And how does this become detectable by reversing direction of a passive component that is carrying AC? You need at least 0.1dB change.
Yes, but your ears hear two speakers. It is your PERCEPTION that leads you to believe there is a phantom singer standing between the speakers. The brain sort of 'thinks': aha! I get the same impulses from the L and R ear, so there must be a singer right in front. Which, of course, there isn't.
So you see, the brain can do all sorts of things that have no base in reality 😉
@Nicoch58: could you please help us to understand you better by writing 'hear' if you mean the process and 'ear' if you mean those two things on our head.
I understand English isn't your mother language, so no problem either way, just a suggestion.
jan
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Yes, but that doesn't differ from perception of the reality of a singer placed in the center when you only use ears without sight.
Real singer in front of you: runtime difference zero.
Same level out of two speakers with same distance left speaker/ear right speaker/ear: runtime difference zero.
I still need to read up on HRTF.
Real singer in front of you: runtime difference zero.
Same level out of two speakers with same distance left speaker/ear right speaker/ear: runtime difference zero.
I still need to read up on HRTF.
Hi Dario,
You are heading down one well traveled road, following the foot steps of folks who discover that what they believe has to change to agree with actual reality. Of course there are folks who never get to that epiphany. They become prey from a certain group of people who try to perpetuate these beliefs as fact. You already met a prime predator.
Music is just noise that we like the sound of, and that varies between people. Nonetheless, this signal has no magical properties and follow the laws of physics. The equipment I mentioned much earlier is far more sensitive to signals than any audio equipment is. Just look at the signal to noise figures for spectrum analyzers and network analyzers. It's often greater than 20 dB and can reach levels below -120 dBm in actual real use, not a theoretical noise figure but one is practice.
Audio electronics can be fun, can be capable of very good performance, but it isn't even close to a pinnacle of performance. It's a great diversion for many of us after we have dealt with extremely high performance equipment all day. Equipment designed and manufactured to much higher performance levels than any audiophile not in the industry can imagine. Industrial electronics is not digital.
Some of the highest performing audio electronics were plucked from the design of industrial equipment. The worst examples of audio performance? Gear designed "by ear".
This argument has pulled the thread off into the weeds as happens whenever these arguments come up. It has nearly sunk to the depths of the Blowtorch threads. Too bad.
-Chris
You are heading down one well traveled road, following the foot steps of folks who discover that what they believe has to change to agree with actual reality. Of course there are folks who never get to that epiphany. They become prey from a certain group of people who try to perpetuate these beliefs as fact. You already met a prime predator.
Music is just noise that we like the sound of, and that varies between people. Nonetheless, this signal has no magical properties and follow the laws of physics. The equipment I mentioned much earlier is far more sensitive to signals than any audio equipment is. Just look at the signal to noise figures for spectrum analyzers and network analyzers. It's often greater than 20 dB and can reach levels below -120 dBm in actual real use, not a theoretical noise figure but one is practice.
Audio electronics can be fun, can be capable of very good performance, but it isn't even close to a pinnacle of performance. It's a great diversion for many of us after we have dealt with extremely high performance equipment all day. Equipment designed and manufactured to much higher performance levels than any audiophile not in the industry can imagine. Industrial electronics is not digital.
Some of the highest performing audio electronics were plucked from the design of industrial equipment. The worst examples of audio performance? Gear designed "by ear".
This argument has pulled the thread off into the weeds as happens whenever these arguments come up. It has nearly sunk to the depths of the Blowtorch threads. Too bad.
-Chris
Sorry did not post Marce's comment first re the change in an amplifier after clipping may be due to magnetic effects.
There will be differences in their spectral content. IOW what harmonics and how much of each.
Tool of choice - FFT analyzer, even one of the good software freebies operating on a PC should suffice.
Once the clipping event has finished though the ac current would demagnetise surely...
And how long would the clipping event have to be to magnetise the leads or any other magnetic component.
With today's choice of resistors etc. shouldn't it be possible to design a circuit where the effect of any resistor distortion is so small that the resistors have NO sound or influence on the sound that could be discernible by ear?
I do believe this point has been made earlier...
Yes I think after the clipping whatever happened would revert slowly. My tests hinted it could take weeks! I suspect the clipping actually demagnetizes the transformer core a bit, don't know for sure, but there is a chance that something does change.
Yes again the whole bit about resistor testing is determine what resistors work better than others. Right now my short list is distortion, excess noise, drift and voltage coefficient.
Scott,
Attached are six FFT runs of a 12 volt gel cell across a 1,000 ohm 1/4 watt carbon composition resistor. A switch was used to rapidly switch the direction of current flow. It was switched between each run. Not much change in the excess noise, but the effect is repeatable. Do let me know what you get. (I wouldn't try a metal film with such a simple set up. It is certain to have much less excess noise.)
I think we can rule out micro-diodes as the effect also seems to be influenced by frequency. I consider this interesting but not a real conclusion.
ES
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What effect, what is this a picture of? I see poorly resolved mains harmonics even though you are using a battery. So maybe the two wires make a different pickup loop/antenna. Confounders?
You also need to know every detail of the FFT BW, averaging, etc. to compute the expected standard deviation in the bins.
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Did Johnny the Selfkicker use a Makita or was it still Bosch at the time?
Edit: It was a dental drill. Google 'trepanation'.
Don't try it at home, though.
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Attached is a second version using a low noise preamp so no mains leakage.
All we are looking at is the noise across a resistor when DC is applied. Polarity is changed between each FFT run.
Confounders? Switch, battery, lead length, temperature variations, random noise! I'll run it again in a few days. But if someone else has a battery, resistor, low noise preamp andd FFT they can try it themselves.
4K FFT 64 averages Blackman Harris window. 6 dB repeatably is interesting. No other claims, but it does lend some support to resistor directivity claims at DC. Nothing else.
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Actually it depends on the frequency range of the stimulus- in the range where wavelengths are large compared to the dimensions of ear, head and torso the phase difference gives the directional information but will eventually lead to confusion about front and rear.
It differs from the typical stereophonic setup with two channels as the sound sources are positioned at angles of 30 degree (ref.to the median plane).
As said above it depends on the frequency range, a pure low frequency sinus will most likely be per percepted at "dead center position".
The HRTF allows to extract directional information even in monoaural listening (one ear nearly deaf) if the frequency content is sufficient.
But the subgroup i´ve described seems to be unable to percept the phantom sound source (or virtual sound source)
Today experiments have shown (as was already assumed by Helmholtz and others) that the human listening sense is not a pure FFT analyzer, phase information, envelope and micro fluctuations are playing a role.
DC applied through what another resistor and the battery. Directionality aside there is no, known to me, data that shows lumpy noise spectra from any resistor. I have been reading noise literature for 40yr.
Keeping with the theme, would a Makita battery be the right tool for the job?
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