The Stirling Broadcast BBC LS3/6 Reference Loudspeakers are a new 3-way loudspeaker design for Stirling Broadcast by Derek Hughes to be as close to the original BBC LS3/6 specification possible with modern components. Released in December 2011, this new model was built under licence from the BBC, only possible after submission to the BBC for rigorous examination to ensure they adhered to the original specification.
The original Stirling Broadcast LS3/6 Loudspeaker was designed as a monitoring loudspeaker for outside broadcast use, as with the smaller LS3/5a speaker. Once the design was finalised Rogers became one of the first companies to produce this complicated design. A summary of the history of the design can be found on our’s website.
Stirling Broadcast LS3/6 Sound
But if these general principles are worth noting, still in the end the devil is in the details. One could surely make a speaker of this general type that would not have the remarkable sonic quality of the LS3/6. Derek Hughes has done a wonderful job of carrying the unforgettable sound of the original into the modern era. And most wisely he has firmly resisted the idea of modernizing the speaker in the negative sense of making the bass amusically tight and removing the warmth and fullness of the original. While the bass is less loose than my recollection of the Spendor BC- 1, the Stirling Broadcast LS3/6 still gives a warm full sound, indeed, with good pitch definition as well. The LS3/6 will please the appreciators of the low mids/upper bass of the original and at the same time will make new converts among those not coming at it from past glories.
Similarly, the Stirling Broadcast LS3/6 remains determinedly not excessive in the top end. Top-end extension there is, but aggression that is all too often the modern style there is not. (Strictly speaking, there is a little perceived roll-off at the truly extreme top, but this is musically inconsequential and perhaps even advantageous in practice.) And the midrange itself remains in the top echelon for a combination of clarity , resolution, and neutrality. And perhaps most of all, coherence – there is no crossover like no crossover, and the LS3/6 speaks with one voice over what amounts to almost the whole range of music.
Since one of the strengths of the BC-1 was string sound, I decided to play as my “first impression” the Budapest Festival Orchestra/Fischer recording of Dvorák’s Nocturne for String Orchestra on Philips, one of my current string-sound favorites. Talk about putting a smile on one’s face! This is the kind of music I play myself all the time – I belong to a chamber orchestra that plays a lot of pure string music. And the real sound was much in evidence here. The feeling of hearing the sound I hear at my rehearsals was considerable, to say the least.
Next I tried Bis’ masterpiece of piano recording, Freddy Kempf playing Rachmaninoff’s transcription of Kreisler’s Liebesleid. The realism of the piano was most striking, and the beauty of it, too. And the micro-structure of the piano notes, their complex attack and decay and interplay of overtones, was remarkably convincing. Indeed, one could not help feeling that there is some real magic in having a single driver cover so much of the musical range – and cover it so well.
On orchestral music, the Stirling Broadcast LS3/6s has both a compelling tonal naturalness and a striking level of what I might call “informativeness.” Often speakers give perceived detail because of an exaggeration of some area of high frequencies. But the LS3/6s offered unusually detailed information about complex music without treble exaggerations. Indeed, this persisted even if I deliberately turned down the treble with an EQ device below its natural, correct level. The LS3/6 really does have, it seems, an intrinsically high level of information-transmission on complex music. Every individual instrumental line in the Rachmaninoff Symphonic Dances (Proarte, Dallas, Mata) and in the Dvorák New World (Delos, New Jersey, Macal) was made extraordinarily clear, as was the reverberation of the individual lines. Things like the separation between say a trumpet call and the hall’s response to it were revealed exceptionally well. Textures were all naturally presented and very cleanly articulated. But none of this involved any aggression in the sound at all – it was just detail as it naturally occurs.
Attached to this is an unusual kind of perceived dynamic punch. Speakers seldom exhibit literal dynamic compression until quite high levels are attempted. But things like snare drum strokes come out especially well-defined on the Stirling Broadcast LS3/6. Even at low levels, where literal compression could not be an issue, the LS3/6s give a special articulation that comes across as dynamic excitement. Perhaps this is attached to the fact that the signal is undivided over most of the range, with the sound coming from a single driver. In any case, for what ever reason, the effect is there. This and the sonic impressions of the previous paragraph suggest yet one more time how well the BBC “lossy” cabinet construction idea actually works, a point that tends to escape most contemporary designers, who are enamored of “rigidity” on what often seems a reflexive basis.
