Contents 1 Introduction 4 2 Front Panel Controls 6 3 Dynamics Control 7 3.1 Basic Dynamics Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Compressor 7 9 4.1 Compressor Threshold Control . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.2 Compressor Ratio Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.3 Compressor Soft Ratio Control . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.4 Compressor Make-Up Control . . . . . . . . . . . . .
6 Expander 31 7 Gate 32 8 Sidechain EQ 33 8.1 Sidechain EQ Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Warmth 9.1 Max Trim Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 35 36 10 Dither 36 11 Bus Compressor (TDM and AAX DSP only) 37 11.1 Description of Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 11.2 Buss Compressor Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . 40 11.
1 1 INTRODUCTION Introduction The Oxford Dynamics plug-in is a direct emulation of the extremely flexible and capable unit used in the OXF-R3 professional mixing console. Resulting from many years research into professional dynamics applications, it offers separate Compressor, Limiter, Expander, Gate and sidechain EQ functions, with fully independent control of all parameters.
1 INTRODUCTION Dynamic signal level control has grown in complexity and popularity from humble beginnings to an essential part of the sound production process. Originally conceived as a method to automatically correct for performance variation and broadcast transmission limitations, dynamic control has evolved beyond this to engender complete artistic cultures and idioms, resulting from the continuous expansion of the artistic effects provided by such processes.
2 2 FRONT PANEL CONTROLS Front Panel Controls The separate dynamics functions have their own control sets that are available at any time by operating the appropriate ACCESS button for that section. Operating the IN button for any section will force the controls for that section to the foreground of the GUI for convenience. The IN buttons can be used to toggle the contributions from each section on and off, for comparison purposes.
3 3 DYNAMICS CONTROL Dynamics Control The Dynamics section comprises of four separate applications: Compressor, Limiter, Gate and Expander. Although these applications contain several different control types that have common functions, the operation, ranges and laws of these controls have been optimised carefully for maximum flexibility within the intended specific use of that section.
3.1 Basic Dynamics Architecture 3 DYNAMICS CONTROL This method had an advantage in early analogue compressors because the complex and largely unpredictable laws of early gain reduction elements could be somewhat decoupled from the total level transfer characteristic of the application (because the design made use of level feedback).
4 4 COMPRESSOR Compressor There are two main factors that describe the function of a compressor: a level versus gain function, which is generally assumed to be independent of the time constants, and a dynamic gain function which exhibits more complex dynamic behaviour over time. To explain the operation of the compressor section, it is useful to split these two categories. The following section refers to the level versus gain behaviour of the compressor application in the Oxford Dynamics plug-in.
4.1 4.1 Compressor Threshold Control 4 COMPRESSOR Compressor Threshold Control The threshold control sets the level (referred to dB FS) at which compression and gain reduction will begin. The control has a linear decibel law over the range. The following graph illustrates the threshold control operated in 5 dB increments with the ratio at max (1000:1) to –20 dBr. 4.
4.3 4.3 Compressor Soft Ratio Control 4 COMPRESSOR Compressor Soft Ratio Control The soft ratio function provides a gentle, minimum rate transition between the region below the threshold and the compressed region of the curve. A further threshold, below the main threshold control setting, defines the start of the soft curve. The program signal is therefore compressed progressively harder as it gets louder within this region, until the full compression defined by the ratio control is achieved.
4.5 4.5 Using Level Control Functions 4 COMPRESSOR Using Level Control Functions Since all level control functions in the Oxford Dynamics Compressor operate entirely separately, a very high degree of control for a wide range of common use is possible, in particular the plug-in does not impose any particular style constraint on the user. This section explains some of the commonly used techniques, and how they may be achieved using the Dynamics plug-in.
4.6 General Programme Compression 4.6.1 4 COMPRESSOR ‘Least Possible’ Approach The first and most obvious, which we will call the ‘least possible’ approach, is to leave the majority of the programme uncompressed, forcing the compression to deal only with the louder passages. This method has a definite psychological advantage in that one gets the feeling that the majority of the programme remains unaffected.
