Research & Development
Peter Comeau, head of acoustic design at IAG Group (home to iconic hi-fi brands including Wharfedale, Audiolab and Mission) has over 30 years experience in the hi-fi industry. Peter's efforts and experience within the industry means Quad's original approach to loudspeaker design and creating an authentic experience is achieved - yet with a strong focus on researching new technologies, materials and concepts to enjoy hi-fi and home cinema.
You can read a further insight into the science and art of building a speaker with Peter Comeau's What Hi-Fi Interview here plus a What Hi-Fi interview in the video below:
-Peter Comeau, What Hi-Fi ? Sound & Vision
-Pictured: An exploded diagram of Our newly developed S Series Ribbon Loudspeakers. The tweeter utilise a unique sandwich formation which projects a classically delicate ribbon sound, yet with modern loudspeaker power handling.
While Peter is often asked of his methods in loudspeaker design specifically when trying to appeal to loyal Quad customers, hi-fi enthusiasts and appreciators of good sound, he often refers to these core Quad values, similarly as Peter Walker had followed when developing our first products.
❱Tonal accuracy coupled to low distortion
In order to reach ‘The Closest Approach…’ the design of any QUAD component has to adhere to absolute tonal accuracy and minimal distortion. For example, in an amplifier, as long as the output signal is totally representative of the input signal, the amplifier has done its job.
❱Non-linear distortion in amplifiers
A traditional measure of ‘goodness’ in amplifiers is the measurement of Total Harmonic Distortion (THD). But, actually, harmonic distortion is of little consequence, even up to 2%. What really matters are the non-linear distortions, intermodulation, crossover and a host of other musically unrelated distortions which the ear picks up immediately.
❱Achieving linear performance under adverse conditions
QUAD amplifiers are designed to minimize the non-linear distortions under real-world conditions. For example the clever ‘output triples’ in the 303 power amplifier ensure that the output stage remains perfectly stable under extremes of temperature and dynamic voltage swings. Similarly the Current Dumping circuit achieves a perfect balance for the output stage thanks to its bridge balancing system.
❱Low distortion in loudspeakers
One of the main reasons for the development of the QUAD ESL-57 was Peter Walker’s objective to solve the problems of frequency linearity and low distortion in loudspeakers. At the time (1957) of its introduction, loudspeakers were the weakest link in the hi-fi chain. The QUAD Electrostatic loudspeaker neatly solved all the acoustic colorations endemic in box loudspeakers of that time.
❱So why do QUAD make moving coil loudspeakers?
QUAD’s earliest loudspeakers were moving coil designs, but with a difference. The 1950 Corner Ribbon used a true ribbon diaphragm for midrange and treble duties in order to produce a linear, low distortion output in this critical frequency range. Today QUAD’s latest moving coil speakers still adhere to this principle, using Computer Aided Design to reduce distortion in bass and midrange drivers and utilizing an advanced ribbon system for high frequencies.
❱Pushing the boundaries of design
Part of QUAD’s design philosophy has always been to utilize advanced design to make products that fulfil the needs of the consumer. Hence the sophisticated tone and filter controls of the QUAD 22 preamplifier, designed to achieve the best results from a myriad of source qualities from 78 rpm discs and reel-to-reel tape through to FM radio. Today the newest QUAD electronics maximize the performance from digital sources in easy-to-use systems that still adhere to the maxim ‘The Closest Approach To The Original Sound’.