So as I've been learning some about synth pedals, I've quickly realized how many there are and how many different features each one does/does not have. For both my own benefit and anyone else who comes after me, I figured I'd put together a quick list of some of the ones I've found and some of their defining features. By all means, please join in and correct me if necessary, add info, etc., and maybe this can become a useful beginner's guide or point in the right direction for someone looking into the world of synth... After all, as different as they all are, and considering most Guitar Centers don't stock anywhere near most (or even many) of them, the sheer number of what's out there can be kinda daunting at first...
EHX Bass Micro Synth
Monophonic
Sub-octave (-1)
Octave (+1)
Square wave/distortion
Filter
Attack delay
Layering of octaves
EHX HOG
Polyphonic
Sub-octave (-2 and -1)
Octave (+1, +2, +3 and +4)
Harmonics (+5th, +1+5th and +2+3rd)
Envelope filter
Expressions modes
Expression pedal
Layering of octaves
EHX POG
Polyphonic
Sub-octave (-1)
Octave (+1 and +2)
Layering of octaves
EHX Micro POG
Polyphonic
Sub-octave (-1)
Octave (+1)
Layering of octaves
Pigtronix Mothership
Monophonic
Sub-octave (-1)
Square wave or triangle wave (anywhere between -2 and +2)
Intelligent ring modulator
Whammy
Chunk Systems Octavius Squeezer
Sub-octave (-1 and -2)
Octave (+1 and +2, also +5th)
Square, triangle, sawtooth or trapezoid wave
Variable duty on square wave and variable slope on sawtooth wave
Filter (envelope or ADSR)
Fuzz (w/ gate)
LFO and beat-locked effects
Programmable
MI Audio Pollyanna Octave
Sub-octave (-2 and -1)
Octave (+1)
Square wave on sub-octaves
"Fuzz"
"Interactive" sensitivity control (best quick way I could think of to describe it)
Layering of octaves
Korg G5
Sawtooth (same pitch or octave down)
Sawtooth (same pitch) plus Square (octave down)
"Fuzz" voices
Formant Filter-like voices
Envelope or expression-controlled low-pass filter.
9 memory locations
Moog Freqbox
Waveforms: Triangle, Square, Up Sawtooth, Pulse
Hard Sync on/off of oscillator
Freq of osc.
Envelope (controlling Freq of osc.)
FM Amount
Clean blend
All knobs controllable by CV
Robot Factory Pulse Synth
Square/Pulse wave (variable duty)
LFO modulation of duty cycle
Envelope control over LFO speed
So those are the first few that immediately come to mind. Feel free to mention some others or add some info to what I've already posted. Again, this is just intended to be a kind of one-stop shop for those new to synth effects to give them a quick glimpse at what can do what. Thanks!
Brian