4.6 General Programme Compression 4 COMPRESSOR One way to alleviate the compression transition effect is to smooth it out using the soft ratio function: The above graph shows the action of the SOFT ratio control set to 5dB applied to the previous settings. Starting the compression earlier, and increasing the compression ratio up to the max level point, smoothes out the transition point at the onset of compression.
4.6 General Programme Compression 4.6.2 4 COMPRESSOR ‘Overall Compression’ Approach This concept advocates that a more transparent sounding compression can be achieved if a relatively large portion of the programme level range is under continuous compression. The rationale here is that the rate of change disturbances are minimised because the compressor spends less time going over the onset of compression transition range.
4.6 General Programme Compression 4 COMPRESSOR above approaches, in order to achieve a superior result. The following graphs illustrate suggested settings to achieve some interesting dynamic results from the plug-in, by using a combination of the above approaches. 4.6.4 Maximum Loudness This graph shows one method to achieve maximum loudness and presence for programme where dynamic range is unwanted (ie. pop music, spoken commentary etc.).
4.7 Timing Functions 4.6.5 4 COMPRESSOR Minimum Obtrusion This graph shows a minimum obtrusion type curve using a ratio of around 2:1 and a soft ratio setting of 10 dB. This style of compression will bring up the softer passages by around 12 dB and progressively compress the loud passages into half the original dynamic range — in a very subtle and unobtrusive fashion.
4.7 Timing Functions 4 COMPRESSOR dependency behaviour. www.sonnox.
4.7 Timing Functions 4 COMPRESSOR To generate the timing illustration graphs, the following stimulus was used as the reference. This is a tone burst signal that consists of 0.2 sec of full level signal preceded and followed by 0.8 sec of signal at –20 dBr. 4.7.
4.7 Timing Functions 4.7.2 4 COMPRESSOR Compressor Release Control The release control varies the timing behaviour of the compressor during the recovery period after a gain reduction, when the signal level has reduced from previous levels above the threshold. release = minimum release = quarter-range release = half-range The above diagrams show that action of the release control from minimum to half range (maximum range is too long to show successfully on this diagram). www.sonnox.
4.7 Timing Functions 4.7.3 4 COMPRESSOR Compressor Hold Control The hold control varies the amount of time between a reduction of levels above the threshold and the onset of the release time. It provides a period after gain reduction where a slower rate of recovery occurs.
4.8 4.8 Compressor Timing Laws 4 COMPRESSOR Compressor Timing Laws The Oxford compressor offers three compression types designated NORMAL, CLASSIC and LINEAR, selected sequentially via a button in the centre of the Dynamics display. The time constant laws employed define the major difference between these types.
4.8 Compressor Timing Laws 4.8.1 4 COMPRESSOR Exponential/dB timing (Normal and Classic types) The Exponential/dB curve is by far the most popular law used in a great many well-respected compressors, and is the natural result of more recent analogue units employing logarithmic sidechains and resistor/capacitor time constants. The Exponential/dB law has some interesting characteristics.
4.8 Compressor Timing Laws 4.8.2 4 COMPRESSOR Linear/dB timing (Linear type) The Linear /dB law, in some respects, exhibits the reverse behaviour of the Exponential law. Because the rate of change of gain is constant (as set by the timing controls), the greater the signal dynamic excursion the longer the compressor will take to complete a gain change.
4.9 Using Compression Timing Functions 4.9 4 COMPRESSOR Using Compression Timing Functions The setting of timing functions can drastically affect the sonic character of compression, and there are many different approaches to compression timing, often in pursuit of ever-changing fashion! There is, therefore, no right or wrong approach to this task.
4.9 Using Compression Timing Functions 4 COMPRESSOR The following provides a general description of some effective approaches and starting points: 4.9.
4.9 Using Compression Timing Functions 4.9.4 4 COMPRESSOR Artistic Effects The manipulation of timing within compression can create some very useful effects. In particular, gain overshoots produced by slow to moderate attack times can be very useful at tightening up soft percussion sounds.
