here is the compressor
http://www.aircomps.co.uk/product/ba...nt-compressor/

Bloodyhell, i imagine the silent operation was a major requirement then? and
3.5 cfm is really **** all, it' the minimum requirment of most air small
tools, my direct drive noisy as hell cheapo compressor delivers about 7 cfm,

a standard belt driven twin stage compressor head, induction motor and large
tank that could do those pressures and volume would have cost half as much,
but be noisier.... tho able to run almost all day,

Those 'silent' compressors are basically large fridge compressor units, sure
they are almost silent in operation, but they are crap at shedding heat due
to the sealed insulating shroud (green bits)
in a fridge it's moving the refrigerant around, sure it's compressing it a
bit, but it is and open loop so to speak,

in an air compressor, the motors are pushing against a closed tank, thus the
pressure is increasing, and the heat rises as it gets harder and harder to
push the air into the tank,