A floor-type speaker system created by TB Livingstone and RH Rackham based on sketches left by Tannoy founder GR Fountain.
GRF stands for Guy R. Fountain.
As Tannoy's traditional dual concentric unit, it is equipped with the 38cm coaxial unit 3839M, which is the pedigree of classic monitors.
Dual concentric is a coaxial unit in which the woofer cone is a geometric extension of the horn tweeter in the center, and although it is a 2-way system, it has the feature of emitting sound from a single point like a single cone speaker. I am.
The cone of the woofer section uses a hard cone custom made by Kurt Muller of Germany. This cone is unique to Tannoy and is made by coating a thin cone paper with a special chemical and 8 ribs glued radially on the back side, and is named the Guard Acoustic Cone. This guard suppresses cone division vibration and improves transient characteristics and power handling characteristics.
In addition, the edges are made of a special polymer material called Tano Plus Surround that is molded into a unique shape.
Each voice coil is hand-wound and specially treated to withstand 240-degree high-pitched sounds.
The tweeter section consists of an inverted dome-shaped diaphragm made of lightweight hard aluminum alloy, which is integrally pressed up to the rolled edges, and a voice coil made of aluminum wire. This diaphragm is gradually formed into a dome using a 6-step pressing method, and is heated to remove internal distortion with each press. Moreover, an acoustically balanced cavity is provided on the opposite side of the diaphragm to improve transient characteristics and reduce distortion.
In addition, 19 throats are opened in the neck of the horn to correct the phase.
The crossover network can be adjusted in two ways from the front baffle: roll-off and energy.
Roll-off adjustment allows you to adjust high frequencies above 5kHz in 4 steps, and energy adjustment allows you to increase or decrease the entire tweeter level from 1kHz to 20kHz in 5 steps. The Level position of each adjustment knob is the normal position.
Carefully selected components are used in the network, including low-loss non-polar capacitors, and large-capacity, high-precision resistors and coils.
The enclosure is made of solid walnut and is designed as a bass reflex type with a volume of 220L.
In addition, cork material is pasted on the front baffle to prevent resonance.
The net grill is specially made from a blend of ivory and brown.
Furthermore, a locking method with a key is used to securely fix the Saran Net board and prevent resonance during high power.
The key is made of die-cast metal with a solid design that shines in gold.
The network plate on the front baffle has the wish ``Forever Fountain'' and is engraved with a map of England and R.H. Rackham's dedication ``The Fountain taught me the heart of sound.''
Specifications
| method | 2 way, 1 speaker, bass reflex system, floor type |
| Unit used | For all bands: 38cm coaxial cone type (3839M) |
| Play frequency band | 29Hz-20kHz, ±3dB |
| Output sound pressure level | 92dB/W/m(40Hz~20kHz) 113dB/120W/m(40Hz~20kHz) 119dB/500W/m(peak) |
| Allowable input | 120W continuous (50Hz to 1kHz) 500W peak (1kHz to 20kHz) |
| Nominal impedance | 8Ω (5.5Ω minimum) |
| Third harmonic distortion rate | 0.5% or less (90dB SPL, 40Hz to 20kHz) 2.0% or less (110dB SPL, 80Hz to 20kHz) 5.0% or less (113dB SPL, 80Hz to 20kHz) |
| crossover frequency | 1kHz, 12dB/octave |
| control network | 1kHz to 20kHz (±6dB/oct, 5 positions) 5kHz to 20kHz (+3dB to -6dB/oct, 4 positions) |
| Internal volume | 220L |
| External dimensions | Width 800x Height 1100x Depth 480mm (including legs) |
| weight | 62kg |
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