detailed info

Funky-Fish Funk up your sound!

Detailed info - Advanced Filter Module and Basic Envelope Filter:


Both envelope filters share the same basic circuitry and have the same basic sound, that’s why we will discuss them together in this document. The “Basic Envelope Filter” pedal is made as a cost-effective solution to have that great MutronIII like sound in a small box (2 more adjustment trimmers are inside the pedal). The “Advanced Filter Module” at the other side is just the right tool for endless experimenting and exploring the possibilities of the that great funky sound. But bigger and more expensive than his smaller brother.


Conclusion, people who would like to experiment and that are always searching for new sounds, need the “Advanced Filter Module”. People who just want to get that great Mutron sound without extra features, just plug and play, will be more than happy with the “Basic Envelope Filter”.


Standard 9V DC supply and True Bypass.


Features on both pedals

  • SENS: sensitivity of the circuit to your input signal, adjust for your instrument and style of playing.
  • VOLUME: since envelope filters tend to add some volume to your signal, you can adjust your output volume with this potentiometer. (side note: inside the circuitry works on 18V, so you can get a lot of output volume. Pump that tube amp!)
  • DIRECTION: do you need a “wha” or a “ahw” effect?
  • RANGE: 2 ranges on the basic one, 3 range on the advanced module. Let you chose the tone range within which the filter will operate.
  • RESONANCE: (in the basic module implemented as a trimmer inside). Adjust the peaking, Q, resonance of your filter. Caution! All the way up will hurt your ears.
  • MIX: (in the basic module implemented as a trimmer inside). Since envelope filters can be rather extreme and let you lose some bass tones, it can be handy to add some original signal to your filtered signal.

Features only implemented in the “Advanced Filter Module”

  • FUNCTION: we wanted to get all possible possibilities out of this nice filter circuit and added some extra inputs. The pedal can operate in 3 modes, it means you have 3 possibilities for controlling your filter frequency:
    • ENV:
    standard, the pedal will just act as a regular envelope filter.
  • FOOT:
  • the pedal will be controlled by a pedal. You will have a wha-wha but with all the extra possibilities of this great filter module.
  • OSC:
  • this time the filter frequency is changed by an internal oscillator, so it acts like a vibrato or tremolo but again with a lot of possibilities to tune your sound.
    • FILTER: chose your filter type, low pass, high pass or band pass. The “Basic Envelope Filter” is always in low pass mode.
    • OSC SPEED: with this potentiometer you can adjust the speed of the internal oscillator when pedal operates in OSC mode.



    • 2 layers quality PCB’s with ground plane for maximum EMC performance.
    • Miniaturized design and easier/better PCB assembling/soldering by using SMD components.
    • No PCB jacks or footswitch is implemented since we know at the Funky-Fish repair center people tend to break this things no matter what the quality of the components is. By not putting them on the PCB and leaving enough space we allow an easy repair of this pedal if needed.
    • Like the MutronIII this pedal operates inside at + and -9V, this is one of the things that makes this unique sound. Still the pedal needs only a Boss style connected 9V DC supply. Inside the +9V is converted into -9V.
    • True Bypass.
    • In-house matched LED-LDR units.


    • Price for the “Basic Envelope Filter” is 170Euro and for the “Advance Filter Module” 250Euro (pedal included).
    • 2 years warranty.
    • Possibility of 2 weeks free trial of demo device. Demo device should be picked-up and returned by the costumer.






    Extra Info

    Family picture with the older brothers (version1 and version2) and matching of the LDR-LED units