Resonator – Otherworldly ‘Wah’ Filter Sweeps

[brock]

Need a classic CryBaby or Clyde McCoy wah sound?  This isn’t it.

The sound from this kind of preset is difficult to pin down.  There are elements of stepped filters, vocal formants, thru-0 flange cancellations, micro-delays … a watery, unique, synth-like wah under foot control.  It’s easy enough to program:  Gang all 4 Note parameters to sweep together with an expression pedal.  (There’s also something to be said for offsetting the sync among “notes”.)

Expression Pedal Heel Position

Expression Pedal Heel  NOTE 1  C3

Expression Pedal Heel  NOTE 2  C3 

Expression Pedal Heel  NOTE 3  C3 

Expression Pedal Heel  NOTE 4  C3 

 

Expression Pedal Toe Position

Expression Pedal Toe   NOTE 1  B5

Expression Pedal Toe   NOTE 2  B5 

Expression Pedal Toe   NOTE 3  B5 

Expression Pedal Toe   NOTE 4  B5  

Carefully adjust RESONANCE and MIX together to fine-tune the vocal quality and depth of synthetic effect.  I mixed this preset fairly high for demonstration purposes.  But with rapid sweeping of the pedal, you can try dialing down to a 50:50 MIX.  That especially helps with automatic EXP PED sweeping; using a Source Audio Reflex (or HotHand), EHX 8 Step Program, DAW sequencer, or similar.  Control by a virtual ‘LFO shape’ creates some uncommon super-flanger effects.

 

The LENGTH parameter here clusters the 4-note spacing inside 0 milliseconds.  Quantum physics aside, as you increase the LENGTH to – say, several hundred milliseconds – the expression pedal sweeps take on a staggered, multi-sweep characteristic.  That will continue to deepen the filter sweep effect until discrete echoes begin to emerge.

For the HotSwitch programming, I set up a more ‘normal’ Resonator configuration.  The difference here is that the expression pedal filter sweeps are imprinted on the individual delays.  Whatever frequencies are being swept at the moment are repeated throughout the FEEDBACK cycle.  Parked pedal positions become a foot-controlled mix over darker and brighter delays (that overlap in the regeneration path).

HotSwitch ON Position [Expression Pedal at Mid-Travel]  

HotSwitch OFF  MIX  75

HotSwitch OFF  LENGTH  0 mS

HotSwitch OFF  FEEDBACK  FB1:  0

HotSwitch OFF  RESONANCE  (-) 4

HotSwitch ON   MIX  50

HotSwitch ON   LENGTH  1000 mS

HotSwitch ON   FEEDBACK  FB1:  25

HotSwitch ON   RESONANCE  10

[KCStratman]

Very cool, Brock thanks again for more great ideas and presets!

[brock]

Forgive the necro-bump for a quick update.  I tweaked the preset above to have a Resonance value of 0.  The idea was to create stacked, ‘semi-parametric EQ’ to tune in frequency ranges, in a more subtle sense.  It certainly achieves that, but with a twist.

Rapid expression pedal movement actually ‘bends pitch’.  Only the frequency spectrum carving is apparent at parked positions (no pitch shift).  I assume the pitch bending phenomenon is due to allpass filter modulation, when mixed with some dry signal.

Cool, unexpected stuff.

[Author]

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