API Vision Channel Strip

API Vision combines a 212L preamp, 215L sweep filters, 235L gate/expander, 225L compressor/limiter, and a selectable EQ module. Choose either the four-band 550L or ten-band 560L; their settings are retained when switching, but they are alternative EQ modules rather than two simultaneous equalizers.

Routing is central to its flexibility. EQ normally follows dynamics, PREDYN moves it ahead, and sidechain buttons remove filters or EQ from the audible path and use them to control dynamics instead. This allows frequency-conscious compression or gating without necessarily applying that frequency shaping to the output.

Unlike Vision Legacy, this version has separate mic/line gains and pads, a dedicated preamp rumble filter, and modeled output buffer clipping and console fader. Lowering the fader cannot undo clipping that occurred in the preceding buffer. Establish input drive first, activate only the modules you need, choose their routing, then set the final level. Apollo Unison interaction requires the dedicated Unison slot; ordinary inserts retain the software processing without physical preamp integration.

Manual — sections: Operational Overview; Modular Design; Signal Flows; Global Module.

• 212L Input / Gains: Select Mic or Line. Mic spans 30–65 dB, default 40.5; Line spans 0–12 dB, default 0. PAD attenuates Mic by 20 dB or Line by 6 dB; Line PAD is unavailable in Unison. Phase inverts polarity. Cut enables a 50 Hz, 6 dB/octave rumble filter. The ladder meter reads preamp output.
• 215L Hi-Pass / Lo-Pass: Low cut sweeps 12–596 Hz at 12 dB/octave; high cut sweeps 643 Hz–40.8 kHz at 6 dB/octave. ON enables the module. SC removes these filters from the audio path and routes them to both dynamics detectors.
• 235L Threshold / Depth: Threshold spans +25 to −47 dB; signals below it are attenuated. Depth spans 0 to −80 dB, with finer scaling near subtle attenuation. GTE/EXP chooses gating or fixed 1:2 downward expansion.
• 235L Attack / R/H: Choose Normal 25 ms or Fast 100 microseconds. Release/Hold spans 50 ms–3 seconds. REL/HLD selects decay time or gate hold time; Hold is unavailable in Expander mode and uses a fixed 100 ms release. ON enables processing; its meter shows attenuation.
• 225L Threshold / Ratio: +13 to −18 dB threshold; continuous 1:1–infinity ratio. Makeup gain is automatic and not perfectly linear. Attack offers 2, 18, or 75 ms; Release spans 50 ms–3 seconds with program dependence.
• 225L Knee / Type / ON: Choose Soft/Hard onset and OLD feedback/NEW feed-forward detection. Sidechain filtering also works in OLD in the plug-in. The module meter displays gain reduction.
• 550L Frequency / Gain: Four concentric pairs select frequency and stepped gain: 0, ±2, ±4, ±6, ±9, ±12 dB. LF covers 30–400 Hz, LMF 75 Hz–1 kHz, HMF 800 Hz–12.5 kHz, and HF 2.5–20 kHz at the documented discrete choices. LF/HF switches choose peak or shelf. Proportional Q narrows bands with greater adjustment.
• EQ Type / 560L: TYPE swaps equalizers. The graphic EQ offers ±12 dB at 31, 63, 125, 250, 500 Hz and 1, 2, 4, 8, 16 kHz. It has approximately 0.4 dB insertion boost even with flat sliders.
• EQ Routing / ON: PREDYN places EQ before dynamics. DYN SC sends EQ only to detection and overrides PREDYN. ON enables EQ.
• Global: SC Link couples stereo dynamics to stabilize imaging. The output fader supplies up to +9 dB but follows buffer clipping. The output meter reads peaks; Power bypasses all processing.

Manual — sections: 212L Microphone Preamplifier; 215L High/Low Sweep Filters; 235L Gate/Expander; 225L Compressor/Limiter; 550L Four-Band Equalizer; 560L Ten-Band Equalizer; Global Module.