Electro-Harmonix MAINFRAME Bit Crusher - Sample Rate Reducer

Buzz. Beep and bloop. We’re high on the lo-fi sounds of “old-school” games, toys and terminals and the Mainframe Bit Crusher takes us back in time to when Pac Man and Donkey Kong ruled the arcades, to when the Commodore 64 was high tech.

It provides sample rate reduction ranging from 48kHz to 110Hz. A little background… the sample rate is the number of times per second that a sample or snapshot of an analog signal is taken. For example, CDs (remember them?) had a sample rate of 44.1kHz which means that the original analog signal is sampled 44,100 times per second.

 

• Sample Rate Reduction ranging from 48kHz to 110Hz
• Bit Depth Reduction ranging from 24-bit to 1-bit
• Selectable High/Low/Band-Pass filter to shape the artifacts of the bit crushing and sample rate reduction
• Sample Rate Tuning Mode allows you to set the sample rate to match the key of a song, or continually adjust the sample rate based on what you play on your instrument
• Programmable preset or expression pedal setting allows you to save your sound or control any combination of the Mainframe’s knobs with an external expression pedal
• Secondary knob parameters allow you to fine-tune the Mainframe’s effect
• High quality buffered bypass and silent switching
• Comes equipped with an Electro-Harmonix 9.6DC-200mA PSU
• 13. 9V Power Jack Plug the output of the Mainframe’s supplied EHX9.6DC 200mA AC adapter to the 9V power jack located at the top of the pedal. The Mainframe requires 90mA at 9VDC with a center-negative plug. Do not exceed 10.5VDC on the power jack.

• VOL Knob This knob sets the master output level of the Mainframe.
• BLEND Knob This knob blends between the dry guitar signal and the effect signal. As the knob is turned clockwise, the output ranges from completely dry guitar to a fully effected signal with the filter applied.
  
• BIT DEPTH Knob As this knob is turned clockwise, the bit depth of the signal is reduced, producing a distorted, noisy tone.
  
• SAMPLE RATE Knob As this knob is turned clockwise, the sample rate of the signal is reduced, producing a ringing or glitchy tone.
  
• FILTER HPF/BPF/LPF Switch This toggle switch controls the direction of the Mainframe’s filter
  
• HPF: High-Pass Filter
• BPF: Band-Pass Filter
• LPF: Low-Pass Filter
• FILTER FREQ This knob controls the frequency of the Mainframe’s filter. As the knob is turned up, the frequency increases. The frequencies cut/passed by the filter vary by the filter type
  
• HPF: Frequencies above the FREQ knob setting are passed, frequencies below are cut.
• BPF: The FREQ knob controls the center frequency of a pass band. Frequencies above and below this center frequency are cut.
• LPF: Frequencies below the FREQ knob setting are passed, frequencies above are cut.
• Tip: For a tone with no filtering, set the FREQ knob to maximum and set the toggle switch to LPF.
• FILTER PEAK This knob controls the resonance of the Mainframe’s filter. Turning this knob clockwise increases the resonance, producing a sharper, more cutting tone.
  
• EXP / PRESET Button and Green LED This button turns expression mode or a saved preset on and off. When the Green LED is lit, expression control is enabled, or the preset is enabled. See pages 6-9 for details on how to save expression settings or a preset.
  
• Footswitch and Red LED Press and release the footswitch to toggle between bypass and effect modes. When the red LED is lit, the Mainframe is in effect mode. Double tap the footswitch to enter Sample Rate Tuning Mode, and tap it once again to exit Sample Rate Tuning Mode and save the tuned sample rate.
  
• INPUT Jack This 1/4" phone jack is the audio input of the Mainframe. The input impedance is 2MΩ.
  
• OUTPUT Jack This 1/4" phone jack is the main audio output of the Mainframe. The output impedance is 500Ω.
  
• EXP Jack Connect an expression pedal or control voltage jack to allow for external control over every knob on the Mainframe. See pages 6-9 for a description on how to set up and control the Mainframe with an external expression pedal.