Designed to fulfill unique high-end requirements…

FEMTO is the natural extension of our product range, offering superior directivity and integration in reverberant rooms. This loudspeaker preserves the signature qualities of our products: exceptional sound stage, precision, and resonance-free reproduction. When used with our 3960 DSP and TERA subwoofer, it delivers high-end performance comparable to large column loudspeakers, with optimized low-frequency transducer placement.

FEMTO is available as a biamp system only, ideally paired with 2 x TERA. Its cabinet, milled from a solid block of aluminum, ensures minimal resonance. Designed to last a lifetime, FEMTO is entirely crafted by Lange Loudspeakers SA in Switzerland, including the drive units.

Suggested end user price; 4'640.- CHF per unit

Technical features

Two-Way 80 Hz to 28 kHz frequency range

Anti-Resonance Full Aluminum CNC-Machined Enclosure

Aluminum Diaphragm, optimized geometry that achieves metamaterial performance

Custom designed high frequency driver

Coherent Coverage on Stated Frequency Response

Offers 70°H x 50°V directivity control over an important part of the spectrum

Suitable applications

High-End Home Entertainment

Studio Monitoring 

Home Cinema – THX/Dolby Atmos

Technical Description

Configuration 2-Way Sealed Box System

Recommended amplifier power 50W – 200W into 8Ω on unclipped program.

Net weight 19,4 kg 

Dimensions 254 mm depth, 195 mm width, 270 mm height

Finishes Finely sand-blasted, black anodized or RAL painted.

Drive units 1x Lange 1705-4A LMF Driver / 1 x Lange 1425-8A HF Driver

Frequency range 80Hz to 28kHz

Frequency response 100 Hz to 28kHz (+/-2,5 dB from reference axis)

Sensitivity 89 dB (on axis at 2.00Vrms at 1m)

Harmonic distortion 

2nd and 3rd harmonics (1W-1mt) <0.7% 100Hz – 20kHz

Complimentary Products  Lange Loudspeakers TERA Active Subwoofer

Designed and built by Lange Loudspeakers SA

This exceptional compression driver offers an extended frequency response ranging from 1200 Hz up to 28 kHz. Featuring an ultra-light magnesium dome, it is equipped with a 3-channel circumferential phase plug specifically designed for our systems. With a magnetic induction of 15000 gauss and a 0.5 mm Xmax, it delivers high efficiency, low distortion, and an extended frequency range. The relatively large horn of the FEMTO enhances a controlled coverage, even at frequencies beyond the human hearing threshold.

A masterpiece of engineering

Imagine a speaker meticulously carved from a single block of 6030 aluminum, seamlessly integrating a horn into its geometry. This is FEMTO - a masterpiece of engineering and craftsmanship, where every detail is sculpted to perfection.

Critical parts designed internally

The newly designed 1705-XA & 4A integrated in our ATTO & DECA shares all key elements also with the FEMTO System and represents a significant upgrade in all aspects. It features a modern voice coil with a two-layer copper-clad aluminum wire, an upgraded and highly efficient slug type magnet with N52 grade neodymium, a redesigned one-piece oxidized aluminum diaphragm with transitional geometry, and a nitrile suspension. These enhancements are aimed at boosting overall performance and significantly reducing variations in loudspeaker driver performance compared to drivers based on paper cone/dust cup with cloth suspension.