[sdiy] Brain filling in fundamental

[Andre Majorel]

On 2008-07-19 15:48 +0100, cheater cheater wrote:
> On Sat, Jul 19, 2008 at 8:22 AM, Andre Majorel <aym-htnys at teaser.fr> wrote:
> > On 2008-07-16 20:47 +0100, cheater cheater wrote:
> >
> >> Isn't it that under a certain frequency certain to the object in
> >> question objects will stop vibrating at the fundamental but
> >> still 'pretend' to vibrate? Excuse my terrible language here,
> >> I'm not even sure how to explain this properly. I do believe
> >> that this is a less or more known phenomenon...
> >>
> >> Isn't that why electric bass guitars sound this 'harsh'
> >
> > Harsh ? When unamplified, you mean ?
> >
> >> - because the guitar body itself would have to be much larger to
> >> 'house' the fundamental?
> >
> > The problem is that the "diameter" of the small body is small
> > compared to the wave length of 41 Hz in air (8.3 m) and as a
> > result, it is not good at making the air around it vibrate at that
> > frequency.
> >
> > Now, if you place your head against the body of an electric bass,
> > you'll hear a very strong fundamental. Making contact with the
> > body eliminates the impedance mismatch at the body-air interface.
>
> so you're saying this is merely a mechanical impedance mismatch?

Acoustic impedance mismatch, yes. But please don't bet your house on
that being the correct explanation. I'm not an acoustician, just a
random synth lover who spends too much time reading rec.audio.pro.

> Same reason why the rotary woofer works as well as it does?

Er... You've lost me there !

-- 
André Majorel <URL:http://www.teaser.fr/~amajorel/>
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