Femto

About the Femto

The Calyx Femto is a premium digital-to-analog converter from Calyx Audio, renowned for its exceptional soundstage precision, microdetail retrieval, and dynamic range. It employs dual ESS Technology ES9018 Sabre Reference DAC chips (one per channel), each with dedicated ultra-low jitter oscillators measuring 500 femtoseconds. The unit features a substantial linear power supply with separate transformers for digital and analog sections, housed in a shielded enclosure to minimize noise. Its all-aluminum chassis with cork-lined feet measures 430 x 102 x 403.8 mm and weighs 18.5 kg, emphasizing build quality and resonance control. Inputs include 2x coaxial RCA, 2x optical, 2x AES/EBU, 1x BNC, and 1x USB (asynchronous, up to 24-bit/192kHz), with both single-ended RCA and balanced XLR outputs. A digital volume control in 0.5 dB steps allows direct connection to power amps, and three selectable digital filters (50/60/70 kHz low-pass) are available. Reviewers praise its superior imaging, tonal balance with slight sweetness, solid bass, and airiness, outperforming predecessors like the 24/192. It remains a reference component, though as an older model (circa 2012), it may no longer be in active production.