CG Products
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Eurorack Module


Dynamic Percussion Interface

The Peak & Hold allows one to play and control analog synthesizer equipment using a drum with a pickup or any other percussive signal source. It generates 9 different CV/signal outputs from one input source. The Peak+Hold provides a dynamic hold voltage (linear and logarithmic), a dynamic impulse signal e.g. for triggering filters or delays, a dynamic release signal (linear and logarithmic), an envelope and a gate signal output. Additionally, the original sound signal (amplified) is available for further signal processing. The input stage is equipped with adjustable level and trigger controls and a filter for flexible adaptation of different percussive instruments – such as long or short sounding, high or low drums and cymbals. Furthermore, there is a 2nd input to cascade two Peak+Holds or to add another signal source. Without pickup, the Peak+Hold can be used for creating additional CVs and triggers from any percussive input signal (e.g. from a drum machine or an audio player).
Peak+Hold front view
Minijack version
  • Dynamic signal processing
  • 9 different CV/signal outputs
  • Manual level, trigger and filter controls of the input signal
  • Selectable frequency band (for cascading 2 or more P+Hs)
  • Pickup included
  • Optional with banana or 3,5mm minijack sockets
  • Width: 10 HP
  • Dimensions: 128,5 mm x 50,5 mm
  • Depth: 35mm
  • Supply voltage: ±12V
  • Consumption: max.75mA


XR22VCO, 2 X multipliers, Noise
Delay1022 with KorgMS20 filters & VCA
2 P+Hs in frequency-selective mode; 2 XR22VCOs, Delay1022, KorgMS20
Input: Cymbal; 2 XR22VCOs, Delay1022, KorgMS20
Input: Rhythm machine; XR22VCO, Delay1022
Or listen on  

PDF Download

P+H PDF documentation
Peak+Hold panel drawing
Peak+Hold right side view
Side view right
Peak+Hold left side view
Side view left
Peak+Hold side view left 90°
Side view left 90°
P+H Pickup

YouTube video

Principle of Operation

Similar to a ‚Sample & Hold‘, the Peak+Hold detects an input signal’s amplitude when triggered and keeps it as hold voltage until the next trigger appears. But in contrast to the S&H, which keeps the signal amplitude’s momentary level, the P+H holds its highest amplitude level (peak). The following incoming signal resets the Peak+Hold by triggering at the very beginning and the next hold value will be set. The trigger threshold is adjustable by knob ‚Trigger‘. In addition,there is a ‚Filter‘ knob allowing to adapt the P+H to various input signal sources, such as drums or cymbals. This special lowpass filter is only affecting the falling edges of the internal envelope signal, ensuring minimal latency and best response to all percussive input sounds. ‚Impulse Out‘ and ‚Release Out‘ have a slightly different operation principle: After triggering by an input signal, a minimal latency time is internally set. At the end of this time, the momentary volume amplitude value is detected and generates now the hold voltage on the outputs ‚Impulse Out‘ and ‚Release Out‘. Duration of the impulse signal can be regulated by knob ‚Impulse‘, length of the release time by knob ‚Release‘.

Examples of typical output waveforms

Pickup settings

There is a piezo pickup and double-sided adhesive tape included to the Peak+Hold module package by standard, so it is easy to connect the P+H to any percussive instrument. The pickup is equipped with 1/4′ jack and 2m cable.

Pickup on tabletop Pickup on wooden board Pickup on wooden board II Pickup on bongo drum Pickup on cymbal
Tabletop Wooden board Bongo drum Cymbal


Simple patches with other (CG Products‘) modules

Patch Description Audio

1. Peak+Hold controlling the XR22 VCO FT The Peak+Hold’s linear release output is connected to the XR22VCO FT’s AM input and controls the VCO’s sinewave/triangle output amplitude.

Different XR22VCO frequency settings …Peak+Hold CV outs are controlling the VCO’s frequencies (in FSK mode)


2. Peak+Hold triggering the Delay1022 The dynamic pulse output of the Peak+Hold triggering the Delay1022 is a simple way to create percussive drum- and string-like sounds. Instead of a delay, also VCFs with high resonance can be triggered.

Different Delay1022 Lowpass filter settings …Peak+Hold CV output is controlling the delay time


3. Peak+Hold and X multipliers The Peak+Hold ’s logarithmic release output is connected to the control inputs of 2 X multipliers. The multipliers are working as exponential VCAs with different operation points (see different positions of knobs ‚Offset‘ and ‚Level‘). The 2nd X multiplier only gets active from a certain CV amplitude level.

1st X audio signal in: VCO 2nd X audio signal in: Noise/VCO; Peak+Hold Input: Pickup on drum …Rhythm machine


4. Peak+Hold with Pre When running the Peak+Hold with the Pre (The preamplifier’s output is applied on ‚In 2‘ ), the Pre’s knob ‚Sensitivity‘ is overtaking the function of the Peak+Hold knob ‚Input1 Level‘ (which is only referring to input socket ‚Drum In‘).

Pre Microphone input: Different percussion instruments. Peak+Hold CV outs are controlling cutoff frequencies of Korg MS20 VCFs and VCA envelope