From tande.adamson@btinternet.com Thu Jan 08 17:49:12 2004
Subject:Re: Leslie tone better than Motion Sound - why?

> Early Leslie cabinets made by Calcraft were veneer lumber core
plywood, a
> wood product available only as "special-order" these days.
The "core" was
> usually a less expensive hardwood like popular or birch. Later
Leslie cabinets from
> Swiss Plywood were/are veneer covered MDF. Leslie cabinets are not
> necessarily created equal.
>
> Harvey Olsen

>
> [Non-text portions of this message have been removed]

I don't know whether this has been mentioned before but aside from
veneers, glues, MDF, sounding boards and the rest, from what I recall
from memory, the resultant sound from an instrument or sounding
device has a lot to do with the thickness of the aperture from which
the sound emanates.

Hi Fi manufactures are at great pains to put their loudspeakers in
cabinets which neither resonate nor provide a tunnel for the outgoing
sound waves, using surface mounting. Also tested some while ago by
What Hi Fi mag. was the effect of putting speakers directly at the
side of a TV., against the sound when the set was taken away, where
there was less colouration. Loudspeaker cabinets are often rounded or
bevelled to reduce exit point diffraction effects.

By contrast the sound emanating from even a stopped Leslie has to
negotiate the tunnel of the drum in the case of the bass, the horn in
the case of the treble, and also the louvres in the cases of both
treble and bass. The louvres are fairly thick. This I believe has a
lot to do with the sound tone.
This is similar to the wooden tibia pipes which sound mellower than
metal flute pipes which is due in the main to the thickness of the
sound waves' exit point rather than the material itself. Pianos have
been made of clear perspex with wooden sounding boards and sound fine.

In the case of instruments like guitars, violins, pianos etc., they
need a sounding board to amplify the sound and it is of great
importance that the material should resonate sympathetically.
Electric guitars don't need this resonance, being electronically
amplified, and so could be satisfactorily made from a number of
materials.

Leslie cabinets, whilst not built to Hi Fi standards don't need to
resonate either. Some resonance is a given, as there is no use of
damping material to reduce resonance and plenty of internal
reflecting space to encourage it. So I could easily be wrong on this,
but I still doubt though that one could, with certainty, pick out a
plywood Leslie from an MDF Leslie ( or even perspex )from their sound
alone, where all other components were identical. Of course a plywood
Leslie should be much better able to withstand the rigours of regular
transporting than one made of particle board.

Each component part is important to some extent for the end result of
course but maybe cabinet material is one of the less important
factors regarding sound.

I have a Nord Electro which no doubt would sound better to some if it
were black with wooden end cheeks :-)

I haven't the necessary experience of having worked with, or lived
with a great variety of Leslies, so real life experience is lacking
to some extent, so if the above is entirely wrong I'm making
appropriate duck and dive preparations.
Thomas.