Article · Published 2026-10-18
The woods in a Demograf Audio chassis: seven species of the Caucasus and the Tian Shan
Clients often ask what a Demograf Audio amplifier, DAC or preamplifier is actually made of. Inside are tubes, transformers, capacitors and wire; around them, in many of our pieces, is a wooden chassis. These are the seven woods we work with: Fergana cherry, Transcaucasian beech, Tian Shan maple, Charyn ash, Semirechye oak, Alatau walnut and Kirghiz birch. Each bears the name of a landscape in the country that runs from the Caucasus to the Tian Shan and the Seven Rivers of Semirechye. Five are native trees of the Tian Shan and its foothills; the beech belongs to the mountain forests of the Caucasus; and the oak, as we explain below, is a European tree long at home in the parks and avenues of Semirechye. This article describes where each grows, what kind of timber it gives, and what a wooden chassis can and cannot do for the sound.
Why wood in an amplifier chassis?
A chassis carries the transformers, holds the tube sockets and sits between them and the shelf. It is part of the mechanical system of the amplifier, and its material decides how vibration travels through it.
Vibration inside an amplifier
Two kinds of parts in a tube amplifier are sensitive to vibration. Transformers and chokes hum mechanically: their laminations move with the magnetic field, at twice the mains frequency and its harmonics, and pass that movement into whatever they are bolted to. Tubes are microphonic: when the glass and the electrodes inside vibrate, the spacing between the electrodes changes very slightly and the signal is modulated with it. Small-signal tubes in high-gain stages and directly heated triodes are usually the most sensitive. Sound from the loudspeakers also reaches the chassis through the air and the floor.
Wood compared with metal
Steel and aluminium are stiff and strong, but have very little internal damping: tap a metal panel and it rings. Wood dissipates vibration inside its own fibres; its internal damping is typically an order of magnitude or more higher than that of steel or aluminium, and a tapped hardwood panel gives a short, dull knock. In a chassis this means that energy from a transformer or from the room tends to die away in the wood rather than ring through the structure to the tubes.
Wood is neither magnetic nor conductive, so it does not interact with a transformer’s stray field, but it also gives no electrical shielding. A wooden chassis therefore needs a proper ground scheme and, where a circuit calls for it, metal plates, shielded transformer covers or a metal sub-chassis. The two materials are often combined; the catalogue describes the chassis of our Prometheus DAC, for example, as hardwood and metal.
Heat and humidity
Wood insulates heat rather than spreading it, so a wooden chassis needs clearances and ventilation around tubes and power resistors, with the hottest parts on metal. Wood also swells in damp air and shrinks in dry air, some species far more than others, so chassis timber is dried slowly, rested and finished on every face. After shipping from one climate to another, let a wooden piece acclimatise before switching it on, and keep it away from direct heating or cold drafts.
Does wood affect the sound of an amplifier?
Honestly: indirectly, and usually subtly. The signal never passes through the wood. What the wood changes is how vibration reaches and leaves the tubes, transformers and circuit board, and how the enclosure itself resonates. How much that matters depends on the circuit, its tubes, the listening level and how close the amplifier stands to the loudspeakers. In a well-designed amplifier the difference between two good hardwoods is small, and far smaller than the difference between two loudspeakers or two rooms. We make no claim of measured improvements from any wood.
The characters listeners attach to different woods come largely from instrument making, where the wood itself radiates sound: the maple back of a violin, the ash body of an electric guitar. In an amplifier the wood is not a soundboard, so read them as associations, not rules. The table sums them up, with approximate densities for air-dried timber.
| Species | Density, approx. | Hardness | Figure | Typical use in a chassis | Character often attributed |
|---|---|---|---|---|---|
| Fergana cherry | 550–650 kg/m³ (cherry woods) | Medium | Fine, even; deepens to red-brown | Fronts, small panels, inlays | Warm, smooth |
| Transcaucasian beech | 700 kg/m³ | Hard | Fine, even, with ray fleck | Frames, bases, internal structure | Neutral, even |
| Tian Shan maple | 600–700 kg/m³ (maples) | Hard | Fine, pale, sometimes curly | Top plates, small panels, inlays | Clear, articulate |
| Charyn ash | 680 kg/m³ (European ash) | Hard, tough | Open, bold growth rings | Frames, side panels | Lively, open |
| Semirechye oak | 720 kg/m³ | Hard | Open, silver ray figure | Bases, plinths | Firm, dense |
| Alatau walnut | 640 kg/m³ | Medium-hard | Brown, dark streaks, sometimes burl | Whole chassis, panels | Warm, balanced |
| Kirghiz birch | 640 kg/m³ (silver birch) | Hard | Pale, fine; sometimes curly | Cores, panels, pale inlays | Even, neutral |
Densities are typical figures for the species or, where published data for it are scarce, for its closest well-studied relatives, named in brackets; boards vary widely.
