H2 Audio 2128

H2 Audio 2128 moves the microphone preamp from the Helios 0011 module into 500 series format. The Lustraphone M10 input transformer is retained, with an added output stage carrying its own transformer and level control.

Helios in the 500 rack you already own

Buying into the 0011 system means committing to a dedicated rack and power supply. The 2128 runs in any standard 500 series chassis on 16 V rails, so the same input circuit enters the studio without rebuilding the rig. Paired with the 5011 equalizer it reconstructs the complete 0011 Type 69 module.

Level control at two points in the path

Microphone gain runs from 25 to 75 dB on a stepped switch with 5 dB detents, while a separate output control adds up to 10 dB. That lets you drive the input stage hard for transformer saturation and then pull level back at the output, rather than choosing between clean and characterful. A 20 dB pad, phase switch, phantom power and a 0/40/80 Hz filter sit on the front panel.

KEY FEATURES

• Helios 0011 preamp circuit in 500 series format
• Lustraphone M10 input transformer contributing 20 dB of gain
• 25-75 dB of gain in 5 dB steps with a 20 dB pad
• Transformer-balanced output stage with up to 10 dB of additional control
• High-pass filter at 0, 40 or 80 Hz
• Phase inversion and phantom power
• Gold-plated ELMA switches, hand-assembled in Detroit

TECHNICAL SPECIFICATIONS

• Format: 500 series module, single slot
• Microphone gain: 25-75 dB in 5 dB steps
• Input transformer: Lustraphone M10, 20 dB of gain
• Input pad: -20 dB
• Output control: up to +10 dB
• High-pass filter: 0 Hz, 40 Hz, 80 Hz
• Output: transformer balanced, 600 ohm drive
• Maximum output: 25 dBm before clipping
• Power: +/- 16 V from the 500 series rack
• Dimensions: 5.25" x 1.5" (3U)