You can hear the effect I am referring to on that old standby, Opus 3’s Tiden bar gaar, where the drumming and plucking have unusually clean and articulate character and sound unusually “dynamic” for lack of a better word (though dynamics are not what is literally involved), without being over-etched in the least. And comes to that, the (Swedish) words are unusually well articulated as well and the voice has a very natural quality.
And the LS3/6s can play loudly, as noted above. They are easily capable of satisfying orchestral levels in a room of moderate size, with dynamic capacity to spare. With well over 100dB levels possible without strain at 2m, I felt no dynamic constraints at all in my 14′ by 27′ living room. I could blast away if I wanted to, with headroom to spare. With a subwoofer or two, volume capability could be extended even further but for me, adding subs would be for only ultra-deep bass extension, not for the sake of higher levels. The Stirling Broadcast LS3/6 is a much more robust speaker than the original Spendor BC-1 and plays far louder without difficulty – one of the things modern drivers can do better than earlier ones!
The LS3/6s deal successfully with the floor interaction in the low midrange and upper bass. They sail down from 300Hz into the 40Hz region with no dip and no weakness, in contrast to the “floor dip,” the hole in response between 100 and 300Hz, that all too many other speakers exhibit. The LS3/6s thus give the orchestra the proper weight, substance, and solidity. And as with the Spendor SP1/2, DSP correction here finds nothing to correct. And this happens with almost any reasonable setup: It is not a matter of inch-by-inch tweaking. This is a design that just works, although, of course, like any speaker it has to be placed reasonably. The proper performance in the 100 to 300Hz region is crucial to the correct perceived balance and feeling of realism and musicality of full-range music. And here you get it. Bravo!
Incidentally, while the grilles of the LS3/6 can be popped off without much difficulty, I recommend not doing so. Grilles off brings up 6–7kHz a little and makes the sound less accurate tonally without actually giving any more in the way of real detail. To the extent that the (lower) tweeter is not absolutely smooth, it has a little hint of excess around 6–7 kHz, and to remove the grilles is to bring this to the fore. With the grilles on, much better, indeed excellent, smoothness is attained. And the removal of the grilles exposes edges in a way not, I should think, to advantage in terms of diffraction. Leave them on!
I do not have a pair of BC-1s or original LS3/6s in functioning condition. But I do have a pair of Spendor SP1/2s in good order, Derek Hughes’ design from the early 1990s in the same general style – same driver configuration, same box size, itself a lineal descendent of the original BC-1/Stirling Broadcast LS3/6 design. The speakers are similar but the exact balance is a little different, with the SP/2s having a bit more energy in the 1–2kHz octave than the LS3/6. Even within neutrality as commonly understood, there is room for variation! The Stirling Broadcast LS3/6 has a more precise, slightly crisper sound, with a little more perceived definition, the SP1/2 has a perhaps even more precisely correct rendition of instrumental sound and a slightly smoother treble, set at a slightly lower level. A close call to choose between the SP1/2 and the LS3/6, down to the point where room conditions would make the difference perhaps. Both great speakers, and clearly from the same family! (The current Spendor model called SP1/2R2 is a quite different speaker: see Issue 218.)
The Stirling Broadcast LS3/6 takes advantage of the greater consistency and linearity of modern drive units compared to when the LS3/6 was originally designed. A very high quality crossover is used to mesh custom made drive units, including a super-tweeter, into thin-wall, birch plywood (9mm ply) cabinets with double thickness rubber damping pads and screw-on, removable front and rear panels, as per the BBC lossy” cabinet design ideal as also seen in the Stirling version of the LS3/5a.
This new version offers greater power-handling than the original versions from the 1970 and 1980s and offers the smooth frequency response very low colouration and good dispersion commensurate to addearing to the specifications of a BBC monitor.
Bookshelf speakers in the loosest definition of the phrase the Stirling Broadcast LS3/6 stand proud at 24″ high 12″ wide and deep. An exciting addition to the Stirling Broadcast range to compliment the smaller LS3/5a speakers (see photo above for illustration of how they compare in size). For the best sound use these speakers with 400mm high stands.
Installation and setup
Perhaps it was good design, good luck, good instincts, or some combination of all three – whatever the cause, the time I spent setting up the Stirling LS3/6s was brief and untroubled. Blessedly, their stands required no assembly, apart from screwing optional spiked feet in the threaded inserts at the bottoms of their feet. And because thin rubber pads were pre-installed on the top surfaces of the stands, I didn’t ever have to subject myself to the drudgery of rolling little bits of Blu-Tak into pea-size balls, as one must do with virtually every other stand of this sort.