Re: BBC LS5/12a
The LS5/12A was not actually designed by or connected with the BBC Research Department in any way, so it shares nothing with the classic BBC designs from the 1960s and from which today's Harbeths are directly descended.
As I recall it, the 5/12 was designed as a personal out-of-hours project by a BBC engineer in Equipment Department without management sanction. In fact, when Research Dept. became aware of what was going on they were not amused as senior management had decided some years previously, and after Harwood retired to found Harbeth, that 'there would be no more in-house BBC monitor development'. So, unsurprisingly, Research were not in a position to do anything other than stand back and watch, and certainly not to provide resources or staff to critique the design.
The designer told me that his concept was to 'clone the sound of the much bigger LS5/8, but in miniature'. I believe that he achieved this: certainly when I heard an A/B at Equipment Dept. of the LS5/12A v. LS5/8 I agreed that they sounded remarkably close in tone. Whether the LS5/8 was the reference to aim for I did wonder because as noted the P3, then a couple of years into production, seemed to offer a more open sound with better bass (sealed cabinet; 5/12 was vented and more difficult to place near walls) and at about half the price. Consumer domocracy decided which was better value.
When we agreed to take the licence we were not permitted to keep the reference speaker that they brought us: we had to say yes or no based on a short audition in our listening room. Some weeks later the approved master reference unit arrived (just one piece) and we set about really analysing the design. This is where the problems started. It was clear that as the core components had already been defined, that at best, any changes would have to be peripheral and the design was substantially reworked at my insistence into the LS5/12A. Had I - or Research Department - been privy to the design process we could possibly have steered the design in a different direction and, as with the previous true BBC monitors, designed core parts rather than bought them in. But as I've explained, Research dept. were not in the loop.
The 5/12A certainly has its fans: it seems to be popular with those fond of choral music. Whether the performance is the same now as when we made these in the early 1990s I'm not sure. We have no spare parts available.
Alan A. Shaw
Harbeth Audio UK