SYSTEM DESCRIPTION AND PHILOSOPHY

A loudspeaker design naturally divides into various parts: cabinet, drive unit(s) and crossover. The design of these parts cannot take place in isolation as they are all interdependent.

Drive unit.

The drive unit used in the System 800 monitors is part of the latest generation of Dual Concentric units designed by Tannoy. Among many others features, this range of drivers incorporate a dual magnet assembly, ‘tulip’ HF waveguide and injection moulded polypropylene LF cone.

The design of the HF waveguide has been arrived at by making extensive use of CAD (computer aided design). It matches the acoustic source impedance at the HF diaphragm into the acoustic environment, shaping the wavefront as it travels down from the diaphragm ensuring equal path lengths to achieve a spherical wavefront. Wavefront shaping begins at the diaphragm surface and, because the compression ratio can be kept relatively low with this design, the distortions due to air non- linearities are minimised. A hyperbolic flare has been chosen for optimum low frequency performance at the crossover point.

The HF diaphragm is made from aluminium and magnesium alloy, with optimised shape and thickness providing rigid piston behaviour up to 25 kHz. The diaphragm assembly is suspended by a precision moulded, inert nitrile rubber surround. Its very narrow roll eliminates resonances below 25 kHz and provides a very stable and consistent mounting. The roll form ensures high excursions can take place if necessary yet provides a fatigue-indestructible assembly.

The HF voice coil assembly incorporates a high temperature copper wire chemically bonded onto a kapton former fitting onto the outside of the HF diaphragm skirt. The thermal power handling of the voice coil is greatly increased thanks to its ferrofluid filled magnetic gap.

Physically, the whole HF assembly self centre mounts onto the back of the low frequency assembly using three screws carrying with it the self-centring HF diaphragm. Production and field service is therefore virtually foolproof and extremely consistent.

The LF unit uses a CNC precision injection moulded polypropylene cone, terminated by a nitrile rubber, high-compliance surround. The characteristic cone termination impedance is matched by the surround material independently of the required suspension compliance. The unit system compliance is provided by the rear suspension where the best degree of mechanical control can be provided.

The shape of the LF cone has been calculated to match the HF hyperbolic waveguide ensuring the wavefront remains spherical and perpendicular to the cone surface throughout the propagation.

Purpose-designed trim rings are used to blend the HF wavefront into the cabinet. This feature has been shown in our research to be the biggest single factor in providing smooth HF radiation in Dual Concentrics.

The heart of the LF unit is the motor system comprising the magnet and voice coil. The choice of magnet operating point parameters, air gap flux strength, voice coil details (number of turns, resistance, winding length, diameter etc.), moving mass, dynamic compliance and drive unit radiating area presents a very complex mathematical problem where the solutions can take many different forms. Reaching the correct answers is much easier if computers can be called on to assist with solving the equations, as Tannoy do for its drivers.

Cabinet.

Aside the drive units, cabinet design plays a major role in the acoustic performance of a speaker system. Among the problems which can contribute to the degradation of

Page 3 Page 5
Page 4
Image 4
Tannoy 800 user manual System Description and Philosophy, Drive unit, Cabinet
Page 3 Page 5

800 specifications

The Tannoy 800, a remarkable loudspeaker, is part of Tannoy's prestigious line of products known for their high-quality audio reproduction. As a staple in professional audio environments, the Tannoy 800 embodies the brand's commitment to excellence, providing an exceptional listening experience for both audiophiles and industry professionals.

One of the standout features of the Tannoy 800 is its Dual Concentric driver design. This innovative technology integrates the high-frequency and low-frequency drivers into a single point source. This design minimizes phase issues and ensures coherent sound dispersion across a wide frequency range. As a result, listeners enjoy accurate audio reproduction, making the Tannoy 800 ideal for critical listening situations.

The Tannoy 800 boasts impressive frequency response, typically ranging from 50 Hz to 20 kHz. This extensive range allows for a rich bass presence while maintaining clear highs, ensuring that every detail of the audio is reproduced faithfully. The speaker's sensitivity, a crucial measurement in determining its efficiency, sits around 90 dB, making it suitable for both home and professional studio applications.

Another notable characteristic of the Tannoy 800 is its robust build quality. The cabinets are constructed from high-density MDF, which reduces resonance and enhances sound clarity. The design not only contributes to the speaker's durability but also minimizes coloration, delivering a more natural and pure sound.

The Tannoy 800 also integrates advanced acoustic engineering techniques such as a finely tuned ported enclosure. This feature enables the speaker to produce deep bass frequencies while preventing distortion. The rear-firing port design optimizes airflow, allowing for improved efficiency without sacrificing sound quality.

Connectivity options are abundant, ensuring versatility in various setups. The Tannoy 800 is equipped with bi-wire and bi-amp capabilities, giving users the flexibility to customize their audio experience further. Additionally, the speaker's compatibility with various amplification systems makes it a valuable choice for both studio and home sound systems.

In summary, the Tannoy 800 encapsulates the essence of high-fidelity audio through its Dual Concentric technology, extensive frequency range, robust build quality, and versatile connectivity options. With such features, it stands as a top choice for anyone serious about audio integrity, whether in professional studios or home listening environments. The Tannoy 800 is a testament to the brand’s dedication to quality and innovation in sound reproduction.
Top Page Image Contents