Tendens
A portable concert instrument developed to deliver maximum musical authority, clarity, and control — without the compromises of traditional concert grands.
The Instrument
A New Category of Concert Piano
Tendens is a ballistic concert piano — a true member of the piano family, not a digital surrogate and not a traditional grand.
Tendens is a portable concert instrument that does not fit existing categories. Where digital instruments reduce playing to abstract control data, and traditional concert grands depend on massive mechanical inertia, Tendens restores the direct physical relationship between pianist and sound — without the weight, fragility, and constraints of 19th-century instruments.
Ballistic Response, Not Velocity Playback
Traditional digital pianos are velocity instruments: the musical result is determined by how fast a key is pressed.
Tendens does not work that way.
Tendens responds to how the hammer is launched — the timing, acceleration, and release of energy — sharing the same physical language as a world-class acoustic grand. The instrument reacts to the pianist’s intent instead of correcting or abstracting it.
What you play is what the instrument receives.
Dialogue Between Artist and Instrument
At the core of Tendens is the restoration of true dialogue.
A musical instrument should not impose outcomes. It should respond.
You act, it answers — and that response meaningfully informs the next gesture.
Most electronic instruments offer a monologue: a pre-shaped result delivered to the player. Tendens allows real-time negotiation of touch, timing, resistance, and colour. This mutual sensing is what makes an instrument feel alive, turning mechanical input into musical expression.
An Active Soundboard, Not a Speaker
Conventional electronic instruments project sound by pushing air like a piston.
Tendens does not.
Its Active Soundboard behaves like a living acoustic surface, allowing complex wave behaviour to develop naturally — more like motion across a lake than a forced diaphragm. The result is an open, spatial sound that does not feel compressed or artificial, even in large halls or outdoor settings.
A Voice That Sings — and Speaks
Many modern concert grands favour immediate impact at the expense of sustain, turning musical lines into short-lived percussive events.
Tendens is built to sing.
It supports sustained, vocal phrasing while retaining the clarity and articulation required for fast and demanding repertoire. The instrument allows long musical lines without sacrificing precision or control.
Freedom from Inertia, Constraint, and Strain
By removing unnecessary mass and mechanical sluggishness, Tendens delivers an ultra-direct response with full authority. At the same time, it frees the pianist from the logistical, climatic, and maintenance burdens of immovable instruments.
Tendens can also be physically tailored — from keyboard geometry to action behaviour — allowing demanding repertoire to be played without the strain imposed by standardised concert grands.
This is not convenience as a compromise.
It is freedom as a consequence of better design.
A Serious Instrument for Serious Use
Tendens is built for pianists who require:
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uncompromised physical response,
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a sound that carries and sings,
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and an instrument that serves music rather than tradition for its own sake.
It is a concert piano rethought from first principles.
Active Sounboard Technology
The Active Soundboard is the system that allows Tendens to produce concert-scale acoustic sound without increasing mechanical inertia or delay.
In traditional pianos, sound projection is inseparable from physical size. Larger soundboards and longer strings increase mass and resistance, which inevitably reduces immediacy and control at the keyboard. Openness increases in larger halls, but responsiveness suffers.
Tendens removes this dependency.
By actively controlling the motion of the soundboard, acoustic output is no longer limited by the passive mechanics of the instrument. The soundboard behaves as a coherent acoustic surface that can be scaled without imposing additional load on the playing mechanism.
This allows Tendens to expand projection and tonal richness without compromising playability.
The keyboard and action remain fast and direct, while the sound maintains openness, clarity, and stability in large spaces.
The Active Soundboard is not a loudspeaker system, nor a simulation of an acoustic piano. It preserves the complex wave behaviour of a real soundboard, while eliminating the mechanical constraints that traditionally limit acoustic instruments.
Through this approach, Tendens achieves acoustic authority at scale without forcing the pianist to compensate for the instrument.
System Continuity
Tendens is conceived as a single instrument across multiple contexts, enabled through a deliberate system modularity.
Concert configurations and variants such as Tendens Pro Intimi share the same keyboard and action.
Through modular connection to the concert soundboard, the instrument can be used in compact configurations for daily work and extended seamlessly for performance, without changing the playing system.
This modularity is not about reconfiguration, but about continuity.
Technique, touch, and timing developed at home or in the studio transfer directly to the concert environment, without adaptation or recalibration.
System continuity is fundamental to Tendens:
one instrument, one response, one reference — independent of scale or setting.
This is what trying it does to you..
"Having played Horowitz’s Steinway, I know only too well how the magnificence of an instrument’s basic sound can inspire the artist to play way above his or her level. I had the same experience on the Tendens."
TENDENS ACCESS
Reference-Level Instrument Access Tendens is conceived as a continuously maintained concert instrument platform, not as a static object. For this reason, its primary mode of availability is Tendens Access. Tendens Access applies to the Tendens platform as a whole and is available across multiple configurations — from compact formats to full concert-scale instruments. Pricing and terms below are shown using Tendens Pro Concerto (2-panel) as a reference configuration. Access conditions and fees vary by configuration and scope. Under Tendens Access, the instrument remains Kaduk property and is maintained as a current reference implementation, receiving ongoing system and technology updates where applicable. Condition, calibration, and system state are actively controlled. If a component or subsystem no longer meets specification, it is serviced, replaced, or substituted to maintain uninterrupted professional use. This ensures that any Tendens instrument encountered represents the best state of the platform at that moment, not a preserved historical configuration. Long-Term Access (Reference Use) Long-term access is intended for institutions, venues, and artists who require guaranteed availability, stability, and uptime over an extended period. Included Dedicated use of a Tendens instrument in an agreed configuration (Pro Concerto shown as reference example) Continuous maintenance, calibration, and inspection Replacement of wear-critical components System and software updates and upgrades Reference-level condition guarantee Instrument readiness for international transport Right of substitution to ensure continuity of use Contract term Minimum commitment: 3 years Pricing (reference example: Pro Concerto, 2-panel) Access initiation fee: €30,000 Annual access fee: €20,000 per year Total over 3 years: €90,000 (excluding applicable taxes) This model replaces ownership with reference continuity and operational certainty. Concert Deployment (Short-Term Access) Tendens can also be deployed for short-term concert use, including festivals, touring productions, recordings, and special events. This option is intended for situations where: A reference-level instrument is required temporarily Transport, setup, and technical responsibility must be handled professionally No long-term commitment is desired Included Short-term deployment of a Tendens instrument in an agreed configuration Transport in professional flight cases On-site setup and calibration Technical readiness for performance Dedicated Kaduk technician present during use Continuous technical supervision throughout rehearsals and performances Instrument returned to reference condition after deployment Indicative pricing (reference example) Concert deployment: from €6,000 per week Transport, travel, and on-site technical support quoted separately, depending on location and scope Availability is limited and scheduled per project. Purchase (Stable Configuration) Alternatively, Tendens Pro Concerto can be acquired as a fully owned instrument in a defined, stable configuration. This option exists for contexts where permanent ownership is required. The purchased instrument represents a fixed reference version of Tendens at the time of delivery. Updates, reconfiguration, and long-term system evolution are not implicit and may require separate arrangements. Tendens Access programs are not offered through the webshop. Please contact us directly to discuss access, deployment, and availability. Purchase price (2-panel Pro Concerto): €140,000 (excluding applicable taxes)
