Linoleum is a natural usually 2.5mm thick sheet membrane material. It may be said to be responsible for part of the bass clear sound of modern recorded music history. Why?
Initially acoustic spaces had wood paneling near walls for bass (reverberation) absorption. Disadvantage is wood reasonamce coloration by such re reflected energy.
Linoleum is possibly the first elastomer material used in place of wood.
Firstly used by C. W. Goyder at All India Radio in Delhi, then BBC decided to use as an alternative betumin roofing felt absorbers for its elastomer properties [Gilford]. Possibly so EMI or other recording studios made use of such elastomer materials [euroelectron]. These elastomer hysterisis loss materials when sound falls on them vibrate. By vibrating they dissipate energy to heat.
They will not significantly heat the room but they will remove most of the bass mode reverberation acoustic mudd or bass heavy sound ugliness.
So why linoleum for speakers instead of wood, plastic etc?
Wood has its important place for production. For example on making a guitar, a piano, a woodwind. But at reproduction we desire non coloration. Linoleum does not have a sound. It just absorbs. And if it re radiates the sound would be much less colored.
It is thin. So most of the acoustic energy is not trapped to multiple mirror reflection vibration inside speaker enclosures as would be using thick sound insulating materials such as wood.
It is very beautiful. It comes in many extraordinary colors made of natural pigments [Tarkett].
It is expensive. So virtually excluding cheap pirate copies.
It is cut very easily. Using ordinary common sense adequate safety measures.
It is bent very easily and its strength remains as the juta reinforcement backing retains the strength.
It cannot withstand large mass at large areas (unless used as a baffle). This limits speaker dimensions to relatibely small with the advantage of accuracy, good imaging, soundstage, less diffraction effects, nearly point source radiation, use of one only fullrange speaker etc.
The sides of enclosures will vibrate at bass frequencies in a damped way making the bass deeper than their size would suggest.
When used on tetrahedron (Triagular pyramid) Pleiades speakers for example, the sides radiate a clear and amazing quality deep bass which can be reinforced if desired by approaching the speaker near room boundaries. Near the corner for example the ingenious Klipschorn effect can be used by making the walls parts of the bass horn.
It is a natural material made from natural recyclable ingredients [Tarkett], so it is friendly to the environment.
It has a desirable non synthetic odor.
It is enjoyable to hold and its vibration absorbing properties are felt even by touch.
The first ever made loudspeaker using only linoleum is possibly the Pleiades linoleum Auratone 5C type monitoring cube speaker. Date time unique identification number is 19041715. Ie 17th of April 2019 at 3:00pm.
As with any analytical speaker of exceptional transient response immediately reveiling any sound problem, no feedback, few component class A (electrons flowing all the time) amplifiers must be used such as the Pleiades one electron tube or one transistor amplifiers. (Taking all safety precautions, at your risk).
The joy is in playing.
References:
Acoustics for radio and television studios - Christopher Gilford - IEE monograph series 11 - 1972 - page 158 - sound absorbers - membrane and panel absorbers
Other euroelectron posts on BBC, EMI acoustics
Tarkett linoleum catalogues and data
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