The Cochlea Concept

The loudspeaker design principle and the loudspeaker size interact with the listening space. Therefore, they are fundamental factors to be considered when developing solutions for music lovers and compact-living advocates.

The tension between compact size and “big” sound places high demands on the possible design solutions. The Cochlea Concept was developed precisely to strike a balance between the two.

A compact loudspeaker with controlled sound dispersion provides the best listening experience. These two factors together provide the uniform sound propagation over the entire frequency range and improve perceived audio characteristics of direction, distance, reflections, spaciousness, reverbs and transients of the sound at the listening position.

The Cochlea Concept™ also accommodates for the conflicting properties of low and high frequencies at reasonably low distortion. The name of the VoxTonus design concept stems from its resemblance to the human inner ear.



nano-Pi is the premium model in The Cochlea™ Concept Series, developed for the needs of the committed Music Enthusiast. Using innovative audio technology effectively to guarantee a small size, nano-Pi lives up to compact-living demands without compromising on sound quality.

The nano-Pi audio system includes two active loudspeakers, an exernal DSP system, and all cables necessary. As with all VoxTonus products, every nano-Pi loudspeaker is handcrafted and tested for quality assurance in the VoxTonus laboratory by Nils Hjelte.

The outside of the loudspeaker cabinet consists of side panels made of oak and our signature AluMatrix™ composite that covers the front, rear, top and bottom. The AluMatrix™ composite is folded around the Cochlea coil inside the cabinet, damped with a mix of materials to create an acoustically dead box.

A curved solid aluminum front is bolted onto the cabinet that holds the loudspeaker drivers in place. A laser-cut guard of stainless steel protects the loudspeaker drivers without influencing the magnetic field generated by Neodymium super magnet assembly. Applying our Cochlea Concept contributes to an extremely linear behavior and reduces distortions to a minimum.

Based on VoxTonus quality requirements, the amplifiers used are deliberately designed to be 10 times clearer (a THD value of less than 0.02%) than the signal the loudspeaker drivers are able to generate.

Quasi Non-Echoic Testing

Each loudspeaker driver is measured at 90dB SPL to pair those loudspeakers that are most similar to each other. The result is that each pair of loudspeakers only deviates from each other by less than 1.1dB over the entire frequency range.

After the final assembly, each nano-Pi loudspeaker is tested and measured in the VoxTonus quasi non-echoic chamber with calibrated equipment. Each pair of loudspeakers is delivered with a report detailing the unfiltered test results of the following properties:

  • Frequency range and phase at 90dB SPL, individually and paired
  • Step response
  • Total harmonic distortion (THD)
  • Directivity within +- 60 degrees horizontally in 5 degrees steps
  • Cumulative spectral decay

Next Level Material

AluMatrix™ is a composite consisting of two layers of aluminum that are connected by a Divinycell Matrix, which serves as vibration-damping core. This combination forms an extremely stiff and light composite (more than 6x stiffer and 30% lighter than MDF or plywood). AluMatrix™ reduces resonating noises commonly found in loudspeaker cabinets to a practically inaudible level and optimizes sound performance with its excellent thermal conductivity properties.

What’s included?

  • 2 individually paired nano-Pi loudspeakers
  • 1 DSP connection box (RCA input, mini-XLR output)
  • 2 double-shielded mini-XLR cables (3,5m)
  • 1 RCA cable (1,5m)
  • power supply adapter for the DSP
  • 1 IEC power connection cable (2m)
  • AC sockets with remote control
  • 1 individualized measurement report