[sdiy] Resonator type filters

[Mattias Rickardsson]

On 3 July 2017 at 21:04, Bernard Arthur Hutchins Jr <bah13 at cornell.edu> wrote:
> A lot of questions here about how a filter bank is used and what it sounds
> like are addressed in EN116 which I posted.
>
> Basically, if nothing moves, it sounds like nothing: like sawtooth in,
> different complex waveform out - equally boring.  If something does move
> (modulation, starts/stops, live music) it sounds tinny.    I remember well
> listening to music on the radio through the bank, turning the Q up, and
> discovering that the western music sounded like eastern music.  Possibly a
> useful reference comment.

Oh, so it's some kind of longitude modulator then? ;-)

I think this could partly be caused by another side effect than the tinnyness:

Resonances shift the [percieved] pitch of short notes, when the
resonant frequency is a bit off from the note's fundamental frequency.
This is because the partials of a short note are spread out a bit in
the spectrum due to the limited time it exists, and an nearby
resonance can easily ring louder than the expected frequency of the
note. (Just like listening to bass notes in a room with untreated room
modes - the bass gets muddy not only by smearing in time, but it even
gets hard to hear the pitches of the notes - you end up listening to
the strongest room modes instead.)

So perhaps the music got "out of tune" when run through all the
resonances, and it sounded like oriental scales rather than western?
:-)

/mr