HIFICRITIC - audio review magazine

17th June, 2014

Interpreti Veniziana

Interpreti Veneziani
at St John’s Smith Square, London
The small Venetian Italian string band invited to perform in London by sound engineer and producer Mike Valentine.

11th March, 2014


CLARITY:  Spring Conference 2014

The UK Trade Audio association, Clarity hosted their annual spring conference on February 10th and a regular feature, a review of the consumer audio business for the UK, was presented by GFK. It covers the whole electronics market including appliances and then subdivides into consumer electronics, Hi Fi Separates, Streaming, Connected audio and Wireless speakers, Soundbars and Headphones.

 From mid 2013 it was clear that consumer confidence was at last improving for the UK market, tracking the now falling unemployment figures.  However for 2013 domestic appliance growth was the more significant while consumer electronics and photographic sales continued to fall, if at a slower rate. The main falls were in MP3 Stereo, Home theatre, Blu-ray and in-car. Conversely household and kitchen electrics rose 10%.

As in recent years online sales continued to grow e.g. by 20% for ‘home audio’, though more costly hi fi separates are likely to figure very little in this change.  For TV Soundbars continue to show a striking 100%  growth this displacing lower  ranked and costly  5.1 arrangements. Soundbars have replaced docks in the growth stakes rising from 28,000in ’09 to 67,000 in 2011 to 500,000 by end 2013. Soundbases are growing but are still running at just 40,000 units per annum.

For audio while sales of lower cost amplifiers, receivers, and portable MP3 were falling at between 20 to 40%, more expensive headphone sales held up, while connected audio and audio systems, docks and the more costly headphones increased their sales volume.

 While Hi Fi separates (here including Soundbars) had peaked at £419m in 2001 and had fallen to about £170m for 2010-2012, surely by the end of 2013reflecting the depth of the recession, they are now on the rise to £221m, almost back to the 2005 pre recession level. We should perhaps note that here the sound bar contribution is substantial.  500,000 Soundbars were sold in 2013, just over double the previous year by value and some 2.5times greater by volume.  Whilst talking about TV, the average panel screen size is still rising, from 21.5” in 2000 to 25.4in for 2005, to 30in for 2010 to 33.3in for 2013. 

 Bluetooth connectivity took 82% of the streaming audio component market by value in 2013 and is still growing while by contrast Airplay barely lifted off the near zero line.

From a historically low baseline the still significant analogue turntable market, remains in slow decline though it had more recently peaked at 74,000 units for 2010 beating the recession.  It nevertheless remains respectable for 2013 with 48,000 units sold. The present sales value of this sector held at £7 million for the UK, this almost matching the 2010 figure by value.

Products (including smartphones) that can stream and control audio to sound systems grew massively for 486,000 to 1.88 million units in the past two years. This is spurring growth in generalised connected home audio of all kinds.

 Headphones showed a split from the trend actually falling by about 15% both by volume and value from 2012,  partly felt to be due to approaching saturation, as nearly 55% of consumers already have a set.

However in this market cordless or wireless versions showed real growth especially from Bluetooth equipped models: another reflection of the increasing popularity of cordless control and connection.

A further finding was the heavy saturation of models in the UK headphone arena with 80 types now competing for every single headphone demo space in shops! Some brands are helping to pay for their retail space, squeezing out smaller operators.

 Showing the fickle nature of the mass headphone market, food supermarkets became major suppliers with an 18% growth by value. Conversely while online headphone sales held, in-store headphone purchases fell a surprising £27 million last year. Encouragingly for high fidelity items, here the 2013 growth sector was for models over £150;    sales of higher quality audio separates remained steady.

Martin Colloms  

23rd November, 2013
Decca Studios and Klooks Kleek

Decca Studios and Klooks Kleek
Book Review by Paul Soper: (reprinted with permission Nov 2013)

16th May, 2013
MUNICH 2013 Show Blog


28th February, 2013
Bristol 2013 Show Blog


9th January, 2013

A classic text unexpectedly revised:

Acoustics: Sound Fields and Transducers by Beranek and Mellow

ISBN-13: 9780123914217, Elsevier Science, 0/4/2012 720PP

I first encountered Leo Beranek’s book Acoustics while researching material for High Performance Loudspeakers which first edition was published in 1976/77, when Acoustics had been in print for some 20 years. Now, more than half a century later and encouraged by Tim Mellow, Beranek and Mellow have collaborated to produce a new edition of Acoustics, founded on the original classical fundamentals but with a modern slant more clearly focused on electroacoustics and carrying the sub-title, Sound Fields and Transducers.

Leo has enjoyed a long and distinguished career in acoustic design and consultancy, particularly at Bolt Beranek and Newman, BBN. He has published 13 books and has also been involved in broadcasting as well as the precursor technology to the internet. Tim graduated in 1985 in Electronics and Electrical Engineering at the University of Dundee and has published a number of papers on sound radiation. His enthusiasm for loudspeakers led him to the electrical circuit analogies for electroacoustic transducers in Leo’s book; (these associated with the radiation acoustics that complete the circuit from electrical audio currents to radiated sound energy). Tim enthusiastically proposed a new edition of Acoustics to Leo, which after some extended discussions, was agreed as a joint authorship project.

