INFINITY IRS
* Production to order for 3 months or more
¥ 12,000,000 (1 system, about 1980)
¥ 10,000,000 (1 system, circa 1981)
Commentary
A speaker system developed by combining Infiniti's technologies.
The product name IRS stands for Infinity Reference Standard.
The IRS consists of four cabinets and is a large system with a height of 2.29m and a total weight of 544.8 kg.
The mid - and high-range enclosure contains 24 EMIT and 12 bi-directional EMIMs on the front and 12 on the back, while the low-range enclosure contains six 30 cm cone woofers.
A 30 cm cone type woofer is installed in the low range.
This unit uses a unique dual voice coil system to solve the problem of low resonance frequency (fo). This structure uses two voice coils with different impedance. In principle, when the first voice coil approaches fo, the second voice coil gradually takes over and flattens the frequency characteristics.
In addition, polypropylene is used for the diaphragm.
EMIM (Electromagnetic Induction Mid Range) is mounted in the middle range.
This unit is bi-directional with an ultra-lightweight plastic diaphragm sandwiched between strong magnetic materials such as samarium-cobalt.
EMIT (Electromagnetic Induction Tweeter) is installed in the high range.
Similar to the EMIM, it is a full-surface drive type made of samarium-cobalt lightweight plastic diaphragm sandwiched by samarium-cobalt, and realizes ultra-high frequency reproduction up to 32 kHz.
Model Rating
| Method | 3-way, 54 speaker floor type |
| Configuration | Consists of four units (includes 1.5 kW servo amplifier for two woofer units) |
| Units Used | For low band : 30.0 cm cone type x6 (driven by servo amplifier with MFB) For Medium Range : 12 EMIM Type For High Range : EMIT Type x36 (24 Front, 12 Back) |
| Woofer amplifier | Two monaural amplifiers Output : 1.5 kW Woofer servo system using US military standard エクセロロメータ Approximately 20 dB feedback is possible |
| Frequency characteristic | 15 Hz to 40 kHz ± 2 dB |
| Crossover frequency | Woofer / Midrange : 70 Hz (standard setting) * Variable from 60 hz to 120 hz with attached control amplifier Mid-range / Tweeter : 5 kHz (tweeter level control) |
| Recommended amplifier | Mid-range / Tweeter : Amp up to 500W/ch and up to 100W/ch |
| Control amplifier | Contour control Bus variable low pass filter Low-pass variable damping Woofer level control Input impedance control for mid-range / tweeter amplifier Woofer phase switch Servo bus ON/OFF circuit |
| External dimensions | Woofer unit : 457 mm wide x 2290 mm high x 457 mm deep Mid-range / Tweeter unit : 100 mm wide x 2290 mm high x 250 mm deep (Base Part : Width 100x Depth 450 mm) |
| Weight | 544.8 kg (system weight) |