Fergana cherry (Prunus tianschanica Pojark.)
Where it grows
Prunus tianschanica, the Tian Shan cherry, is a wild cherry of Central Asia, described by the botanist Antonina Poyarkova and also placed in the genus Cerasus. It belongs to the dry foothills and lower mountain slopes of the western Tian Shan, including the ranges that ring the Fergana Valley, the wide basin shared by Uzbekistan, Kyrgyzstan and Tajikistan, where summers are long, hot and dry. It is not the tall orchard sweet cherry but a low, many-stemmed shrub or small tree of stony ground, covered in pale blossom in spring and bearing small fruit in summer.
The wood
Its stems are slender, so its wood comes only in small pieces, and published timber data for the species are scarce. The cherry woods that have been studied are fine-textured hardwoods of medium density, roughly 550–650 kg/m³, with a straight grain that machines and sands cleanly. Their pale pinkish-brown heartwood deepens with light and age to a warm reddish brown, so a cherry part keeps changing colour for years. Cherry dries without much trouble and takes oil and wax finishes well.
Its role in a chassis
Small sizes and a warm colour make it a wood for fronts, small panels and inlays rather than for structure. Listeners and instrument makers commonly describe cherry as warm and smooth.
Transcaucasian beech (Fagus orientalis Lipsky)
Where it grows
Oriental beech, described by the botanist Vladimir Lipsky, forms great forests on the mountain slopes of the Caucasus and Transcaucasia: in Georgia, Azerbaijan and Armenia, in the Hyrcanian forests along the Caspian shore of Azerbaijan and northern Iran, and in northern Turkey and the eastern Balkans. These wet, misty forests face the Black Sea and the Caspian and rise to roughly 2,000 metres; under the closed canopy the tall grey trunks stand in their own shade.
The wood
Beech is dense and hard, around 700 kg/m³, close to its European cousin. Its texture is fine and even, and boards show small, dark flecks where the medullary rays are cut. Pale cream by nature, it turns a warm pinkish brown when steamed. It holds screws and threaded inserts well but is one of the less stable hardwoods, moving markedly with humidity, so it is dried slowly and rested before machining.
Its role in a chassis
Beech is a structural wood. It suits frames, bases and the internal structure that carries transformers, often under a more decorative species. Its character is commonly described as neutral and even: it is chosen for what it does more than for how it looks.
Tian Shan maple (Acer semenovii Regel & Herder)
Where it grows
The Tian Shan, the “Celestial Mountains”, run for about 2,500 km from Uzbekistan through Kyrgyzstan and Kazakhstan into Xinjiang in China, with peaks above 7,000 metres and glaciers that feed the rivers of the plains below. Semenov’s maple, named after Pyotr Semyonov, the geographer who explored the Tian Shan in the 1850s, is one of its native trees: a small tree or tall shrub, often many-stemmed, of the Tatar maple group, and some botanists treat it as a subspecies of Acer tataricum. It grows in the Tian Shan, the Dzungarian Alatau and the Pamir-Alay, in foothill gorges, along streams and on slopes up into the mountain forest belt, with cold winters and short, bright summers.
The wood
A small tree gives small timber, and published data on this species’ wood are scarce. Maples in general are hard and fine-textured, roughly 600–700 kg/m³. Maple wood is pale cream to light honey, and some trees show a curly figure that shimmers as the light moves. Slow mountain growth gives tight rings; maple dries well, is reasonably stable and takes a very smooth finish.
Its role in a chassis
Maple is the classic wood of violin backs and ribs and of guitar necks, and instrument makers commonly describe it as clear and articulate. In a chassis it is used for top plates and small panels, and as a pale inlay against darker woods: the cabinets of our Orpheus loudspeakers, for example, are finished as standard in walnut veneer with maple inlays.
Charyn ash (Fraxinus sogdiana Bunge)
Where it grows
Sogdian ash, described by the botanist Alexander von Bunge, grows along the rivers of Central Asia, from Uzbekistan, Tajikistan and Kyrgyzstan to south-eastern Kazakhstan and the Ili valley in Xinjiang, where it tolerates summer heat as long as its roots reach water. Its most famous stand is the relict ash grove on the Charyn River in Kazakhstan, a remnant of forests far older than today’s steppe. The river runs through a canyon of red and ochre cliffs, and the grove is a green ribbon along its banks. The grove lies within the Charyn National Park and is protected: it is not a source of timber. Our Charyn ash is named after the species and the landscape it belongs to.
The wood
Published data on Sogdian ash timber are scarce; its properties are taken to be close to those of European ash, around 680 kg/m³. Ash is hard, tough and elastic, long used for tool handles and bent wood. It has a coarse, open texture with bold growth rings, a pale cream to light brown colour, dries fairly easily and is moderately stable.
