Widen your mixes and recover the natural ambience of your recorded sources.
The Precision K-Stereo Ambience Recovery plug-in for UAD-2 and Apollo interfaces allows you to precisely enhance the stereo depth and imaging of your mixes without unwanted artifacts.
Created for the UAD platform with famed mastering engineer Bob Katz, the Precision K-Stereo plug-in is designed for critical 2-track mastering applications — from jazz to rock to hip-hop — and is the natural-sounding cure for busy or narrow-sounding mixes.
- Add depth and imaging to instruments and vocals without adding artificial reverb
- Extract ambience from source material, naturally, adding depth and width to the stereo field
- Harness Mid/Side gain controls to adjust the center-to-side balance of mixes
- Tweak further with powerful three-band Ambience Filter EQ
Precision K-Stereo
Operational Overview
Ambience Recovery
The primary function of Precision K-Stereo is for ambience recovery and enhancement. The plug-in doesn't add new ambience or change the balance of the mix. Instead, it extracts, recovers, polishes, and embellishes the ambience that already exists in a source recording.
Precision K-Stereo does not use any comb filters, matrixing, phase processing, or related techniques which are used in typical image processors. Instead, the ambience recovery process is accomplished using established psychoacoustic principles. The result is a smooth, natural, phase-coherent, and mono-compatible sound that meets professional mastering standards.
In addition to ambience level and enhancement adjustments, the ambient portion of the source material can be further equalized using low/high cut filters and a fully parametric bell filter. These ambience filters affect the "wet" signal only and are completely independent from the "dry" portion of the recording.
Primary Application
Precision K-Stereo is designed for use during the mastering process to fine-tune the ambience that exists in previously-mixed stereo program material. Generally speaking, adjusting ambience during multitrack mixdown is best managed within the mix itself because of the higher level of control and detail available at that stage.
Of course, Precision K-Stereo can be used across the stereo bus during mixing and/or in other creative applications as well. However, since the process is optimized for broad spectrum mixes with at least some ambient content, the effect may be extremely subtle on individual tracks, depending on the ambient content in the recording.
Mid/Side Leveling
The Precision K-Stereo processor does not use or require mid/side encoding or decoding techniques to achieve ambience recovery nor enhancement. However, the plug-in has an independent mid/side ratio leveling feature that can be useful during mastering to compensate for overall center-to-side level imbalances within the stereo field.
The ambience recovery feature can then be used to recover ambience and space that is lost when the mid-channel level is increased (such as when raising a center-located vocal or instrument).
Configurations
Precision K-Stereo is optimized for use in stereo-in/stereo-out configurations. However, ambience recovery is possible on monophonic source recordings when the plug-in is used in a mono-in/stereo-out (MISO) configuration. Mono signals are "stereo-ized" in the MISO context.
Note: Due to the inherent stereo nature of the ambience recovery process, Precision K-Stereo is not intended for use in mono-in/mono-out configurations.
Presets
Precision K-Stereo includes factory presets designed by Bob Katz. A list of these presets and their application notes are at the end of this chapter.
Precision K-Stereo Controls
Control Arrangements
Precision K-Stereo controls are grouped into four sections: Ambience Recovery, Ambience Filters (EQ), Mid/Side Gain, and Left/Right Gain. The detailed control descriptions that follow are similarly grouped.
Control Adjustments
Switches
For the main switches (Recover, M/S Gain, etc.), click the switch to toggle its setting. The switch is engaged when it is illuminated.
Switch toggled on (left) and off (right)
Knobs
For the knob controls, values can be adjusted with the mouse or values can be entered directly via text entry. Additionally, when the tickmarks and/or values around the knob are clicked, the knob will jump to that setting.
Tip: The "big knobs" (Ambience Gain, Mid/Side Gain, and L/R Gain) can be returned to the zero value by clicking the zero label above the knobs.
Ambience Recovery
Ambience Recovery controls
Recover Enable
This switch enables/disables the ambience recovery process. See Ambience Recovery for an overview.
