Dougan Ref. K — by BV Audio
A three-way floorstander just over a metre tall, fronted by 25 kg of cast granite composite. Each speaker weighs about 85 kg, and most of that weight is doing something.
The design story ↓ Request an auditionFront elevation, to scale, from the working drawings.
01The baffle problem
Every loudspeaker has a problem it cannot escape: the drivers are bolted to the same panel that is supposed to stay still. A woofer moving nine millimetres each way pushes back on its frame with real force, and whatever that frame is attached to begins to move, flex and ring. On a wooden baffle you hear it as a thickening of the sound, a loss of midrange detail, a vague sense that the box is playing along.
The usual answers are more bracing, more thickness and more damping. We made the front of the speaker out of stone instead. ShtormStone is our own composite — crushed granite and quartz bound in engineered epoxy, from the same family of materials used for the beds of precision machine tools. It is dense, so the drivers push against real mass. It is stiff, so the panel does not flex between the fixings. And it is internally damped, so whatever energy gets in dies out quickly instead of ringing on, the way metal or glass would.
“Tap it with a knuckle and you get a dull click with nothing behind it. That is what the drivers are mounted to.”
A 40 mm ShtormStone baffle — about 25 kg02Modelled first
The acoustics were modelled before anything was drawn. We used AI-assisted modelling as a very fast, very patient engineering partner: it reviewed some thirty thousand finite-element iterations over 48 hours, and every part of the speaker was simulated, questioned and revised before a single sheet of plywood was cut. The shapes that fell out of that study are what you see.
Just under 60 litres, tuned to 30 Hz through two 65 mm front ports: bass to about 31 Hz with a lift of barely a decibel. The low tuning is deliberate. The speaker behaves near a wall, and you never hear the ports breathing.
A modal analysis mapped every standing wave in the chamber and how each one couples back to the cone. The answer was an egg: no parallel walls, a flat front, and a narrowing tip that feeds the back wave into damping where it works best.
The tweeter and midrange sit at different depths, so their sound leaves at slightly different times. We modelled the arrival for a seated listener and tilted the whole face back three degrees; the tweeter's recessed waveguide takes care of the rest.
The roundover grows from nearly nothing at the foot to wide and soft around the tweeter, where a sharp edge would be audible. The waveguide continues in cast stone to a 180 × 160 mm mouth, matching tweeter dispersion to the midrange. Almost impossible in plywood; in a cast material, free.
Along the way, every drawing went through independent review, with more than 150 findings tracked and resolved: clearances, glue joints, the depth of a screw. Even the ports are trimmed to length on the finished, measured cabinet, so the tuning is set on the real speaker rather than on paper. The modelling is a design aid, and we describe it as that. The final voicing is done the old way, with microphones, in a room, by ear.
03Cast, not cut
Every baffle begins with a master: the full face — waveguide, port flares, driver recesses, that changing edge — machined as one piece, then sanded, sealed and polished by hand. A mould is taken from it that captures the surface down to the polish. What goes into that mould, and exactly how, is ours. What comes out is 25 kg of stone that cures for days before we will touch it.
Then the flat faces are ground back, wet, until the granite shows through — every chip cut to a flat, polished section — and sealed in clear polyurethane. The waveguide and roundovers stay exactly as the mould gave them. The result is true terrazzo: real stone, a surface you want to run a hand over, and no two faces alike.
Where it comes from
The Ref. K was designed by an American engineer who made Russia his home, and every pair is built here. We hold the work to one standard — the kind you check with a straightedge and a measurement microphone, not the kind that shifts with the map. A speaker either measures right, or it does not leave.
04Under the stone
The midrange carries voices, so its enclosure is a separate instrument: a smooth egg-shaped cavity of about eight litres, cast into roughly 18 kg of the same mineral composite. The woofer's pressure never reaches it, the cabinet walls never touch it, and the stone around it does not flex.
The body is 24 mm Baltic birch — thicker than the usual 18 or 21, because stiffness rises with the cube of thickness. The sides cant inward, the front leans, and a window brace and sealed shelf divide the inside. Every joint is a machined rabbet or dado, so the box goes together square.
Both crossover boards mount inside a removable door at the back, away from the woofer's pressure field, alongside the terminal plate. Loosen ten screws and the entire electrical side of the speaker is in your hands. The drivers sit on cast-in metal inserts, not wood screws, so they come out and go back indefinitely. Two terminal sets: bi-amp it, or link them and run one amplifier.
05Take it apart
Every part of the Ref. K, in your browser: drag to orbit, pull the slider to take the speaker apart, and click any part to read what it does. The geometry comes from the working drawings, simplified for display.
On value
We do not know of another loudspeaker at this price — in Russia or anywhere else — with this much engineering behind it. If one exists, we would honestly like to hear it.
30,000 finite-element iterations reviewed in 48 hours · AI-assisted modelling of every acoustic decision · 150+ review findings closed before the first production pair
We have heard what three times the money buys. We are not worried.
800,000 ₽ per pair
One hundred pairs a year · each pair numbered
06Specifications
| Type | Three-way floorstanding loudspeaker, vented bass, sealed midrange |
| Drivers | 275 mm woofer, 182 mm midrange, 30 mm dome tweeter in a cast waveguide extension |
| Baffle | 40 mm cast ShtormStone, polished terrazzo face, clear two-pack polyurethane |
| Body | 24 mm birch plywood, CNC cut, canted sides, window brace, sealed shelf |
| Midrange enclosure | Egg-shaped cavity, about 8 litres, cast mineral block |
| Bass tuning | About 59 litres, 30 Hz, two 65 mm front ports (modelled) |
| Crossover | Passive, two boards, bi-amp ready, two terminal sets |
| Dimensions | About 1,100 mm high, 410 mm wide, 470 mm deep, on a 443 × 500 mm plinth |
| Weight | About 85 kg each |
| Production | Limited to 100 pairs per year, each pair individually numbered |
| Price | 800,000 ₽ per pair |
By commission
The Ref. K is the speaker we wanted to exist. If the one you want does not, we take commissions: the same stone process, the same modelling, a cabinet designed around one room and one listener. Tell us what you are trying to hear.
“We made the one part that must not move out of stone, and built everything else around it.”
Request an auditionAuditions by appointment — John Dougan, +7 903 220 0175
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