H2 Audio Helios Channel Mic Preamp/EQ/Compressor

Built as a complete Helios-inspired recording channel in a single 2U rackmount unit, the H2 Audio Helios Channel Mic Preamp/EQ/Compressor combines three stages of classic analog processing for tracking and mixing. Its mic preamp recreates the renowned Helios 2128 circuit, pairing 25–75dB of stepped gain with a Lustraphone M10 input transformer and original-style Helios output amplifier and transformer. An inductor-based 3-band EQ provides extensive low- and mid-frequency shaping alongside a fixed 10kHz high-frequency band, while the integrated H760 FET compressor/limiter adds selectable ratio, attack and release settings for dynamic control. A transformer-coupled DI based on the Acme Audio Motown circuit expands the Helios Channel beyond microphones, giving engineers a versatile analog front end for vocals, instruments and other studio sources.

Helios 2128 Preamp and Inductor-Based EQ

At the front of the signal path, the Helios Channel recreates the 2128 mic preamp circuit with 25–75dB of gain selectable in 5dB increments. The Lustraphone M10 input transformer supplies 20dB of gain before the preamp, while a Helios-designed output amplifier and transformer provide the output stage. For tone shaping, the inductor-based EQ offers selectable low- and mid-frequency controls plus fixed 10kHz high-frequency adjustment. Low-frequency boost points at 60, 100, 200 and 300Hz combine with variable or 50Hz filtering, while eight selectable midrange frequencies extend from 0.7–6kHz. EQ bypass, phase control and selectable 40 or 80Hz high-pass filtering provide additional flexibility when shaping a source.

H760 FET Compression and Flexible Analog Routing

The integrated H760 compressor/limiter brings another important Helios circuit into the channel, drawing on the AD&R-designed FET compressor/limiter historically fitted to Helios consoles. Its fixed-threshold design provides selectable ratios plus adjustable attack and release settings, with a separate limiter threshold for additional dynamic control. Beyond its integrated channel-strip workflow, the Helios Channel provides separate I/O for the 0011 preamp/EQ and H760 compressor/limiter sections, allowing them to be incorporated independently into a studio signal chain. A transformer-coupled DI based on the Acme Audio Motown circuit connects directly to the mic input, adding a dedicated path for instruments while retaining the unit's transformer-based analog architecture.

Classic Helios Processing in a Complete Studio Channel

From initial gain and tonal shaping to compression and limiting, the Helios Channel places a substantial range of analog processing within one 19" rackmount unit. Its combination of transformer-based 2128-style amplification, inductor EQ, H760 FET dynamics and transformer-coupled DI makes it suited to engineers who want a unified recording front end while retaining the flexibility to access individual processing stages. Hand-assembled in Detroit with custom transformers and a 100% analog signal path, the H2 Audio Helios Channel Mic Preamp/EQ/Compressor brings multiple elements of the classic Helios recording architecture together for modern tracking and mixing workflows.