Thanks to a commission from Sound On Sound to write a feature on the fabled BBC LS3/5A monitor  (combined with a review of the Graham Audio Chartwell LS3/5), I found myself extensively researching the story of the speaker. I mean, the last thing I needed to do when writing about the ‘3/5A was to get anything wrong and be taken to task by a pack of exasperated audio geeks. Like, I suspect, most British hi-fi enthusiasts of a certain age, I already knew the bones of the LS3/5A story. In bullet point form it goes like this:

• Speaker derived from one designed for acoustic scale modelling found to be really good for use in mobile studios so is developed into a viable compact monitor.
• In-house BBC demand means that commercial manufacture of the speaker is needed.
•  BBC offers licences for manufacturers to sell the speaker commercially to domestic customers (income from the licence sales helps pay for the speaker’s development).
• Around 100,000 pairs are made by various manufacturers over a couple of decades or so, and the LS3/5A, primarily thanks to it’s uncannily natural voice and mid-range character, wins the hearts and ears of audiophiles everywhere.
• Four decades on, the LS3/5A refuses to die. Contemporary interpretations and reincarnations abound and an early original pair sells for over £12k on eBay (although one wonders if the deal actually completed).

But of course, the LS3/5A back-story has all manner of interesting (to me, anyway) nuggets. For example….One of the research resources I used while writing the Sound On Sound feature was an archive of BBC technical reports. Along with many other fascinating documents, dating back to the earliest days of the Corporation, the archive includes a 1976 report on the development of the LS3/5A by Dudley Harwood (who later went on to found Harbeth Acoustics), Marice Whatton and Ralph Mills. The LS3/5A (perhaps the earliest common ancestor of all compact speakers that aspire to genuine high performance – discuss) however wasn’t the first compact monitor to have come out of the BBC R&D department. The archive also includes a document, from seven years earlier, describing effectively the LS3/5A’s predecessor: the LS3/4. The LS3/4 report was again written by Dudley Harwood but this time his co-author was Spencer Hughes, who was soon to leave the BBC to found Spendor. So the LS3/4 report records the founders of two hugely influential British speaker companies working, and developing their electro-acoutic craft, together.

The LS3/4 report is however more than just a curiosity of the formative years of the British speaker industry. It includes a bunch of response and distortion measurements that suggest the LS3/4 was actually, especially considering it was a product of the late 1960s, a pretty reasonable speaker. I can’t quite make up my mind if the LS3/4 was unusually good or if, here in 2016, we’ve actually not really got much better at speaker electro-acoustics.