Empress Effects Compressor Bass (Silver)

The Bass Compressor in Silver is a fully analog pedalboard compressor designed by Empress Effects specifically for bass players – with a feature set typical of high-end studio processors in a compact enclosure half the size of the original 2011 Empress Compressor. Standard controls (Ratio, Attack, Release, Mix, Input, Output) are joined by two elements unique to the bass version: a fully variable side-chain high-pass filter (20 Hz – 400 Hz) and a two-position Tone + Colour switch that adds gentle harmonic saturation and tonal shaping. A side-chain send/return via a 3.5 mm TRS jack enables external control of the detection circuit. Input impedance: 1 MΩ. Output impedance: 2.2 kΩ. THD: below 0.1%. SNR: –101 dB. Frequency response: 10 Hz – 20 kHz (–3 dB). Power: 9–18 V DC, 100 mA. Hand-built in Canada. Two-year warranty (four years on registration.

Side-chain HPF and Tone + Colour – two features without equivalent in standard compressors

The side-chain HPF (20 Hz – 400 Hz) excludes low frequencies from the compressor's detection circuit: set to 80–120 Hz, sub-bass and kick energy no longer trigger compression, and the compressor responds primarily to the mid and upper bass frequency range. The result is a full, non-pumping sound under dynamic control – a problem specific to electric bass and upright bass, where sub-bass energy routinely overdrives compressor detectors without such a filter. The 3.5 mm TRS send/return jack allows an external processor to be inserted into the side-chain path – typical use is removing a pedal tone from the detection signal of an electric bass, or triggering the compressor with a signal from another instrument. Tone + Colour in position 1 adds gentle harmonic distortion with a mid-range cut (warmer, denser character); position 2 provides an upper-mid boost (more presence and articulation). Both positions differ in coloration character – this is not a post-compression equalizer but deliberately added harmonic saturation that changes the tonal character of the compressed signal.

Metering, parallel mix and gain staging flexibility

Multi-segment LED indicators are split into two independent meters: Input (signal level entering the compressor) and Gain Reduction (compression depth) – allowing simultaneous assessment of the compressor's operating point without guessing from the Threshold knob. The Mix control implements parallel compression directly in the pedal: blending the dry and processed signals preserves transients and dynamics while adding the cohesion and density of the compressed signal. Ratio 2:1 is transparent dynamic control; 4:1 covers the standard recording range; 10:1 approaches limiting. Power supply compatibility across 9–18 V DC allows use with high-voltage power supplies, a useful flexibility in many pedalboard configurations.

KEY FEATURES

• Fully analog bass compressor with studio-grade controls, stompbox format
• Ratio: 2:1 / 4:1 / 10:1
• Independent Attack and Release controls
• Mix (Parallel Blend) – parallel compression in the pedal
• Side-chain HPF: variable 20 Hz – 400 Hz (excludes sub-bass from detection)
• Side-chain Send/Return: 3.5 mm TRS jack
• Tone + Colour: two-position, gentle harmonic saturation + tonal shaping
• Input and Gain Reduction metering (multi-segment LED)
• True bypass
• Power: 9–18 V DC, 100 mA
• Hand-built in Canada, 2/4-year warranty

TECHNICAL SPECIFICATIONS

• Type: fully analog bass compressor, stompbox
• Ratio: 2:1 / 4:1 / 10:1
• Attack: adjustable
• Release: adjustable
• Mix: Parallel Blend (dry/wet)
• Side-chain HPF: 20 Hz – 400 Hz (variable)
• Side-chain I/O: 3.5 mm TRS (send + return)
• Tone + Colour: 2 positions
• Input impedance: 1 MΩ
• Output impedance: 2.2 kΩ
• Frequency response (–3 dB): 10 Hz – 20 kHz
• THD: below 0.1%
• SNR: –101 dB
• Bypass: true bypass
• Power: 9–18 V DC, centre-negative, 2.1 mm, 100 mA
• Enclosure material: die-cast aluminium (Silver Sparkle finish)
• Dimensions: 122 × 66 × 38 mm (enclosure) / 122 × 66 × 64 mm (including controls)
• Weight: approx. 450 g