” Ed Simon, Nov. (2009), p. 22
"Figure 5"
An externally hosted image should be here but it was not working when we last tested it.
Looks like Ed wrote interesting articles and that AudioXpress has a new digital version.
AudioXpress
Let's take imaging for example. You want to measure the delay between the right and left speaker at listening position & the early or late reflections within the haas window. One thing that can have a negative impact on imaging is early reflections, because your brain starts a clock when it receives the initial sound, for a brief moment after that period the sound is summed, and anything after that window is interpreted as reverb or echo depending on the delay. Speakers will sound crisper and imaging will sound better when you hear the main wave before the reflections. It's why speakers sound better away from the wall facing you and why you place dampening material at the first reflection points. If you make adjustments to the speakers positioning to correct imaging (instead of using room treatments) you'll also be adjusting the nodes excited in the room, and this should be taken into account as well. There are other small things you can test for, but it depends on the results you're seeing.
Does this mean you can't achieve proper imaging with out a calibration mic? No, that's not what I'm saying. I'm saying just like other aspects of sound, this isn't something that can't be identified with a microphone. If I'm positioning a pair of mains I'll start with the position that's mathematically more likely to produce ideal results, then I'll adjust the speakers several times getting the listeners impressions, marking positions that produces positive results. Finally I'll compare positions on paper to see which ones are the easiest to tame the acoustics for. Looking to avoid large nulls or peaks that can't easily be corrected and positions which don't produce a reflection nightmare. My long winded point is it is possible if you know what to look for.
It would be cool to start a thread outlining measurements and their relation to the environment, the hardware and what's possible to hear. You can setup speakers and make adjustments that'll impact the imaging, like adding and removing dampening to the rear and first reflection points and seeing how it impacts the measurements. Begin to understand the relationships between sharp points on waterfalls and masking. How to identify early reflections or how to use different waves for testing purposes. How to reduce resonance from creating ringing or booming. How to identify different types of distortion, echo/reverb, what are natural dips and peaks and what are nodes & antinodes. Even if people know some of this, it would be good to have it outlined somewhere. A lot of this stuff can be understood with simple trial and error and a little bit of reading, tho some things can be a bit complex.
One final note before I pass out. There seems to be this idea that if measurements can't be used to select a speaker than measurements might not be capable of seeing differences in speaker wire. The problem with this idea is even if measurements didn't provide a good way to compare speakers, it's not the same as saying speakers will measure identically. I don't know any 2 models of speakers that measure identically in the same environment yet sound completely different. Every driver I've ever seen measured has different CSD and distortion even if their FR are similar. Trying to claim 2 different speakers with different drivers or crossover designs will measure identical and sound different just goes to show a lack of understanding of the subject. If speaker wire made any difference there would be some way to identify it, period.
Nicely written.
I have never been a "believer" in either religion or cables (basically the same thing). I used to accept that my lack of religious beliefs was personal and I just kept it quietly to myself. Having read a lot about problems in the world, I have concluded that we (the non-believers) can no longer keep to ourselves while the radical religious beliefs of others stand to jepardize the whole worlds stability. So I am not so quiet about my beliefs of religion and its intollerance. If believers want to profess their ridiculous position arround me then they need to be prepared to be attacked regarding the shabby ground on which they stand. This is equally true for both religion and cables.
I wish you well on your operation - we need you back here.
I am not going to give a treatise on this topic, but some review is in order.
Lets look at the issues:
You refered to "thermal compression" which I see as equivalent to "dynamics". There are no standrad tests here, but I have done several tests of the thermal properties of different loudspeakers and they are highly variable and significant. This needs to be standardized and better quantified, but its not black magic.
"Imaging" is more complicated because it involves the room and how the loudspeakers interfaces with the room. Just looking at an axial response is not going to tell you anything about how the speaker will inteface with the room, you need to look at the entire polar response. It needs to be well controlled both on and off axis AND fairly narrow.
"Spatiousness" is clearly another property that is more the room than the loudspeaker so there aren't many loudspeaker measurements that are going to tell you much about this, although InterAural cross correlation has been shown to be highly correlated with the perception of spaciousness.
I don't remember the other characteristics, but the point is that these things CAN BE quantified and that very few show you data which is going to be useful in this context. But to say that these things cannot be quantified is not true - "do not" is not the same as "cannot".
There are some fringe issues in perception that have not been resolved - "dynamics" comes to mind as not fully understood, but we have learned a lot - like the insignificance of nonlinear distortion in loudspeakers, etc. Basically the two things that are usually measured Axial FR and THD are probably the two least useful measurements that I can think of. No one could tell a good loudspeaker from a bad one with any confidence based on these measures. But with sufficient measures - as described above, I believe that I could tell a good loudspeaker from a bad one with very high confidence just looking at the measurements.
I said this before, a picture like that only begins to suggest things to eliminate. The noise floor is all too familiar, could post some too. There are clearly line harmonics "exact" placement in each case is important. The stuff around 3k can be from FL ballasts we get a lot of it with our new lights. Where's the no signal base line with cable dangling on input?
Are those harmonics of 60Hz? Looks like some interference that changes when you put the cable down at a different location.
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