Colossal wrote: ↑Tue Aug 16, 2022 11:30 pm
No, it should not be taken in this sense: I always read Martin's posts with great attention and respect and I am aware of his skills!
But I also think (?) that he has a sense of humor and since he ended his post with "so a relatively small movement of the player would reverse the effect", I thought he was heckling me, that he wanted me to understand that it was very subtle and very difficult to explain.
that's all, I did not in any way want to disrespect him OR to neglect the effort of explanation that he wanted to bring me!
(sorry if I expressed myself badly ,but English is not my native language and is quite complex and subtle!)
I understand. My apologies then.
no need to apologize ... I understand your reaction !
my English is so approximate and therefore my ideas not always well transcribed! (And I also hope Martin Manning didn't take it the wrong way!)
j0k3335 wrote: ↑Wed Aug 17, 2022 1:12 pmI hope you didn't take my first answer the wrong way! I appreciated that you took the time to try to explain to me! :wink:
On the other hand, finally, I was a little in the truth on the fact that you were a little skeptical on this phenomenon. :?: :)
Thank you for those final details. :wink:
José :wink:
No worries José. The true meaning is often more than the words alone.
j0k3335 wrote: ↑Wed Aug 17, 2022 1:12 pmI hope you didn't take my first answer the wrong way! I appreciated that you took the time to try to explain to me!
On the other hand, finally, I was a little in the truth on the fact that you were a little skeptical on this phenomenon.
Thank you for those final details.
José
No worries José. The true meaning is often more than the words alone.
thank you for your understanding (... and your humor too finally! )
José
pdf64 wrote: ↑Wed Aug 17, 2022 7:32 amIf signal polarity made a noticeable difference, wouldn’t polarity flip pedals would be a thing?
It is in signal splitting pedals where you might be driving two amps at the same time.
Absolutely, but that’s relative polarity, whereas my take was that this thread was in regard of absolute polarity?
martin manning wrote: ↑Tue Aug 16, 2022 7:14 pm
One difference is in the initial attack. When the guitar string moves from the treble side to the bass side it produces a voltage at the jack that is opposite in polarity to the voltage produced when the string moves from the bass side to the treble side. This is due to the change in in the magnetic flux passing through the coil being reversed. The initial voltage that appears when the string is released by the pick causes the speaker cone the move in one direction or the other, either pulling or pushing the air in front of the cone, depending upon the phase relationship of the output to the input of the amp. …
One aspect of that which people may be overlooking is pickup polarity; the point being that it varies, there’s no absolute industry standard, and with some arrangements, eg the Peter Green Les Paul, signal polarity will change according to the settings.
And if a guitar is reconfigured from right to left handed, does its signal polarity (ie how it responds to a downstroke) change?
Last edited by pdf64 on Thu Aug 18, 2022 10:11 am, edited 1 time in total.
j0k3335 wrote: ↑Tue Aug 16, 2022 3:50 pm
Would someone be willing to waste a little time to give me the beginning of an OBVIOUS THEORETICAL explanation!
... which my level of knowledge does not allow me !!!
of course there is difference. on positive impulse of amplitude coming first, speaker moves forward, and on oposite, negative first, moves backward. first sound is coming in front of the speaker, in second case, start to move initially IN the box, out from you.
bepone wrote: ↑Thu Aug 18, 2022 9:50 am
of course there is difference. on positive impulse of amplitude coming first, speaker moves forward, and on oposite, negative first, moves backward. first sound is coming in front of the speaker, in second case, start to move initially IN the box, out from you.
j0k3335 wrote: ↑Thu Aug 18, 2022 10:13 am
That's some more infos ! Thanks a lot
José
no problem, check on the graph, several peaks are shown. those are speaker cone movement. raising one direction, to OUTSIDE, extending, falling opposite, to INSIDE, retraction.
in this example, rising peak has 1.4V amplitude, falling (second) has 0.8V amplitude. so in one speaker polarity TO YOU, in front, is coming the wave of 1.4V amplitude, and if you reverse polarity, to you in front is coming the second peak, falling , which is 0.8V. the first one 1.4V is now shot behind the speaker, in the cabinet, and it is considered like "waste wave".
bepone wrote: ↑Thu Aug 18, 2022 9:50 am
…
simple speaker impulse response is showing that.
..
Aren’t IRs based on a positive pulse though?
I’m not sure there’s a certainty that the result from an equal but opposite negative pulse would be a mirror image?
Due to the cone’s movement perhaps being different one way than the other.
martin manning wrote: ↑Thu Aug 18, 2022 10:44 am
…
My point was that you only see that kind of thing when there is one signal source and multiple drivers.
Ah, yes, ok.
Isn’t the polarity switch in signal splitting boxes is usually a toggle or slide type though, rather than a footswitch, ie something that the player could easily use to make an AB comparison of one polarity to the other whilst playing?
The problem I have with all of this is that it does change the sound with a single speaker. This tells me that as of yet we don't an explanation for it.
CW
in medicine, they demonstrated that the action of a placebo is not only psychological BUT also physiological (at that time they even introduced the notion of NOCEBO!).
So am I the victim of a placebo effect with this effect that I "think" I hear?!
... in any case I do not take out the soldering iron and it stays plugged in that way!
bepone wrote: ↑Thu Aug 18, 2022 11:51 am
…
in this example, rising peak has 1.4V amplitude, falling (second) has 0.8V amplitude. so in one speaker polarity TO YOU, in front, is coming the wave of 1.4V amplitude, and if you reverse polarity, to you in front is coming the second peak, falling , which is 0.8V. the first one 1.4V is now shot behind the speaker, in the cabinet, and it is considered like "waste wave".
That all seems a bit wonky to me
The rationale of the above seeming to be that we hear negative pressure fundamentally differently to positive pressure, even to the point that, to paraphrase, negative pressure is just waste, only positive pressure matters?
)
