ขาย Elac 4Pi PLUS2

ELAC 4Pi Plus.2
super-tweeters
René van Es
Being bitten by the super-tweeter bug a few months ago I took the opportunity to try a pair of ELAC 4Pi Plus.2 super-tweeters at home. This is an omnidirectional ribbon tweeter that has been on the market for a very long time and has been incorporated into some of ELAC’s best loudspeakers in the past, it has now partly been replaced with the JET ribbon tweeter. The 4Pi Plus.2 however, remains available to enhance the performance of any loudspeaker.

The 4Pi Plus.2 is omnidirectional. The ribbon behind the mesh grille is only 0.006 mm thick and moves in a high power magnetic field produced by neodymium magnets above and below. Since this ribbon is round the sound projects to all sides through the mesh grille. It has a very low impedance, too low for any amplifier and therefor the 4Pi incorporates a transformer to give it a six Ohm nominal impedance that drops to three and a half Ohms at 10kHz. The 4Pi is not a small add-on, it measures 150mm wide and 250mm deep. Behind the tweeter’s ‘mushroom’ two rotary switches let you choose the efficiency and the crossover frequency. The 4Pi will match any speaker with an efficiency between 84 and 92dB with -4,-2, 0, +2 and +4dB settings. The crossover frequencies are 10, 12 and 15kHz and the claimed frequency range is 10 to 50kHz. The cabinet and knobs do shine: high gloss black, chrome and aluminium looks pretty impressive even on top of a pair of floor standing speakers like my PMC fact.12. Connections are made with WBT binding posts. Strangely my wife found them far more attractive than the small Townshend super-tweeters in normal use.

SPECIFICATIONS:
Speaker type : Add-on high-frequency driver
Tweeter : omnidirectional ribbon
Crossover frequency : 10,000 / 12,000 / 15,000 Hz adjustable
Frequency response : 10,000 to 50,000 Hz
Sensitivity : 84 to 92 dB at 2.83 v/1m
Recommended amplifier power : 20 to 400 wpc
Nominal/peak power handling : 400 / 600 wpc
Nominal impedance : 6 Ω; minimum 3.5 Ω @ 10,000 Hz
Binding posts : 5-way metal
Magnetic shielding : No
Cabinet finish : High gloss black
Height : 5.6 in / 143 mm
Width : 5.9 in / 150 mm
Depth : 9.8 in / 250 mm
Net weight (each) : 8.8 lb / 4.0 kg