The ET-703a is one of the world‘s most efficient and broadband reproduction loudspeakers for super high frequencies. TAD has fine-tuned the ET-703, known as a true rear compression type horn tweeter with this triple-slit fading plug. The 35mm beryllium diaphragm is extremely lightweight at only 0.07gr, and in synergy with the aluminum edge-wound voice coil insulated with an anodized aluminum coating film, combines outstanding response with a wide frequency bandwidth and high input power. The phasing plug is triple-slit type with slit spacing of approx. 5 mm, enabling reproduction up to 45 kHz. The magnetic circuit is provided by samarium-cobalt magnet that can ensure stable output even in high-temperature operation, and the magnetic flux density can reach 2 Tesla. The ET-703a will further revolutionize the world of digital sound monitoring.
Diaphragm with integrated surround made of pure beryllium
Using our unique vacuum evaporation technique, we have succeeded in integrating the surround and diaphragm with beryllium.
By designing the resonance frequency of the surround higher than 50 kHz, the negative effects on the audible frequency band are eliminated. Furthermore, despite the large 35 mm diaphragm, the diaphragm is ultra-lightweight at 0.07 g, and the high resonance frequency is as high as 45 kHz. As a result, a wider reproduction bandwidth, excellent transient characteristics, and outstanding resolution are achieved.
Rear compression type horn tweeter
A rear compression type horn tweeter is produced by hollowing out the inside of the pole yoke to create a sound path and mounting the diaphragm from the rear. This method ensures ideal phase equalization up to the ultra-high frequency areas. The effect of surround vibration is minimized, resulting in a highly transparent sound and smooth extension of high-frequency.
Triple-slit ultra-precise phasing plug
A triple-slit phasing plug, which was precisely designed using a computer based on acoustic theory, is installed. The good equalization characteristics provide smooth frequency response characteristics up to above 30 kHz, reproducing sensitive ultrahigh frequencies with high resolution.
The surfaces of the phasing plugs are finished by high-precision machining with a tolerance of 20 μm to ensure high reliability.
Voice coil of pure aluminum edge-wound wire
A voice coil of edge-wound wire made of anodized pure aluminum is used. The conductor occupancy in the magnetic circuit is increased to the utmost limit to achieve high efficiency. In addition, heat-resistant materials are used for the voice coil bobbin and adhesives to ensure stability to withstand large input power of 30 W.
Rare-earth Samarium-cobalt magnet magnetic circuit
Rare earth samarium-cobalt magnets with high magnetic energy are built into the limited volume of the super tweeter. Its powerful magnetic characteristics, combined with the electromagnetic soft iron showing extra low carbon and low impurity used for the pole yoke and plate, constitute an ultra-strong magnetic circuit with a magnetic flux density of 2 Tesla and a total flux of 40x10-4 Wb.
ET-703a Specification
- Rated impedance: 8 ohms
- Frequency Response: 5,000 to 45,000 Hz
- Voice coil diameter: 35 mm (1 3/8 in.)
- Equalization system: Triple-slit rear compression type
- Mounting Information:
- Mounting on the baffle
- Baffle opening diameter: 81 mm (3 3/16 in.)
- Mounting pitch: 98 mm (3 55/64 in.) (for 4-hex socket head cap screws)
- On to the enclosure: 25 mm (63/64 in.) (for 2-wood screws)
- Rated input power: 15 W for crossover frequency at 5 kHz -12 dB/oct
- Maximum input power: 30 W for crossover frequency at 5 kHz -12 dB/oct
- Sound pressure level: 107 dB at 1 W, 1 m (anechoic conditions)
- Crossover frequency: 5000 Hz or higher (-12 dB/oct or higher)
- Total magnetic flux: 4.0 x 10-4 Wb
- Magnetic flux density: 2.0 Tesla
- External dimension: φ80 mm x 74 mm (Depth)
- (φ3 5/32 in.×2 29/32 in. (Depth))
- Weight: 1.1 kg (2 lb 7 oz)
- Accessories: Mounting flange (1), Mounting packing (1),
- Hex socket head cap screws (4), Washer (4),
- Cross-recessed head wood screw (2),
- Hex wrench (1), Instruction manual (1)