Recover Enable must be engaged for the Ambience Gain, Enhance Deep/Wide, and Ambience Filters controls to have any effect.
Note: This switch does not have any effect on the M/S Gain, L/R Gain, or Power controls.
Ambience Gain
The Ambience Gain knob controls the level of recovered ambience. The default 0 dB position is defined as the nominal or "typical" setting (ambience recovery is occurring when set to 0 dB).
Increase or decrease Ambience Gain to change the amount of recovered ambience. The range is -20 dB to +9 dB, available in 0.5 dB steps. Click the "0" label to quickly return to 0 dB. To disable ambience recovery, use the Recover Enable switch.
Note: Values below 0 dB do not remove ambience.
Enhance
The ambience recovery process can be manipulated further with the Deep and Wide switches.
Note: The Enhance functions can only be enabled when the Recover switch is engaged.
Deep
Provides deeper ambience recovery when the switch engaged.
Wide
Spreads and enhances the stereo image when the switch is engaged.
Ambience Filters
The Ambience Filters (EQ) provide for frequency adjustments to the ambient portion of the signal. These controls do not affect the direct (dry) portion of the signal.
The Ambience Filters consist of one Low Cut filter, one High Cut filter, and a single-band parametric bell filter.
Note: Controls in the Ambience Filters section can only be modified when the Recover Enable switch is engaged.
Ambience Filters controls
EQ Enable
The EQ switch enables/disables the Ambience Filters. This switch can only be engaged when the Recover Enable switch is engaged.
Cut Filters
The Low Cut and High Cut filters (the left-most and right-most knobs in the Ambience Filters section) have a slope of 12 dB per octave. Each Cut Filter can be independently disabled by setting it to the OFF position (the default value).
Tip: To quickly disable a cut filter, click its OFF text label.
Low Cut
The available range is 20 Hz to 1 kHz.
High Cut
The available range is 5 kHz to 20 kHz.
Bell Filter
The bell filter is fully parametric, with independent control of frequency, Q (bandwidth), and gain.
Bell Filter controls
Bell Frequency
This control sets the center frequency of the bell filter. The available range is 150 Hz to 10 kHz.
Bell Q
Bell Q determines the bandwidth of the bell filter. The available range is 0.5 to 3. Smaller Q values cause the bell filter to effect a broader portion of the frequency spectrum, while high Q values effect a narrower spectrum.
Bell Gain
Bell Gain determines how much boost or cut is applied to the bell filter. The available range is ±10 dB. To quickly return to the 0 dB setting, click the GAIN text label.
Note: The two other Bell parameters (Frequency and Q) have no effect when Bell Gain is set to 0 dB.
Mid/Side Controls
The Mid/Side controls allow for level adjustments to the middle (center) and side portions of signals within a stereo field. Mid/Side adjustments can be made when ambience recovery is active or disabled. Note that the ambience recovery process does not use or require mid/side techniques to achieve ambience recovery or enhancement.
Note: The Mid/Side controls are disabled when the plug-in is used in a mono-in/mono-out configuration.
Mid/Side controls
M/S Gain Enable
This switch enables/disables the Mid Gain and Side Gain controls.
Mid Gain
Mid Gain adjusts the level of signals in the middle of a stereo signal. The available range is -12 dB to +6 dB, in steps of 0.1 dB. To quickly return to the 0 dB setting, click the MID text label.
Side Gain
Side Gain adjusts the level of signals at the sides of a stereo signal. The available range is -12 dB to +6 dB, in steps of 0.1 dB. To quickly return to the 0 dB setting, click the SIDE text label.
Output Gain Controls
Output Gain controls
L/R Gain Enable
This switch enables/disables the Left/Right Gain and Link controls.
Link
This switch links (gangs) the Left/Right Gain controls for ease of operation when both channels require the same value. Disable Link when independent left/right control is desired.
Note: When Link is inactive and Link is engaged, the left gain value is copied to the right gain. Any offset between the gain values is lost.
