The Hampshire Electronics LADD is a warm, characterful 4-pole low-pass filter built around the legendary SSI2144 — the modern, low-noise successor to the classic SSM2044. Renowned for its smooth response, deep bass retention and musically pleasing resonance, the SSI2144 brings the unmistakable sound of vintage synth ladders into a compact, modern Eurorack module.

At the core of the LADD is the SSI2144’s precision-designed transconductance cell, providing a true 24 dB/octave low-pass slope, low distortion signal path and exceptionally controlled resonance behaviour. Unlike many ladder-style filters, the SSI2144 maintains excellent low-frequency amplitude even at higher resonance settings, avoiding the bass “thinning” common in older designs. The chip’s architecture also delivers an outstanding signal-to-noise ratio and superior dynamic range, making it equally suited to clean subtractive tones or aggressive, overdriven textures.

The LADD features a large, performance-friendly Frequency knob, voltage-controlled cutoff (CV input with attenuator), dedicated Resonance control, and three input jacks — audio input, CV input, and “Key” input for signal-level-dependent timbral shaping. The result is a flexible, musical filter ideal for bass, leads, pads, noise shaping, and tuned resonance effects.

Compact at 8HP, yet big in tone, the LADD channels the best of vintage ladder behaviour with the stability and fidelity of modern SSI engineering.

Please note that due to issues sourcing some knobs, the frequency knob may be substituted for a different but similar knob. 


Ladder VCF Manual: Download Ladder VCF Manual PDF

Specifications

General

• Format: Eurorack
• Width: 8HP
• Depth: 20 mm from faceplate (skiff-friendly)
• Circuitry: Fully analogue, SSI2144-based
• Filter Type: 4-pole (24 dB/oct) low-pass
• Slope: True ladder response with smooth roll-off
• Power Requirements:
  • +12 V: 15 mA
  • –12 V: 15 mA
• Faceplate: Durable composite or aluminium

Inputs / Outputs

• Audio Input
• CV Input (with attenuator)
• Key Input (for signal-level frequency modulation/compensation)
• Audio Output

Controls

• Frequency: Large primary cutoff knob
• Resonance: Musically tuned self-oscillation capable
• CV Attenuator: For precise modulation depth control

SSI2144 Performance Highlights

(derived from published datasheet characteristics)

• 24 dB/octave low-pass response
• Exceptionally low noise floor (improved over vintage SSM designs)
• High dynamic range and low distortion signal path
• Reduced low-frequency loss at high resonance
• Stable, voltage-controlled resonance capable of self-oscillation
• Classic “liquid” ladder character with modern precision and reliability