api TranZformer CMP Compressor Pedal User Guide
- June 5, 2024
- API
Table of Contents
api TranZformer CMP Compressor Pedal User Guide
Introduction
The API Select TranZformer CMP provides unsurpassed sonic sculpting by incorporating key elements of the legendary API 527 VCA-type compressor circuit into a versatile and robust guitar effects pedal.
Features include adjustable attack and release times, wet/dry blend control, selectable “feedback” and “feedforward” compressor styles, transformer output, a buffered bypass in/out footswitch and of course the classic API sound.
SETUP
Apply power using an external power adapter (sold separately) or an output tap
of a pedal board power distribution system.
Plug a cable from the instrument output into the TranZformer CMP INSTRUMENT
INPUT. Connect the OUTPUT to an amplifier input or the next pedal in your
chain.
USE
Starting settings: Engage footswitch, set INPUT, SUSTAIN and OUTPUT controls to 12 o’clock and WET/DRY control fully clockwise (WET).
Adjust INPUT to set input level to the compressor. Higher input level creates more compression at a given SUSTAIN setting.
Reduce INPUT to avoid clipping if needed.
Set SUSTAIN as desired for increased compression, perceived loudness, and punchiness.
Adjust the ATTACK and RELEASE controls. A FAST attack setting begins compressing the louder signals sooner and a SLOW attack time takes longer.
A FAST release setting quickly stops compressing the louder signals whereas a SLOW release time takes longer.
Set the TYPE switch to either NEW or OLD. NEW mode uses feedforward compression and gives a more modern compressed tone.
OLD mode uses feedback compression and provides a smoother, more-vintage
character.
Adjust the BLEND control to set the final output mix. Moving the control
clockwise towards WET mixes more of the compressed signal into the output.
Moving the control counterclockwise towards DRY mixes more of the uncompressed
input signal into the output signal.
Fully counterclockwise is 100% DRY and fully clockwise is 100% WET.
Set the OUTPUT control to achieve the desired final output level going into
the amplifier or the next pedal in the chain. (NOTE: Does not reduce clipping
of internal signal.)
SIGNAL FLOW (from right to left): Input > Sustain > Blend > Transformer Output
AUDIO CONTROLS
-
INPUT: Input level; +9dB to +30dB; More gain creates more compression
-
SUSTAIN (compression): Determines amount of compression (gain-reduction);
Higher levels provide more compression (lower threshold) -
BLEND: Mixes the dry (uncompressed) signal with the wet (compressed) signal.
-
OUTPUT: -inf. to 0dB output level control; 0db (no cut) is fully clockwise
SWITCHES
- A. ATTACK: Sets the compressor’s attack time to either FAST (1ms) or SLOW (10ms)
- B. RELEASE: Sets the compressor’s release time to either FAST (300ms) or SLOW (1s)
- C. TYPE: Selects between feedback (OLD) or feedforward (NEW) compression styles
- D. BYPASS: Buffered bypass footswitch
- E. Indicator LED is illuminated when pedal is engaged
CONNECTIONS
- INSTRUMENT INPUT:
- ¼” HI-Z (1MΩ), unbalanced
- POWER INPUT:
- Uses 9V to 18V DC Negative Center
- 2.1mm x 5.5mm barrel connector
- Do not use more than 18VDC
- OUTPUT:
- ¼”, unbalanced