Fitzmaurice Snail III as home speaker

[[email protected]]

Has Arny read Bill Fitzmaurice's book, 'Loudspeakers for Musicians',
and seen his Snail III design? Perhaps he would comment on the issues
with phase from the wildly differing distance from the woofer and
midrange/tweeter (which are in D'Appolito configuration) if he has.
Of course, then again, perhaps he wouldn't.

[Michael McKelvy]

> wrote in message
oups.com...
> Has Arny read Bill Fitzmaurice's book, 'Loudspeakers for Musicians',
> and seen his Snail III design? Perhaps he would comment on the issues
> with phase from the wildly differing distance from the woofer and
> midrange/tweeter (which are in D'Appolito configuration) if he has.
> Of course, then again, perhaps he wouldn't.
>

Why not talk directly to Fitzmaurice? He is a regular contributor at
www.diyaudio.com

[Arny Krueger]

wrote:

> Has Arny read Bill Fitzmaurice's book, 'Loudspeakers for Musicians',

Nope.

> and seen his Snail III design?

A little research shows that this design was also covered in Audio
Express.

> Perhaps he would comment on the issues
> with phase from the wildly differing distance from the woofer and
> midrange/tweeter (which are in D'Appolito configuration)

If you filled me in with some relevant info, such as crossover points
and the actual difference in path distance, I could comment about the
general case.

For the record, I'm not a fan of low frequency horns on the grounds of
simple domestic practicality. OTOH, I have had positive experiences
with mid and high frequency waveguides (the proper name for horns).

To give you more insight into my opinions about speakers, I'm currently
mentally playing with a design composed of B&C drivers. Of course there
would be a separate subwoofer perhaps built out of large JL Audio W7
series drivers.

The woofer might be a B&C 18", not chosen primarily for air-moving
capability, but rather for directivity control. I'm thinking of
covering the 80 to 270 Hz range with it. Then an 8" B&C driver would
cover from 270 to 800 Hz, again with directivty control in mind. A
constant directivity waveguide-based midrange-tweeter would cover
through at least 8-10 KHz. If I couldn't eq enough high treble into
that part of the system, a small waveguide-based supertweeter would
finish out the audible range. Due to the extreme efficiency of the
drivers, no more than 200 wpc would be required to cleanly handle
120dB+ SPLs. The active crossover would be Berhingers' new digital
unit.

The drivers would be positioned in a row with their lower edges just
above the floor line to minimize the effcts of the usually-ubiquitous
floor bounce. Total enclosure size would be about 6 cubic feet.

[[email protected]]

Fitzmaurice probably published it first at Speaker Builder or AX (its
continuation publication) as they are the publisher of this book.

[ScottW]

Arny Krueger wrote:
> wrote:
>
> > Has Arny read Bill Fitzmaurice's book, 'Loudspeakers for
Musicians',
>
> Nope.
>
> > and seen his Snail III design?
>
> A little research shows that this design was also covered in Audio
> Express.
>
> > Perhaps he would comment on the issues
> > with phase from the wildly differing distance from the woofer and
> > midrange/tweeter (which are in D'Appolito configuration)
>
> If you filled me in with some relevant info, such as crossover points
> and the actual difference in path distance, I could comment about the
> general case.
>
> For the record, I'm not a fan of low frequency horns on the grounds
of
> simple domestic practicality. OTOH, I have had positive experiences
> with mid and high frequency waveguides (the proper name for horns).
>
> To give you more insight into my opinions about speakers, I'm
currently
> mentally playing with a design composed of B&C drivers. Of course
there
> would be a separate subwoofer perhaps built out of large JL Audio W7
> series drivers.
>
> The woofer might be a B&C 18", not chosen primarily for air-moving
> capability, but rather for directivity control. I'm thinking of
> covering the 80 to 270 Hz range with it. Then an 8" B&C driver would
> cover from 270 to 800 Hz, again with directivty control in mind. A
> constant directivity waveguide-based midrange-tweeter would cover
> through at least 8-10 KHz. If I couldn't eq enough high treble into
> that part of the system, a small waveguide-based supertweeter would
> finish out the audible range. Due to the extreme efficiency of the
> drivers, no more than 200 wpc would be required to cleanly handle
> 120dB+ SPLs. The active crossover would be Berhingers' new digital
> unit.

