Sansui SP-20000

Sansui is not at all remembered for its loudspeakers - they made too many firing squads such as the SP-3005 and quite a few others. Kenwood suffers the same fate with its KL-7090 or KL-777D while its Model Seven and LS-1900 remain completely overlooked.

However, Sansui occasionally spent a lot time and money producing high-end loudspeakers, often with a strong JBL flavor. The big SP-G300 series was a direct attempt at competing with JBL on the japanese market - even though Sansui was the actual JBL distributor there ! Sansui even made... an SP-LE8T :)
I believe the SP-20000 to have been export-only, custom-developed for the US market.


The two horns in the SP-20000 use a patented construction system called Direct-Drive Ring Diaphragm, where the voice coil is the diaphragm and vice-versa. With a much lighter moving mass and perfectly symmetrical shape, a direct formation of the sound waves is allowed.
The result is improved phase response, no time delay, no propagation loss of energy and improved transient response. The very thin 4µ flat ribbon wire completely immersed in the magnetic field allows perfectly uniform pulsations.

Exponential horns made of diecast aluminium are mounted on the DDRD radiators. Both drivers show a large predominance of 2nd harmonics.

One 25,5cm free-surround woofer is next at hand(s) : the cone is hand-made from of specially-developed Kraft pulp suspended in a separate urethane ring. The long-throw voice coil is wound edge-wise ; corrugations are present to avoid cone breakup and resonances ; the frame holding the oversized saturable magnet is made of diecast aluminium.

Next at hands is the drone cone, or passive radiator : no voice coil, no electrical impulses, just a response to the radiations of the active woofer to reiforce low-frequency sounds solidly and realistically.


The crossover is composed of distortion-free air-core coils and metallized film capacitors ; an impedance correction circuit keeps distortion at all frequencies to a minimum. In the tweeter section, a polypropylene cap is combined with a bifilar coil so high frequency sound are never attenuated.
Five-step 2dB level controls are provided for the high and mid drivers.

The SP-20000 is sold in mirror-matched pairs and matched speaker stands made of aluminium tubing are delivered along ; the latter allow placement of the loudspeakers flat at 90° or with a slight backward angle.

All this seems impressive, doesn't it ?