Rant:
During World War 2 morse code operators were found to be able to read (decode) signals way below the noise floor. I used to think that this was proof positive that the subjectivist were right and the engineers were wrong. I mean here is something that is proven audible but can't be measured.
But I was wrong again, NASA uses computers to enhance photos by bringing details out of the noise using similar techniques our brains use. In audio a signal can fade away to nothing it doesn't suddenly cease to exist when it reaches the noise floor. If you have a pattern to look for you can find it, with your ears/brain or a microphone/computer.
The difference is that the mic/computer combo is reliable (you can trust it) whereas the ear/brain combo is unreliable and you should not trust it.
Any sound the ear can hear is able to be measured using today's technology.
Am I wrong again?
During World War 2 morse code operators were found to be able to read (decode) signals way below the noise floor. I used to think that this was proof positive that the subjectivist were right and the engineers were wrong. I mean here is something that is proven audible but can't be measured.
But I was wrong again, NASA uses computers to enhance photos by bringing details out of the noise using similar techniques our brains use. In audio a signal can fade away to nothing it doesn't suddenly cease to exist when it reaches the noise floor. If you have a pattern to look for you can find it, with your ears/brain or a microphone/computer.
The difference is that the mic/computer combo is reliable (you can trust it) whereas the ear/brain combo is unreliable and you should not trust it.
Any sound the ear can hear is able to be measured using today's technology.
Am I wrong again?
fredex said:
So, when I listen to a full orchestra, and find that one cable gives one component of the sound (upper register strings) a very slight - but persistent between recordings - "glassy" tone which sounds unnatural. But another cable doesn't.
How do I measure that difference using today's technology?
Howdy, I know I keep harping on Dynamic compression and harmonic distorsion. They seem to be the primary limitation in speaker design. You can use multiple drivers to lower those numbers but that introduces dispersion effects which can be vexing indeed! Until those issues can be resolved, speakers will remain problematic!
Alan Hope said:
Leaving the rocket science to NASA you keep it simple.
Record the electrical output of your amp/preamp whilst using cable A.
Record the electrical output of your amp/preamp whilst using cable B.
Compare the two.
The difference you find is what you are hearing.
Hope this helps
Andre Visser said:No, let me try again
My original remark was based on a suggestion by tc-60guy to measure cable differences with a microphone and speakers. I believe the differences should show on the low level detail and timing of it. Since our ears / brain can seperate low level detail and loud signals and process it seperately, we should perhaps try and do the same to do the measurements.
Since a microphone detect all the signals, we will have to seperate the low level detail from the louder ones electronically, to do such measurements. I believe that won't be easy to do.
Better now?
André
One thing that I know is that the brain can dynamically vary what it determines as noise by sampling below a chosen threshold or direction.
For instance, you sit at a crowded cafe and there are people just behind your head having a conversation. You have your own talks with your friend that sits opposite to you. Although the unknown people's mouths are 30cm behind you, you listen only to your friend who is 1m in front of you. But if by chance the people behind you mention your first name as a reference to anybody with the same first name, you hear it clearly and maybe you turn around too!
I already did Near Field Analog sweeps and distortion sweeps. Driver used, Usher 8945P.
Swapping interconnects did not affect performance in any way at all. SPL and F1,2,3,4 came out EXACTLY the same.
The truth behind it is that your Amp and Preamp doesn't give a slighted DUCK about very minor capacitance and inductance variations between ICs.
Swapping interconnects did not affect performance in any way at all. SPL and F1,2,3,4 came out EXACTLY the same.
The truth behind it is that your Amp and Preamp doesn't give a slighted DUCK about very minor capacitance and inductance variations between ICs.
Originally posted by Andre Visser Post #1311
.............Since a microphone detect all the signals, we will have to seperate the low level detail from the louder ones electronically, to do such measurements. I believe that won't be easy to do.
Better now?
André
It is not as hard as you think. You talk about signals (plural) as if what you are listening to is composed of many simultaneous signals of varying loudness and perhaps frequencies. This is incorrect.
At any one point in time there is just one signal level. This is easily measured to an accuracy far in excess of what our ears are capable. You can record this level over time and see a display of your choosing.
Change a cable or whatever and repeat the measurement any differences will be there for all to see.
But you may not hear them as measurements on audio signals are way more sensitive than our ears.
Cheers
Hello again, I'd like to comment on the relative civility of this thread. Most subjectivist, objectivist debates degenerate into some kind of hissy, spitty, cat fight which ill befits an upstanding audiophile. Because of this, I find myself actually having, dare I say it.......Fun! This is a hobby to me and fun is a golden nugget in my day. Keep it light and keep it respectfull!
fredex said:
Wow - so it's that easy. So has anybody, anywhere, EVER done this?
Presumably, if the 2 signals - one inverted - don't cancel out to null, then there is a difference. And again this thread is over - the subjectivists have won! Because the difference is demonstrably there and a good ear just might be able to detect it.
In fact, thinking about it - the objectivists have won too!
but ...
fredex said:
I agree, all signals add or subtract to form one level at a given time. Is it that easy to detect a signal of a few mV on top of a signal of a few Volt? Remember the frequencies could be close together. Also, I don't think the brain work that way.
I'm quite sure that in CERTAIN aspects, trained ears/brain will be hard to beat with measurements at this stage, just because the brain are able to do much more complex analyzing of a musical signal. Perhaps complex computer measurements that try to simulate the way we hear, will be able to do it.
André
Alan Hope said:
fredex said:
fredex, you took the bait, mate. Wait until there is an iota of evidence that he can in fact hear (not imagine) glassy tones solely due to cable changes -- hypothetical #1 -- before getting sucked into trying to answer his question about measuring it -- hypothetical #2.
While this seems to be reasonable, it is apparently quite often wrong. It is quite unlikely to measure two interconnects with different construction and not to find a difference.
The electrical difference test was at first proposed by Baxandall and Hafler and a modern device for this test would be a decent A/D-converter (or soundcard) combined with Bwaslos diffmaker software (free for use and download at the liberty instruments website) .
This setup will allow for easy comparision of two interconnects and will provide a difference file to listen to.
But in fact, as tc-60guy pointed out, measuring a difference between two interconnects doesn´t mean, the (every) speaker can resolve this difference.
And in the end, even if some speaker do resolve it, it is not granted that the difference is audible.
That´s one of the reasons why proper measurements should accompany any listening test.
@ Thetubeguy1954,
i do understand your concerns regarding the ABX-test (and in fact do not really like it myself), but that is why training and controls are included. Just to see whether a listener does reach the sensitivity level required for the given experiment.
In the end it seems that A/B preference test schemes are somewhat more ´normal´so that most listeners do have less problems to adopt to these test protocols, but there is evidence that others do quite well under ABX.
So it´s up to the experimentator to find out under which protocol the required sensitivity level is reached.
@ tnargs,
That is often stated, but i´m not aware of any evidence for it, if people are listening for complex sonic structures.
Of course you´re right for the difference of amplitude levels and comparable simple aspects.
Most people will do better with rapid switching if looking for differences in pitch, but if a listener does have ´perfect pitch´ don´t need any rapid switching, but it would do no harm.
But If you are looking for the socalled ´sonic fingerprint´in an experiment then rapid switching might even be quite dangerous.
@ janneman,
That would be important and worthwile, but we have to assured first, that the rapid switching method itself doesn´t influence the results.
I mean if rapid switching is just used for convenience then it´s fine, but if your are using it while searching/listening for the afore mentioned complex sonic structures than it can lead to not ´seeing the whole picture´.
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