TC Electronic SUB 'N' UP OCTAVER Next-Generation Polyphonic Octave Pedal with Monophonic Octaver and Built-In TonePrint Technology, Compatible with PC and Mac : Amazon.co.uk: Musical Instruments & DJ
Best octave pedal for electric cello: Electro Harmonix Micro POG vs. tc electronic Sub 'n' Up | The Wong Janice - Ambient Cello Meditation Music
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simple octave up pedal for bass : r/diypedals
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