October 2024: Fractal Audio's VP4 Virtual Pedalboard has been added to the wiki.
Synth block
Contents
Available on which products
- Axe-Fx III: 2 blocks
- FM9: 1 block
- FM3: 1 block
- Axe-Fx II: 2 blocks
- AX8: 1 block
- FX8: 1 block
Channels or X/Y
- Axe-Fx III and FM9 and FM3: 2 channels
- Axe-Fx II: no
- AX8: no
- FX8: no
About the Synth block
"The Synth block is a very simple monophonic synth. It doesn't compare to the polyphonic capabilities of something like the FTP and it can't control outboard MIDI synths." [1]
"The lowest note detectable by the Synth block is 47 Hz. It is not intended for use with bass guitar." [2]
The Synth block requires monophonic input. It handles single notes only which means that you have to play REALLY clean and avoid overlapping notes. If you don't, you'll hear ugly "chirps".
"The chirping is due to the pick attack being interpreted as a high pitch. One approach I've tried is dynamic filtering (i.e. alpha-beta trackers, etc.) for the pitch but that introduces other problems with the pitch sliding between notes. It's a limitation of the technology. Real-time pitch detection is simply limited in what it can do. The best solution is to alter your technique to minimize pick attack." [3]
Look for synth presets created by Simeon, Swedish Chef, and Admin M@. Search the forum and visit Axe-Change.
Factory presets
The Synth block is showcased in a few factory presets. Search the Factory presets page for "synth".
Tips
Lower CPU usage
The Synth has 3 voices. Turn off voices that you don't use to save CPU.
Frequencies
The synth uses frequencies (Hz) instead of musical notes. Handy workaround: set the frequency to 440Hz and use the Shift control to alter the notes.
Test tone
If you want to make sure that the hardware is capable of generating sound, create a simple test tone:
- Add a Synth block and connect it to the grid output.
- Select the Sine waveform and turn off Tracking.
Warm up the Synth sound
To warm up / soften the sound of the synth, add a Drive block before or after it (try the RAT model).
Fatten the Synth sound
To fatten the Synth, use at least two voices and detune them slightly. [4]
Drone notes
- Turn off Voices 2 and 3.
- In voice 1 switch off Tracking and adjust pitch with the Frequency parameter.
Tips:
- Try the Sawtooth waveform.
- Make the sound fatter by using two Synth voices set to the same frequency.
- Make the sound less boring by adding a low-pass Filter with LFO-controlled Frequency.
- Make the sound wider by adding a 100% wet Multi-Delay or Plex Delay set to Detune.
- Change the pitch of the drone note, by switching the Synth between channels or by using Scene controllers, attached to the Pitch or Shift parameter of the voice(s). Or just send the Synth into a Pitch block (changes the pitch of all voices).
- Use the Sequencer controller to have the Synth block play lines.
Pink or white noise
The Synth block can generate white noise and pink noise.
Siren
Select a Square waveform and attach an LFO to the FREQ parameter of a single voice. Add a lot of reverb.
Calibration tone
"Set the synth block to a 1K sine wave at -12 dB. Turn OUTPUT 1 to the maximum level position." [5]
"There's actually a hidden calibration tone that is used during functional test. The Synth block is reference quality. I use it all the time to generate test tones. The output is spectrally purer than my $2000 Stanford Research Systems Synthesized Function Generator." [6]
"The Synth block is measurably better than our Stanford Research Systems generator (which cost $2000)." [7]