The 2012 edition of Acoustics runs to 704 pages. The first 4 chapters comprehensively deal with acoustical fundamentals, leading to microphone theory and practice in chapter five. Electrodynamic loudspeakers are covered in chapter 6, followed by loudspeaker systems and enclosures in chapter seven. Cell, mobile phone transducer technologies are introduced in chapter eight, leading to a strong chapter nine on horn loudspeakers. This includes an example of a rectangular 7.5cm by 3.9cm treble horn, +/-3dB, 1.5kHz to 10kHz, which provides a typical sound pressure gain of 16dB into a defined radiation angle, a welcome reminder of horn efficiency gains. Chapter ten covers ‘enclosures’, here the design of rooms and halls, followed by a brief look at listening room issues in eleven. From twelve onwards we return to theory where Mellow’s speciality, acoustic radiation and scattering from a variety of theoretical sources in particular situations, comes to the fore.

In chapter twelve the boundary value method is employed while in 13 one can see the contrast with the boundary integral method, here used more comprehensively. These many analyses include some of the issues faced when mounting a high frequency driver on a contoured section of a loudspeaker enclosure. Interesting and relevant examples include the radiation of a spherical cap on a sphere, and radiation from an infinite line source.

In Chapter fourteen, state variable analysis is applied to numerous loudspeaker equivalent circuits, facilitating computation from first principles. Finally, there are some useful appendices, tables, design summaries and conversion factors.

The book is aimed at electroacoustic students and engineers active in transducer and loudspeaker system design. There is an emphasis on understanding the fundamentals, providing sufficient classic example problems for the designer to apply to new product. It won’t tell you how to design a commercial hi fi loudspeaker, but if you have the skills it can explain much of the relevant electroacoustic behaviour from first principles. Designers will find numerous alignment tables, charts, graphs, formulas and worked examples in Chapter 7, for example the complete behaviour of a driven bass reflex enclosure including the higher modes, a useful starting point though understandably not including structural behaviour.

Proficiency in mathematics is a help; this reference work could be regarded as the counterpart to the advanced, computational acoustic engineering software such as Comsol now becoming popular, providing much of the grounding for these multi discipline, coupled modelling programs, while inexpensive math programs such as Mathematica may be deployed to calculate the extensive models supplied in the work

It is a welcome surprise to see Leo Beranek’s Acoustics so exhaustively revised while we also have to thank co author Tim Mellow for his deep commitment to the work.

Martin Colloms
Technical Editor HIFICRITIC Jan 2013

Sound and Vision Bristol 2013

See us at Bristol Sound and Vision show 2013

16th October, 2011
NAS 2011 Show Report

NAS 2011 Audio Show Blog

by Paul Messenger

12th September, 2011

HIFICRITIC: The Rhythm King DIY Loudspeaker

Designed in the first half of 2011 by Martin Colloms, Christien Ellis (CE Electro-Acoustics, and Miles O’Carroll ( The Rhythm King has passed its proving trials and is ready for demonstration at the National Audio Show September 24/25. Room S15 with ticketed presentations on the design principles involved.

TRK The Rythm King Speaker
This speaker is designed for wall boundary matching and a neutral timbre.

Wilmslow Audio built the enclosure to drawings created by Miles O’Carroll from design sketches by Martin Colloms and Christien Ellis.  Wilmslow Audio have agreed to supply all the parts required including the exclusive supply of the Cotswold Acoustics manufactured, BMR full range planar driver. The custom made Multi-Contact terminated  solid core  internal and external wiring harnesses are built by DNM Design and work with external, easily updated crossover networks.  

TRK Crossover Prototype
The first working prototype crossover

This site has the first article describing the approach to design form Vol. 5 No 1; the second concluding part will be published in September 2011,   HIFICRITIC Vol. 5 No 3 and will be copied to this site soon after.

Also see the comprehensive measurements, the crossover circuit with preferred wiring topology and related illustrations, the full enclosure drawings file and related material.

Please send questions and comments to the DIY speaker section of the HIFICRITIC Forum which also has some early description.


26th August, 2011

National Audio Show
HIFICRITIC Exhibits the DIY TRK Loudspeaker at the
 National Audio Show 2011, Whittlebury Hall, Sept 24/25
TRK, The Rhythm King will be demonstrated at NAS, with ticketed presentations on the design process by Martin Colloms. The design team will be on hand to take questions. Co-exhibitors are Wilmslow Audio who supply the parts and DNM Design who supply the special cables, inside and out. HIFCRITIC will also have their usual stand in Brooklands with show discounts on subscriptions and back numbers and where tickets may be obtained for the design presentations. The concluding issue for the unique HIFICRITIC loudspeaker project will be on sale, hot off the press.
HIFICRITIC-Wilmslow-DNM  ROOM:  S15,  1st Floor 

National Audio Show 2011

National Audio Show
HIFICRITIC Exhibits the DIY TRK Loudspeaker at the
National Audio Show 2011, Whittlebury Hall, Sept 24/25

9th April, 2011

Audio World 11 Show Report:

The Spring Audio Show at the Heathrow Park Inn

27th/27th March 2011

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