[Vintage-Audio] Update On AR-4 Info

[WBob]

There is a  lot of hoopla here. Sure the waveforms are not 
symmetric. SO WHAT. move the mic 2 ft and they will have a 
completely different waveform. (think of all those Fourier 
frequencies changing phase differently (2 ft is a diffeerent phase 
shift at every frequency) and then adding back together.

Or if you don't like that, then consider a very short impulse like 
a single drum hit. This has a wave shape that will propagate and 
wander around the room until it hits your ear. I think it may make 
a difference if it is a positive pressure or a negative pressure. 
One makes your head squish and the other makes it explode.

If you get a  audio wave that is anywhere near 14 PSI peak (the 
negative pressure is anywhere near 0 psi), you are within about 
100 ft of a small atomic explosion and the direction of the event 
is not going to matter among the other effects. But there is an 
interesting effect of music changing with altitude (sounds 
different in Denver) and air density (weather).

WBob

Terry Maton wrote:
> Gentlemen
> 
> Some musical waveforms can be asymmetric, even though they are a.c.  This 
> link gives examples, I am sure there are more:
> http://www.st-and.demon.co.uk/AudioMisc/asymmetry/asym.html
> 
> I have heard a test CD that repeats a section of music in both polarities 
> and, yes, it makes an audible difference.  One sounds more 'right', 
> that's about the best way I can describe it.
> 
> The interesting part is when you try and make a judgement about a multi-
> tracked recording where some parts are polarity correct and some are 
> inverted.  (However, with my 'cloth ears' this has never been a big 
> issue..!)
> 
> Cheers
> 
> Terry
> 
> -----Original Message-----
> From: "Rudy Rutenber" <wa6pew@sbcglobal.net>
> To: <vintage-audio@mailman.qth.net>
> Date: Mon, 7 Jul 2003 22:50:29 -0700
> Subject: Re: [Vintage-Audio] Update On AR-4 Info
> 
> 
>>Well, I have to stick my 2-cents in here...
>>
>>Regarding the polarity of the entire system.  When you hear a bass
>>drum, it is positive in that the wave produced at the time of
>>recording, is forward towards the microphone.  If all the polarity in
>>the wiring is correct from the mic to the final medium such as a CD,
>>and, to your speakers, the speaker will move outward and reproduce the
>>bass drum as it was recorded.  In some music, this is not important.
>>In music that has a solid beat or groove, it will sound mushy if the
>>polarity is reversed.  That's one good reason to use the correct
>>polarity for your speakers.  (that is, a positive voltage on the
>>positive terminal produces an outward motion of the cone)  I'm sure
>>there are many others as I am sure to learn here soon.
>>Rudy
> 
> 
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