Floorstanding loudspeakers — Avalon Accoustics Tesseract

The Tesseract is a system of the Avalon Acoustics Signature series, which the Colorado maker presents as the culmination of more than 30 years of research into music waveforms and psychoacoustic perception. Avalon also names it the Tesseract Signature. Each channel is formed by two independent cabinets stacked vertically, and the lower section contains its own amplification for the bass, so the system is partly active while the upper range stays passive.

Key specs that matter

Every channel carries seven drivers. Four 15 inch low Q, high force factor subwoofers work in the lower enclosure, while the upper enclosure holds an 11 inch midbass with a ceramic and honeycomb cone, a 4.5 inch ceramic midrange and a 0.78 inch diamond tweeter, all three with underhung voice coils. Avalon quotes 16 Hz to 100 kHz within 0.5 dB anechoic and 1 dB typical in a room, an efficiency of 93.5 dB at 1 W and 1 m, and harmonic distortion of 0.30% across the band. Nominal impedance is 6 ohm with a minimum of 4 ohm at 80 Hz, while Avalon suggests between 15 and 500 W of amplifier power. Overall height is 221 cm, width 74 cm and depth 82 cm. One channel weighs 375 kg, a pair 750 kg, and the shipping weight reaches 908 kg.

Engineering and use context

The four subwoofers are arranged as an internally powered isobaric transmission line, a quad driver system with 4.5 kilowatts of peak power per channel and tempered-scale aperiodic tuning. Its circuitry is fully analogue and symmetrical, with no digital conversion or processing anywhere in the signal path. A toggle switch selects the low-frequency contour, trading maximum extension against transient speed, and a master gain control moves the bass level by 2.5 dB either way in fixed 0.25 dB steps. Cabinets use Silent Inert Composite construction, and the passive section relies on phase linear filter topologies designed to present a fully damped, non-reactive load to the amplifier. Avalon groups the radiation control work under the name Stealth Technology, which targets the launch surface and energy returning from the room.

Pairing

Because the bass is driven by its own built-in amplifiers, the external amplifier only has to feed the upper cabinet, which explains the low minimum power. A valve or solid-state amplifier of moderate size is enough. Each lower cabinet needs mains power, and the total mass requires a floor assessment and specialist delivery before installation.

Alternatives

The Avalon Saga Signature is the passive floorstanding model in the same Signature series, using a single cabinet with two 13 inch woofers per side.