Sony SS 7330
A bookshelf speaker system using Sony's Ultra Linear Magnetic Path technology for reduced distortion
Overview
The Sony SS-7330 ULM33 is a 3-way bass reflex speaker system built for high-fidelity reproduction. It uses Sony's ULM (Ultra Linear Magnetic Path) magnetic circuit, which aims for low distortion by controlling the magnetic field precisely. The drivers are a 30 cm cone woofer, a 10 cm cone midrange and a 2.5 cm dome tweeter. They sit in a bookshelf-sized enclosure made from 20 mm hard particleboard. There are level controls for the middle and high frequencies, plus a switch that bypasses the internal crossover so the drivers can be run directly.
Specifications
| Model Rating Method | 3-Way, 3-Speaker, Bass reflex system, Bookshelf Type |
| Unit For low band | 30 cm cone type |
| Unit For Medium Range | 10 cm Cone Type |
| Unit For high-pass | 2.5 cm dome type |
| Playback frequency band | 40 Hz to 20000 Hz |
| Output sound pressure level | 88dB/W/m (New JIS) |
| Impedance | 6 Ω |
| Maximum allowable input | 100W (weighted pink noise) |
| Crossover frequency | 600 Hz, 3.5 kHz |
| External dimensions | Width 390 x Height 636 x Depth 310 mm |
| Weight | Approx. 22 kg |
Design
In the ULM magnetic circuit, the center pole has a notch and copper plating, which reduces nonlinear magnetic distortion. The woofer has a metal bobbin and a special alloy resin adhesive for more power handling. Its high-rigidity cone extends the piston vibration range and keeps internal loss low. The network uses large air-core coils to prevent distortion under high input. A dust cap with sound insulation suppresses abnormal noise. The decorative edge of the enclosure is shaped to reduce acoustic interference. Level controls for mid and high frequencies are provided. The switch removes the LC network for direct tri-amp driving of the drivers.
Market
The SS-7330 was listed for CAD $200.00 in September 2022, with no shipping because of its weight. It is noted as being very rare and desirable among collectors.
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