The Demeter HXC-1 Compressor is a mono, rack-mount tube compressor from Demeter Amplification. Demeter describes it as combining the company's H tube preamplifier with a classic photocell compressor, and says the result is "the sound of a classic tube optical compressor without the noise and low fidelity sound often associated with them"1. It is a single-channel unit aimed at the studio and stage rack rather than a pedalboard, and it is listed under Pro Audio on the maker's site1.
Release, gain and compression ranges
The HXC-1 gives the player control over the parameters that shape a compressor's behavior, and the ranges are wide enough to cover gentle leveling through to heavy squeezing1:
- Compression: over 24 dB of compression control1
- Release: variable from 100 milliseconds to 3 seconds1
- Gain: variable from 20 dB to 30 dB1
The release range runs from a quick 100 milliseconds, which keeps things dense, up to 3 seconds for a slow, smooth breathing motion. The 20 to 30 dB of variable gain lets you make up the level the compression takes away1.
Connections and specifications
The unit is built around balanced connections on both sides of the circuit, with XLR and TRS 1/4-inch jacks for inputs and outputs1.
| Specification | Value |
|---|---|
| Inputs | XLR, TRS 1/4-inch1 |
| Outputs | XLR, TRS 1/4-inch1 |
| Input impedance | Balanced 10k ohms1 |
| Output impedance | Balanced +28 into 600 ohms1 |
| Frequency response | 20 Hz to 20 kHz, + or - 0.1 dB1 |
| Signal to noise | -95 dB EIN1 |
| Operating voltage | 230/115V AC1 |
| Weight | 15 lbs1 |
The HXC-1 runs on mains power at 230/115V AC, not a DC pedal supply, and at 15 lbs it is a rack unit rather than something to carry on a pedalboard1.
How it works and what it is for
Demeter describes the HXC-1 as "a mono tube compressor utilizing the revolutionary H tube preamplifier with a classic photo cell compressor"1. A photocell compressor is the optical design behind vintage studio levelers: a light-sensitive element reacts to the signal and controls the gain, which is a way of compressing that players have long associated with a smooth, musical character. Demeter pairs that circuit with a tube preamp stage and adds an input sensitivity switch to match the unit to the source feeding it1.
The maker's own description of the sound is clean and classic: "Now you can have the sound of a classic tube optical compressor without the noise and low fidelity sound often associated with them"1. In other words, the goal is the character of an old tube optical design with the measured performance of a modern unit, and the specifications above, such as the 20 Hz to 20 kHz response within 0.1 dB and the -95 dB EIN signal-to-noise figure, are what Demeter publishes in support of that1.
Questions
Is the Demeter HXC-1 a tube or solid-state compressor?
It is a tube compressor. Demeter describes the HXC-1 as a mono tube compressor that uses the company's H tube preamplifier together with a classic photocell compressor circuit. The unit runs on 12AX7a selected tubes, and Demeter positions it as delivering the sound of a classic tube optical compressor without the noise and low fidelity often associated with older designs.
What tube does the Demeter HXC-1 use?
The HXC-1 uses 12AX7a selected tubes, according to Demeter's product page. The 12AX7 is a common dual-triode preamp tube, and the selected designation indicates the tubes are chosen for the unit. The tube stage is part of the H tube preamplifier that Demeter pairs with the photocell compressor circuit in the HXC-1.
Does the Demeter HXC-1 have XLR connections?
Yes. The HXC-1 has both XLR and TRS 1/4-inch connections on its inputs and its outputs, so it can be patched into balanced studio lines or with 1/4-inch TRS cables. The unit also carries an input sensitivity switch, which lets the input stage be matched to the level of the source feeding it.
How much does the Demeter HXC-1 weigh?
Demeter lists the HXC-1 at 15 lbs, with dimensions of 24 x 16 x 10 inches. Those figures describe a rack unit rather than a pedal, so plan rack space and carrying accordingly if you intend to move it between rehearsal, studio or stage.
Can the Demeter HXC-1 be used with guitar or bass?
The HXC-1 is a mono compressor with 1/4-inch TRS and XLR inputs and an input sensitivity switch for matching different source levels, so it can accept an instrument or line signal on a single channel. Demeter lists it under Pro Audio rather than as a guitar pedal, and it is a rack unit, not a stompbox.
Sources (1)
- HXC-1 Compressor, Demeter Amplification