Original UA designed, premium performance brickwall limiter.
The Precision Limiter plug-in for UAD-2 hardware and Apollo interfaces is a single-band, look-ahead brickwall limiter made primarily for use with program material. Easy to use, the Precision Limiter plug-in is a colorless, transparent mastering limiter.
No upsampling is used, nor does the Precision Limiter pass audio through any filters — audio remains untouched unless the compressor is working, in which case, only gain is affected.
- Use the unique Contour Mode to tweak the attack, shape, and character of a track
- Easily prevent clipping on masters, tracks, and buses
- Harness colorless limiting for maximum transparency
- Meter with professional accuracy using Bob Katz's "K-system" metering specs
Precision Limiter
Precision Limiter Controls
Precision Limiter introduced a new control style for UAD plug-ins. For the Mode, Meter, Scale, and Clear parameters, click the parameter label, the value text, or the LED to toggle between available values.
Input
The Input knob controls the signal level that is input into the limiter. Increasing the input will result in more limiting as the input signal exceeds 0 dB.
The default value is 0 dB. The available range is -6 dB to 24 dB.
Output
The Output knob determines the maximum level at the output of the plug-in. This control does not affect the actual limiting.
Precision Limiter always limits the signal to 0 dB internally, and the actual output is set by attenuating this internal level. Likewise, the input control can drive the signal over 0 dB to get more limiting.
If Precision Limiter is the last processor in the signal path when mixing down to disk (bouncing), the Output value will be the level of the highest peak in the resultant audio file.
The default value is -0.10 dB. The available range is from -12 dB to 0 dB. Non-zero values are always negative, therefore during text entry operations positive or negative values may be entered and the result will be negative.
Release
The Release knob sets the value of the limiter release time. The default value is Auto. The available range is from 1 second to 0.01 milliseconds.
Auto Mode
When the Release knob is fully clockwise, Automatic mode is active. In Auto mode, release time is program-dependent. Isolated peaks will have a fast release time, while program material will have a slower release.
Tip: Type "A" or "a" to enter Auto mode during text entry.
Mode
The Mode switch affects the attack shape of the limiter. Subtle tonal variations are possible by switching the Mode between A and B.
Mode A is the default shape, suitable for most material, while Mode B can be particularly useful on minimal and/or acoustic program material, yielding a more subtle touch.
Power
The Power switch determines whether the plug-in is active. When the Power switch is in the Off position, plug-in processing is disabled and UAD DSP usage is reduced (unless UAD-2 DSP LoadLock is enabled).
When the plug-in is bypassed with this switch (but not by the host bypass), the VU meter displays the unprocessed input signal level.
Precision Limiter Meters Overview
K-System
Precision Limiter has precise, calibrated stereo metering. It offers the option to use K-System metering, which is a method devised by renown audio engineer Bob Katz. The K-System is essentially a method of integrating metering and monitoring levels to standardize the apparent loudness of audio material while providing useful visual feedback of average and peak levels.
Integrated Meter/Monitor System
The K-System is not just a metering system; it is designed to be integrated with calibrated monitoring system levels. In a full K-System implementation, 0 dB on the level meter yields 83 dB sound pressure level (SPL) per channel in the monitor output level (86 dB running two channels in stereo), when measured with 20-20 kHz pink noise on an SPL meter set to C-weighted slow (i.e. average) response. It is this calibrated meter/monitor relationship that establishes a consistent average "perceived loudness" with reference to 0 dB on the meter.
Sliding Meter Scale
With the K-System, programs with different amounts of dynamic range and headroom can be produced by using a loudness meter with a sliding scale, because the moveable 0 dB point is always tied to the same calibrated monitor SPL. Precision Limiter provides several meter ranges for various types of program material (see Type).
Long Live Dynamic Range!
The K-System can help combat the bane of the "loudness wars" which is all-too common in today's music, whereby material is made to appear louder when compared to other material at the same playback volume, at the expense of dynamic range and fidelity.
Type
The Type switch defines the 0 dB point in the Sliding Meter Scale. There are three different K-System meter scales, with 0 dB at either 20, 14, or 12 dB below full scale, for typical headroom and SNR requirements of various program materials.