The DCX2496? SPDIF or analog in? How were you planning to handle
volume control? On analog outs before PA or in the amps?

This thing is pretty amazing for the price. If I was planning to tinker
with speaker building... I'd have one just to allow easy crossover
experimentation.

>
> The drivers would be positioned in a row with their lower edges just
> above the floor line to minimize the effcts of the usually-ubiquitous
> floor bounce. Total enclosure size would be about 6 cubic feet.

The delays allow all kinds of different/unusual driver configurations
but I don't think Howard would approve of the small sweet spot such a
configuration would create.

ScottW

[Arny Krueger]

ScottW wrote:
> Arny Krueger wrote:

> > To give you more insight into my opinions about speakers, I'm
> > currently mentally playing with a design composed of B&C drivers.
Of > > course there would be a separate subwoofer perhaps built out of

> > large JL Audio W7 series drivers.

> > The woofer might be a B&C 18", not chosen primarily for air-moving
> > capability, but rather for directivity control. I'm thinking of
> > covering the 80 to 270 Hz range with it. Then an 8" B&C driver
would
> > cover from 270 to 800 Hz, again with directivty control in mind. A
> > constant directivity waveguide-based midrange-tweeter would cover
> > through at least 8-10 KHz. If I couldn't eq enough high treble into
> > that part of the system, a small waveguide-based supertweeter would
> > finish out the audible range. Due to the extreme efficiency of the
> > drivers, no more than 200 wpc would be required to cleanly handle
> > 120dB+ SPLs. The active crossover would be Berhingers' new digital
> > unit.

> The DCX2496? SPDIF or analog in?

Probably analog, at least initially. The system controller I'd use it
with has a good digital volume control, but it does only have analog
outputs. I've long considered the possibility of buffering out the
digital data stream inputs to its DACs.

> How were you planning to handle volume control? On analog outs
before > PA or in the amps?

Analog. I've done enough listening tests of cascaded ADCs and DACs to
not have misapprehensions about multiple domain changes.

> This thing is pretty amazing for the price. If I was planning to
tinker
> with speaker building... I'd have one just to allow easy crossover
> experimentation.

I have a friend who sells one in a portable box with appropriate power
supplies and signal sources for use as a design tool.

> > The drivers would be positioned in a row with their lower edges
just
> > above the floor line to minimize the effcts of the
usually-ubiquitous
> > floor bounce. Total enclosure size would be about 6 cubic feet.

> The delays allow all kinds of different/unusual driver configurations
> but I don't think Howard would approve of the small sweet spot such a
> configuration would create.

Howard isn't my technical guide. IME a well-defined sweet spot can be
sweeter for the very reasons that it is small.

[Blind Joni]

>The woofer might be a B&C 18", not chosen primarily for air-moving
>capability, but rather for directivity control. I'm thinking of
>covering the 80 to 270 Hz range with it

Explain to me how the choice of a raw speaker has an effect on directivity in
this frequency range.


John A. Chiara
SOS Recording Studio
Live Sound Inc.
Albany, NY
www.sosrecording.net
518-449-1637

[Arny Krueger]

"Blind Joni" > wrote in message


>> The woofer might be a B&C 18", not chosen primarily for air-moving
>> capability, but rather for directivity control. I'm thinking of
>> covering the 80 to 270 Hz range with it
>
> Explain to me how the choice of a raw speaker has an effect on
> directivity in this frequency range.

I'm looking into applications of cardioid loudspeaker design principles to
provide that feature.

[Michael McKelvy]

> wrote in message
oups.com...
> Has Arny read Bill Fitzmaurice's book, 'Loudspeakers for Musicians',
> and seen his Snail III design? Perhaps he would comment on the issues
> with phase from the wildly differing distance from the woofer and
> midrange/tweeter (which are in D'Appolito configuration) if he has.
> Of course, then again, perhaps he wouldn't.
>
Is it safe to assume you have all the info you need on the Snail III?

If you need any additional info I have the article from Speaker Builder
Vol.19 Number 4 July 1998.