Left/Right Gain
The independent Left and Right Gain have an available range of -24 dB to +12 dB, available in 0.1 dB steps. To quickly return to the 0 dB setting, click the respective LEFT or RIGHT text labels.
Note: The right channel gain control is disabled when the plug-in is used in a mono-in/mono-out configuration.
Output Level Meters
The stereo peak/hold meters display the signal level at the output of the plug-in. The meter range is from -30 dB to 0 dBFS. Signal peaks are held for 3 seconds before resetting.
Note: Both meters are active and display identical levels when the plug-in is used in a mono-in/mono-out configuration.
Output level meters
Power
When the Power switch is in the OFF position, the interface elements do not illuminate, plug-in processing is disabled, and UAD DSP usage is reduced (unless UAD-2 LoadLock is enabled).
Click the switch or the OFF/ON labels to change the setting, or click the UA logo to toggle the setting.
Factory Preset Notes by Bob Katz
Precision K-Stereo includes factory presets designed by Bob Katz for use with his signature plug-in. Descriptions about these presets are listed below.
The Default preset and presets with the "BK" prefix are the settings created by Mr. Katz. Two categories are included: "MIX" presets for use during mixing, and "MSTR" for use during mastering.
Default
When Precision K-Stereo is instantiated, it automatically starts with the Default preset, which sets the Ambience Level to 0 dB (a nominal starting point which works well with a lot of music), engages Wide and Deep, and sets everything else to neutral. Feel free to turn the Ambience Level up or down to taste or to explore the possibilities. The rest of the factory presets are provided to demonstrate possibilities, but since there are very few controls, it's easy to get the Precision K-Stereo working for any situation.
BK-MSTR-Rock Tight Bass
This preset has Ambience Level at 0 dB, Wide and Deep engaged, and the Ambience Low Cut filter set to 125 Hz to maintain a tight bass instrument while increasing the size and depth of the rest of the instruments.
BK-MSTR-Rock Tight Drums
This preset has Ambience Level at 0 dB, Wide and Deep engaged, Ambience Low Cut filter set to 125 Hz, Ambience High Cut Filter set to 10 kHz. This maintains the bass instrument tight (not as affected by the Ambience Level) as well as softens the ambience of the high frequencies to tighten the percussion, but it retains ambience in the midrange to enhance vocals and midrange instruments.
BK-MSTR-String Ensemble
This preset has Ambience Level at +1 dB, Wide is disengaged, Deep is engaged. This is very useful, as the name implies, for enhancing the ambience of a small ensemble or solo instrument without stretching it to the extreme sides, maintaining the ensemble's small size but still help its richness and depth. Try this preset during mixing on a stereo-miked solo guitar (instead of a reverb chamber).
BK-MSTR-Full Orchestra A
This is the same as the default preset. Turn the Ambience Level up or down to taste. Perhaps add some Ambience EQ to warm up the sound, or add some presence to the ambience, depending on the nature of the reverberation in the original recording.
BK-MSTR-Full Orchestra B
Same as Full Orchestra A, but the high cut filter is set to 10 kHz which softens the high frequency ambience to tighten the percussion.
BK-MSTR-Clear Presence
If the hall or chamber in the original recording is missing some presence, here's a suggestion on what to do.
BK-MSTR-Raise Mid Instruments
This preset subtly raises the Mid level 1 dB above the side level and recovers a bit of the spacious ambience which is commonly lost when the mid/side ratio is raised.
BK-MSTR-Warm Ambience
This preset adds overall warmth to the recovery settings.
BK-MIX-Big Steinway
Try this preset on a stereo recording of a piano to enhance the size and body of the instrument without losing its definition. This preset will illustrate how ambience EQ is very different from direct EQ. Here we turn up the bottom end and lower midrange of the ambience channel. It might turn a six-foot Yamaha into a nine-foot Steinway, so be careful, or maybe that's exactly what you want to do!
BK-MIX-Big
This preset turns up the ambience level a bit to quickly show you the possibilities.
BK-MIX-Too Big
This preset turns up the ambience level very far to quickly show you extreme possibilities.