JBL UT-045Be (2002)
The JBL UT-045Be is a super tweeter system introduced in 2002 at a Japanese retail price of ¥500,000 for a set of two. It's a compression driver design that JBL says came directly from the Project K2 S9800 flagship. The idea was to take the top-tier studio monitor technology and put it in a standalone high-frequency unit for high-end home systems.
The engineering is unusual. The diaphragm is a 1-inch (2.5 cm) forged pure beryllium dome, which JBL claims plays in piston motion range up to beyond 50 kHz. It uses a neodymium ring magnet and sits on a biradial horn with 60° horizontal x 30° vertical directivity, in an aluminum die-cast housing. The body measures just 107 x 67 x 129 mm and weighs 970g. A tilt mechanism allows fine adjustment of the directional axis down to -2° vertically.
The unit ships with a separate external high-pass network (107 x 55 x 195 mm, 1 kg). It offers switchable crossover points at 16 kHz, 20 kHz, or 22 kHz with -18 dB/octave slopes, plus three attenuation steps (98, 100, or 102 dB/W/m output). JBL used low-loss air-core coils and high-quality capacitors in the network. It also applied its "charge-coupled linear definition" method, which applies DC bias to eliminate nonlinear capacitor distortion. A large binding post terminal handles connections.
Known specs:
- 1-way, 1-speaker super tweeter system
- Horn-type 2.5 cm beryllium compression driver
- Frequency characteristic: Fc to 55 kHz
- Impedance: 4 Ω
- Allowable input: 20W
- Crossover: 16/20/22 kHz, -18 dB/oct (switchable)
- Output SPL: 98/100/102 dB/W/m (switchable)
- Body: 107W x 67H x 129D mm, 970g
- Network: 107W x 55H x 195D mm, 1 kg
- Includes spike feet, spike receivers, and hex driver for adjustments
Documentation on the UT-045Be is thin. No period reviews from the major audio magazines have surfaced, and JBL's own catalog material is scarce. What's clear is that it was a serious, esoteric component aimed at the upper end of the Japanese domestic market, sold as a matched pair with external networks. HiFi-Do's current buyback price of ¥130,000 suggests it retains meaningful collector interest, though the record doesn't show how long production ran or how many pairs were made. The 5.2 mm magnet diameter listed in the sources seems exceptionally small for a driver of this class and may be a typographical error in the original documentation.
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