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Wild_Bill Wild_Bill is offline
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Default Crate 4x12 Speaker Cabinet Partition for Stereo Use Model BV412SB

Thanks, I appreciate the informtion.
I had read that Crate specifically chose birch plywood for the cabinet due
to it's particular resonance characteristics, but I admit that a tuned
cabinet is way beyond what I know about acoustics or enclosures.


"spamtrap1888" wrote in message
On Nov 2, 1:58 pm, "Wild_Bill" wrote:
Would anyone know of a good reason to not install a partition between the
left and right pairs, when using the cabinet for a stereo input?

As it is now, there is just open space inside the cabinet.

All four speakers are identical (16 ohm) and there is a switch at the rear
to select mono (4 or 16 ohm) or stereo (2x8 ohm).

There aren't any baffles, ports or stuffing in the box, just bare inside..
and I was contemplating installing a wood or wood/foam separator.

From fundamentals: A loudspeaker in a box is a spring-mass-damper
situation. The mass is the mass of the diaphragms, voice coils, and
part of the surround and spider. The spring is the air in the
enclosure, which provides a restoring force to the diaphragms. This
gives a certain fundamental resonance, which is the low frequency
corner that the speaker can reproduce.

Now, if you put a partition in the middle, you halve the moving mass,
but you also halve the air volume. Intuitively the fundamental
resonance should not change, because the two factors cancel out. I
would verify this by finding the resonance with and without the
partition using an oscillator, AC voltmenter, and resistor.