From bw@ashbysolutions.com Wed Feb 06 08:34:29 2013
Subject:Re: OT: Leslie project

Dennis,

I don't know if there's *intentional* tuning going on there, but if one
builds a sealed cabinet with a speaker, then cuts an opening in it,
there *will* be port tuning going on. The tuning of the port is
affected by the hole size, and by the thickness of the cabinet around
the hole -- even if no actual bass ports are added. I can definitely
hear tonal differences between a 122 and 142 (or 147 and 145), so
there's something going on there, one way or another. Also, I can think
of no other use for that 'corner notch' in the cab.

Of course, "blows them away" is a subjective thing. I always felt that
when I converted my Leslie From Hell into the LowBoy From Hell -- same
speakers, crossover, and amp -- I got arguably *more* bass, but it
wasn't the bass I wanted. I lost some of the lowest bass, traded off
for a bit of extra 100-200Hz. Personally, I hate overly warm bass; I
prefer a very deep, almost 'cold' bass that can be felt more than
heard. That requires a big cabinet, and probably some port tuning, too.

As for the 50C, if you've removed the 6x9s and *not* plugged up the
holes: yeah, you've got all kinds of bass leaks. It can even happen
with the speakers still in place, if the cones aren't really stiff. I
don't know what they did on the 50C, but my 251 had a pair of enclosures
to go around those 6x9s -- and two holes that pointed into the upper
rotor opening.. They weren't sealed very well, but the first thing I
did was to put weatherstripping around the edges of the little boxes.

Regards,

-BW

Bruce Wahler
Ashby Solutions.com^(TM)
bw@ashbysolutions.com
http://music.ashbysolutions.com
877.55.ASHBY (877.552.7429)

On 2/6/2013 9:56 AM, Dennis wrote:
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