Sony FW-90

Part of those added x-rare elements revolving around the ESPRIT series, like the TAC-90 and TAC-91 enclosures or the über-rare HA-T1 phono MC head-amp.

Sony advertised for the FW-90 as much as it did for the SE-P900 parametric EQ - quite a lot for an "accessory".
But both wound up being just as rare as the other.


FW-90 stands for Floating Magnet Sound Base.

Two (fairly) strong magnets held together make vibrations go away because only air stands between them.
No springs, no ultra-elliptical shape with sinusoidal cancellation nodes added, no super-duper material carved from pure Delirion with gold-plated Mirifica.
No strings and no leafs either. Just air.
Levitation really. It does wonders.

The result is a sharper reduction of parasitic resonance levels, mainly between 100Hz and 1Khz.


Each FW-90 Sound Base can support between 3,5kg and 7kg : lighter than 3,5kg and the top magnet remains hooked to its stopper, heavier than 7kg and it is crushed onto its repulsive sibling.

Sound Bases should remain level and generally put under a intermediary board on which the component will be placed.

If no board is available (or desired), the Sound Bases can be put directly under the component, under the original feet of the latter.

The flux leakage of the magnets remains minimal but wristwatches and recorded tapes should nevertheless remain distant from the FW-90.


If using a PS-X9, six FW-90 should be used : 35kg divided by 6 makes an individual load of 5,8kg.
Optimum, even if a little expensive.

If using a pair of TA-N900 monoblocks, eight FW-90 should be used with two heavy objects of 10kg each added on each TA-N900 for an individual load of 5kg.
Mmmm - just as optimal but getting quite expensive.

If using a pair of APM-6, sixteen FW-90 should be used for an individual load of 6kg - heaven.
But, ahhh, ohhh, this is really getting to be too expensive !

Probably why the FW-90 didn't sell better.

But it does wonders.