SANSUI SP-XII
¥ 44,800 (1 unit, around 1972)
Commentary
This is a 3-way speaker system that uses DL cone woofer and emphasizes not only measurement but also listening feeling in the listening room.
A 25.5 cm cone type unit is used for the low range.
The cone paper uses DL cone, which is pulp cone coated with a special coating agent, to expand the piston motion band and improve S/N.
The voice coil is composed of four layers of 0.27 mm copper wire in series to increase the magnetic flux density and improve efficiency.
In addition, low Q-up roll edge with damping agent applied on both sides is used to lower fo.
3.5 cm soft dome type unit is adopted for the middle area.
The diaphragm is made of pure hemp and applied with damping agent, and inside the diaphragm is made of two layers of glass wool of micron fiber to give constant tension to the diaphragm.
As a result, the S/N ratio is improved by controlling the deformation vibration that appears as distortion and reducing the distortion.
The voice coil uses a 0.15 mm diameter C. C. A. W. that is lightweight and highly conductive, and the magnetic circuit uses a 11,000 Gauss magnet.
The frame is made of 4.5 mm thick die-cast aluminum to prevent deterioration of sound quality due to distortion of the frame, influence of resonance and magnetic flux leakage when the unit is mounted.
A 1.9 mm dome type unit is adopted for the high range.
The diaphragm is made of special fibers coated with damping agent and has a dome-shaped structure with a large protruding shape. This increases the diaphragm strength, controls split vibration and unnecessary deformation motion, and improves directional characteristics.
In addition, transient characteristics are improved by a C. C. A. W. voice coil using a 0.15 mm diameter copper-coated aluminum wire and a magnetic circuit with a magnetic flux density of 12,000 Gauss.
The frame is made of highly accurate 4.5 mm thick die-cast aluminum.
The network uses a laminated core with high magnetic flux density for low and middle regions, high dynamic margin, and no magnetic distortion even at high input power. This reduces distortion.
In addition, an air-core coil is adopted for the low cut of the tweeter to eliminate non-linear distortion caused by Oire force and improve linearity.
The enclosure is a closed type, and the material of the board and reinforcement material are carefully examined.
In addition, by adding a large amount of sound absorbing material, it can reproduce a deep low sound with good articulation.
In addition, special polyurethane is attached to the front baffle plate to improve phase characteristics and directional characteristics.
Model Rating
| Method | 3-Way, 3-Speaker, Airtight Type, Bookshelf Type |
| Unit | For low band : 25.5 cm cone type For Middle Area : 3.5 cm Dome Type For high-pass : 1.9 cm dome type |
| Frequency band | 40 Hz to 20000 Hz |
| Maximum allowable input | 55W |
| Impedance | 8 Ω |
| Output sound pressure level | 90dB/W/m |
| Crossover frequency | 1500 Hz, 10000 Hz |
| Network | High Cut (woofer) : 6dB/oct. Low Cut (Squaker) : 18dB/oct. Low Cut (Tweeter) : 18dB/oct. |
| Tweeter level | Middle and High Frequency : Volume type continuously variable (3 click point) |
| External dimensions | Width 346x Height 598x Depth 300 mm |
| Weight | 17.7kg |