Each of these modes displays the The RMS and instantaneous peak levels, which follow the signal, and the peak-hold level (see Meter Response).
Note: When the meters are in the K-modes, the displayed RMS level is 3.01 dB higher when compared to the same signal level in the Peak-RMS mode. This is done to conform to the AES-17 specification, so that peak and average measurements are referenced to the same decibel value with sine waves.
K-20
K-20 mode displays 0 dB at -20 dB below full scale. K-20 is intended for material with very wide dynamic range, such as symphonic music and mixing for film for theatre.
K-20 Meter Type
K-14
K-14 mode displays 0 dB at -14 dB below full scale. K-14 is intended for the vast majority of moderately-compressed material destined for home listening, such as rock, pop, and folk music.
K-14 Meter Type
K-12
K-12 mode displays 0 dB at -12 dB below full scale. K-12 is recommended for material intended for broadcast.
K-12 Meter Type
Peak-RMS
This is what is often considered a "normal" digital meter, where 0 dB is full-scale digital code.
Peak-RMS Meter Type
Meter Response
The main stereo Input/Output meter actually displays three meters simultaneously: The RMS and instantaneous peak levels, which follow the signal, and the "peak-hold" (also known as global peak) level.
The peak-hold level is the maximum instantaneous peak within the interval set by the Hold button, and is also displayed as text to the right of the meters. To reset the peak hold levels, press the Clear button.
Precision Limiter metering is also active when plug-in processing is deactivated with the Power switch. Metering is disabled when the plug-in is bypassed by the host application.
Gain Reduction Meter
The Gain Reduction meter displays the amount of limiter gain reduction. More green bars moving to the left indicate more gain reduction is occurring.
Gain reduction only occurs when the input signal level exceeds 0 dB. Therefore, increasing the Input knob usually results in more gain reduction.
Meter
The Meter switch specifies the signal source for the main stereo meter, either input or output.
Input
When the Meter switch is in Input mode, the main level meters display the signal level at the input of the plug-in (and is not affected by the Input knob).
Output
When the Meter switch is in Output mode, the main level meters display the level at the output of the plug-in. When the Limiter is enabled, the Output and Input knobs will affect this display.
Scale
The meter Scale switch increases the resolution of the main stereo level meter. The meter range that is displayed in Normal and Zoom modes is dependent upon the meter Type setting.
Precision Limiter meter scale in PK-RMS Zoom mode
The main level meters in Normal mode, and the gain reduction meter in both Normal and Zoom modes, are linear (level differences between LED segments is the same). In PK-RMS and K-20 Zoom modes however, the main level meters use two different linear ranges for increased accuracy.
The ranges and response for each meter type and scale is detailed below.
PK-RMS
In Normal mode, the meter range is -60 dB to 0 dB with a linear response of 0.5 dB per segment. In Zoom mode, the range is -18 dB to 0 dB with two different linear responses: 0.2 dB per segment from -18 to -6 dB, and 0.1 dB per segment from -6 to 0 dB.
K-20
In Normal mode, the meter range is -40 dB to 20 dB with a linear response of 0.5 dB per segment. In Zoom mode, the range is -8 dB to 20 dB with two different linear responses: 0.2 dB per segment from -8 to 15 dB, and 0.1 dB per segment from 15 dB to 20 dB.
K-14
In Normal mode, the meter range is -46 dB to 14 dB with a linear response of 0.5 dB per segment. In Zoom mode, the range is -10 dB to 14 dB, with linear response of 0.2 dB per segment.
K-12
In Normal mode, the meter range is -48 dB to 12 dB with a linear response of 0.5 dB per segment. In Zoom mode, the range is -12 dB to 12 dB, with linear response of 0.2 dB per segment.
Hold
The meter Hold Time switch determines how much time will pass before the peak values for the main meter and the gain reduction meter are reset. It affects both the peak LED's and the peak text display.
Values of 3 seconds, 10 seconds, or Infinite (indicated by the lazy-8 symbol) can be selected.
Clear
The meter Peak Clear switch clears the meter peak value display. It affects both the peak LED's and the peak text display.