RE: Turblolid design

["Michelle LeFree" <mlefree@xxxxxxxxxxxxx>]

When I said:
> > ... The top-to-bottom inner dimension of the Turbolids are ~designed~ to
> > be greater on the "left" end of the harp where the low notes are
produced
> > than the "right" end where the high notes are generated.  In this way,
the
> > T'lids are designed so that the inside dimensions of the cover are
"tuned"
> > to the wavelength of the notes created by the reeds directly beneath
them.
>
> On a C harp 3 draw bent is an A, 220 Hz.  The speed of sound is 335
> meters/second.  That makes the wave length of that A note 335/220 = 1.5
> meters or 4 1/2 feet!  Lower notes have an even longer wave length.
> Acoustic resonance is not occurring in harmonica covers.  The dimensions
> don't fit.

I understand the math Sam, but I'd like to know how you explain the
apparently unanimous opinion that Turbolids enhance resonance?

> My understanding of the fat bottom end was so that low reeds wouldn't hit
> the harp covers which happens on some low tuned harps.  It happens on my
> Steve Baker Special in D on the lowest reed.

Interestingly, we both may be wrong about Turbodog's design intent for
Turbolids.  Mojo Red shared (off-list) a comment that he heard from the good
'dog himself, in which he allowed that the shape was arrived at purely for
comfort when holding the harp.  Maybe Dr. Antaki could straighten us both
out on this.  In any case, I don't think there's any disagreement about
Turbolids enhancing resonance amongst those who've tried them, myself
included.

Thanks, Michelle