PunkFX

This is the documentation page for PunkFX. I still have to document the whole thing but you can expect to see the insights of each plugin.

Training LSTM models for accurate tone capture

I started using Machine Learning to capture my pedals thanks to GuitarML videos on YouTube, huge props to that man!

Long story short, I have a Google Collab notebook where I upload audios of a clean input signal and the processed output with the drive knob of the pedal at different settings; tone knobs are set at the most neutral settings since they can be easily emulated with digital filters.

My notebook looks something like the block below; be aware that the Parameterization-Config.json as well as the input arguments for the training instruction may be different for each case:

# Environment setup
!git clone https://github.com/GuitarML/Automated-GuitarAmpModelling.git

cd Automated-GuitarAmpModelling/

!git submodule update --init --recursive

# Paramteterized Model
!python prep_wav.py "LPB1_Parameterized" -p "./Configs/Parameterization-Config.json"

!python dist_model_recnet.py -l RNN3-LPB1_Parameterized -eps 200 -lr 0.0005 -is 2 -hs 32

PunkKomp

PunkKomp is a regular compressor implemented with JUCE's built-in compressor class. In order to emulate the behaviour of the Suhr Koji Compressor pedal, it also has a Voice switch which applies a boost in the high frequencies after the compressor.



PunkBoost

PunkBoost is a booster based on parallel compressor and overdrive implemented with JUCE's built-in components. The signal path is the following:

1. Pre-Equalization:
   • Bass: ±12dB at 80Hz.
   • Mids: ±12dB at selected frequency.
   • Highs: ±12dB at 5kHz.
2. Boost. ±12dB of gain that feed a parallel exciter processor. The exciter is simply a saturation processor made with compressors and waveshapers that are blended with the clean signal to generate some harmonics.
3. Character. An equalizer controlled with a single knob inspired in the VPF control on Markbass amplifiers. At minimum, the eq curve is flat; at maximum, the eq curve boosts lows and highs and dips the mids (around 500Hz). It kinda acts like a cab IR.



PunkDist

• The Drive controls the gain that feeds an LSTM model trained with a Markbass Minidist pedal.
• Tone 1: Selects the frequency (from 200 up to 2500 Hz) at which a small boost is applied. The boost amount also increases with the frequency, in fact, no boost is applied when the knob is at its minimum.
• Tone 2: Dips the signal (from 0 down to -20 dB) at 800 Hz. It also applies a little bump at 80 Hz.


PunkMuff

• The Sustain controls the gain that feeds an LSTM model trained with a EHX Big Muff Pi pedal.
• Tone & Mode: Adjust the frequency response after the clipping. The MODE emulates the EQ curves of the following pedals:
  • Mode 1: Big Muff Pi.
  • Mode 2: Elk Sustainer.
  • Mode 3: Custom modification.
• Level: Adjust the output gain.


PunkXros

• The Drive controls the gain that feeds an LSTM model trained with a Darkglass B7k pedal.
• Low frequencies processing:
  • Low pass: Selects the cutoff frequency (between 50-500Hz) at which a low-pass filter is applied.
  • The Level control increases the input gain of a compressor that is only applied to this band.
• High frequencies processing: ±12dB of gain that feed a parallel exciter processor.
  • High pass: Selects the cutoff frequency (between 100-1000Hz) at which a high-pass filter is applied.
  • The Level control increases the input gain of a distortion that is only applied to this band.
• Mix: Blends the low and high frequencies bands.
• Mids: ±12dB at 500Hz applied after the previous processing.