Its role in a chassis
Ash suits frames and side panels where toughness and a visible grain are wanted. In electric guitars it is commonly described as lively and open.
Semirechye oak (Quercus pedunculata Ehrh.)
Where it grows
Semirechye, Zhetysu in Kazakh, is the “Land of Seven Rivers” in the south-east of Kazakhstan: a plain that runs from the shores of Lake Balkhash up to the Dzungarian and Trans-Ili Alatau, crossed by the Ili and the rivers fed by mountain snow. Quercus pedunculata is the pedunculate oak, known today by its accepted name Quercus robur L.: the oak of European forests. To be precise, no oak is native to Semirechye. Pedunculate oak has been planted in the region’s towns, parks and shelterbelts for well over a century and thrives there in hot summers and cold winters.
The wood
Oak is heavy and hard, around 720 kg/m³. It is ring-porous with a coarse, open texture, and quartersawn boards show the broad silver figure of its medullary rays. Its tannins react with iron and moisture to leave black stains, so an oak chassis uses brass or stainless fittings. Once slowly seasoned it is reasonably stable.
Its role in a chassis
Mass and stiffness make oak a natural choice for bases and plinths: the part of a chassis that carries the heaviest transformers and stands on the shelf. Its character is commonly described as firm and dense.
Alatau walnut (Juglans regia L.)
Where it grows
“Alatau” means “mottled mountains”, and it is the name of several ranges of the Tian Shan, among them the Trans-Ili, the Kyrgyz and the Talas Alatau, and of the Dzungarian Alatau to the north. The common walnut grows wild in the walnut-fruit forests of the western Tian Shan, on the slopes of the ranges above the Fergana Valley and in the far south of Kazakhstan, alongside wild apple, pear and plum. These forests are among the places where the species grows naturally, and what remains of them is protected. Across the foothills, including those of the Trans-Ili Alatau, it has also been planted for centuries in gardens and orchards.
The wood
Walnut has a density of around 640 kg/m³ and is medium-hard. Its heartwood is a grey to chocolate brown with darker streaks; the burls and the wood near the root give the swirling figure prized for veneers. Walnut is very stable once dried, long used for gunstocks and fine furniture, and takes an oil finish with a deep lustre.
Its role in a chassis
Walnut balances weight, stability and appearance, so it can make a whole chassis as well as its panels. Its character is commonly described as warm and balanced, and walnut veneer is the standard finish of our Orpheus loudspeakers.
Kirghiz birch (Betula kirghisorum Sav.-Rycz.)
Where it grows
Kirghiz birch is a native birch of the Tian Shan, named after the Kyrgyz people. It grows in the valleys of the Tian Shan in Kyrgyzstan and neighbouring Kazakhstan, along mountain streams and on moist slopes. Like other birches it is a light-loving tree with white bark, quick to take to open ground. Botanists still discuss how the birches of Central Asia should be divided into species.
The wood
Published data on this species’ timber are scarce; birch wood in general is pale, fine and even in texture, diffuse-porous and tough, with a density of around 640 kg/m³ for the well-studied silver birch. Some trees show a curly or flame figure. Mountain trees are modest in size, so boards are not large. Birch glues and machines well and holds fittings firmly, which is why it is a classic core wood for plywood and veneered panels.
Its role in a chassis
Birch suits cores and internal panels under a decorative veneer, and pale panels and inlays of its own. Its character is commonly described as even and neutral.
How the wood for a build is chosen
Every Demograf Audio piece is made to order, and the wood is chosen for each build together with the client. Appearance and the room matter, and so do the climate, the weight the chassis must carry and the heat it must live with. A common approach in wooden chassis is a dense, stable hardwood for the base that carries the transformers and a figured wood for panels or inlays. The catalogue lists the options for each model, from a classic wooden chassis to exotic hardwoods and wood inlays; the atelier page describes how a commission is made.
Which Demograf Audio piece fits
- A tube amplifier in wood: Tantal and most of our other tube amplifiers can be ordered with a hardwood chassis or wood inlays.
- A preamplifier: Hector comes in a wooden chassis in its stock form.
- A DAC: Prometheus combines hardwood and metal, and Hyperion can be made in hardwood to order.
- Loudspeakers: Orpheus is finished as standard in walnut veneer with maple inlays, with a custom solid-wood cabinet on request.
Every piece is made by Dmitriy Gubchenko, with a one-year warranty (extra warranty available: +1 or +2 years). Our guide to tube life and care covers microphonic tubes, and our glossary of hi-fi terms explains the other words used here. Tell us about your room, your climate and the look you have in mind, and we will suggest a wood for your build.