This was realized almost by accident today.
At your risk.
At Pleiades Lab usually elastomer membrane absorbers behing painting canvas using canvas frames are hanged from ceiling and spaced from walls for bass reverberation absorption (see older posts).
Picture Hanging Systems UK materials are used like on museums for picture exhibition.
Recently a Zeiss Ikon baffle speaker had been hanged.
And today a nearby Heithkit electron tube amplifier on the floor had been connected to it. See today's posts.
Bass is very deep, jaw dropping deep.
Subjectively it sounds like going down almost flat to 40Hz.
Yet the baffle size is only 20in by 20in and the high class drive unit is only 7in, (6in paper membrane).
This may be explained by:
The gentle (only 6dB per octave) bass drop of baffle speakers compared to 12dB per octave on closed infinite baffle ones and 24dB per octave of bass reflex or vented enclosures.
Further listening and touching tests revealed that the wooden baffle vibrates at bass frequencies. A large area vibrating creates acoustic impedance match. Bass needs a lot of air to be moved and a large area does this.
Wood panel vibrates as the mechanical wave inside it travels from drive unit to edges and is reflected back due to impedance mismatch at the free boundaries of wood. Just like drums or even better cymbals. Or water waves reflected at the edges of a swimming pool.
The baffle wood panel becomes like a small piano soundboard.
The 7in speaker somewhat becomes a 20in x 20in speaker which is a huge speaker.
How would linoleum baffle speakers sound carefully hanged from ceiling?
Would they dissipate resonances by elastomer absorption?
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