Ambifōn Boost

Description

The Ambifōn Boost is a very dynamic op-amp boost and drive combo circuit. It combines features inspired by the MXR Micro Amp, the Ibanez Tube Screamer, and the Nobels ODR-1. It is called "Ambifōn" because the pedal has two main voices: 1) a clean to light overdrive boost; 2) a heavier, dirtier boost configurable with different mids frequencies which is engaged by the DRIVE footswitch. Compression and texture is controlled by two sets of clipping diodes, one for soft clipping and one for hard clipping at the end of the circuit. This allows for light crunch to heavy distortion depending on the gain settings. Finally, the SWEEP knob lets the user go from a Marshall inspired mids emphasis sound, to a Fender Blackface inspired mids scooped sound.

• GAIN

  Controls the gain level for both the BOOST and DRIVE portions of the circuit. Goes from "Shine On You Crazy Diamond" Hiwatt cleans to a light natural breakup without DRIVE enabled. With DRIVE enabled, it gets heavier and dirtier and the user can configure what mids get pushed by selecting a frequency on the DRIVE FREQ rotary switch.

• BASS

  Passive bass control goes from ~15Hz to ~175Hz for custom low-end tightening.

• TREBLE

  The treble control simultaneously moves two poles of a bandpass filter from lower mids to high mids.

• SWEEP

  Highly original active tone shaping filter going from glassy cleans when all the way CW, neutral in the middle, to a dirtier lower mid emphasis when all the way CCW.

• SOFT

  Controls the texture and compression of the first gain stage. Setting this switch to less compressed will result in a lighter drive to pure boost depending on the GAIN setting.

• HARD

  Controls the texture and compression of the second gain stage. Setting this switch to less compressed will increase the headroom of the circuit overall.

• DRIVE FREQ

  Controls the frequency of the drive section of the circuit. This section is designed to work with whatever amp and guitar you have by offering various mid boost frequencies that compensate for what your rig may be lacking. For darker rigs, setting this feature to 1kHz will help you come through the mix. For lighter rigs, a 340Hz low mids push is what you need. 720Hz takes you to Tube Screamer territory but richer and fuller sounding in the Ambifōn Boost. Also adds more volume and clipping texture to the gain stage.

Input Z: ~450K
Output Z: ~25K
Gain:~+30dB (at max settings)
Current Draw: ~15mA

True Bypass
Requires a centre negative 9V power supply
Dimensions: 4.7 in x 3.7 in x 1.34 in
(119 mm x 94 mm x 34 mm)
No battery option. If user wants to use a battery, they must buy an external adaptor.