5 5 LIMITER Limiter From a level profile perspective, a limiter is essentially the same as a compressor with its ration set to infinity. However, the use of much faster attack times with a somewhat different dynamic behaviour allows faster and more effective reduction of peak levels. Historically, limiters were developed mainly for radio transmission systems where absolute limits on modulation were needed.
5.1 General Limiter Operation 5 LIMITER General Description The limiter’s controls are presented similarly to the compressor’s except that there is no ratio control. The time constant functions, although similar to the compressor, have different ranges. In particular the attack time can be adjusted to be much faster than the compressor.
5.2 5.2 Maximising Loudness with the Limiter 5 LIMITER Maximising Loudness with the Limiter A recent popular use of programme limiting aims to maximise the relative loudness and average modulation of music by reducing the short-term peak levels within the programme waveform. This makes it possible to increase the overall volume (gain) of a piece without getting obvious overloads (red lights) on the final mastered work.
6 6 EXPANDER Expander The dynamics’ Expander section control functions are presented similarly to the Compressor and Limiter sections, except that a RANGE control is added. The architecture of the expander conforms to what is often described as ‘downward expansion’, which means that the application only works to attenuate existing signals below a set threshold, and cannot produce any additional gain for signals above the set threshold level.
7 7 GATE Gate The Gate controls of the plug-in are presented similarly to the Expander function, except that there is no Ratio control. Programme gating has become ever more popular in recent years, since its inclusion in some professional console systems. Originally intended as a technical tool for tape noise suppression and similar functions, many useful and often fashion changing artistic effects have been achieved using gates.
8 8 SIDECHAIN EQ Sidechain EQ A high specification two-band Sidechain EQ (S-C EQ) is provided to allow de-essing and other modifications of sidechain frequency response. The EQ processing section may be routed to either the dynamics sidechain or the main signal path or both simultaneously, by selection of the independent EQ-SC and EQ SIGNAL buttons. 8.1 Sidechain EQ Controls All Gain, Frequency and Q controls operate separately, and their values are displayed permanently.
8.1 Sidechain EQ Controls 8 SIDECHAIN EQ Input Gain Adjusts the input level to the EQ section from –20 dB to 0 dB to avoid EQ clipping when in boost settings EQ S-C Routes the EQ processing into the sidechain EQ Signal Routes the EQ processing into the main signal path (SC-EQ) IN Toggles the sidechain EQ in and out for comparison purposes Note: Note that the EQ gain control is needed to avoid signal clipping when the EQ is used in the signal path with boost settings.
9 9 WARMTH Warmth The WARMTH process confers additional loudness, punch and definition to the sound of the dynamics section. The operation of this process is to impose a harmonic profile onto the signal that increases the density of higher value samples within the programme, in order to boost average modulation levels without an increase in peak levels or the risk of digital clipping. The Warmth function is engineered to achieve this without the loss of dynamic information within the programme material.
9.1 9.1 Max Trim Control 10 DITHER Max Trim Control The MAX TRIM control (only available when the WARMTH function is selected) allows very fine gain trimming on the final output of the Dynamics processing. The purpose of this function is to allow very precise alignment of maximum modulation levels, and the accommodation of the differing meter characteristics, often found in ancillary equipment used in production and mastering processes.
11 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) Bus Compressor (TDM and AAX DSP only) The Buss Compressor is a separate instantiation that allows full multi-format compression and limiting with Sub channel generation and control (up to 5.1). The Compressor, Limiter and Warmth processes are identical to the channel dynamics plug-in (as described in the preceding sections of this manual), but the Expander and Gate functions are removed to release processing load for extended multi-format application.
11.1 11.1 Description of Controls 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) Description of Controls The ‘front panel’ controls generally operate similarly to the channel compressor. The functions are listed below. 10 14 11 9 12 7 8 13 . 5 6 2 1 3 4 1. IN Button Toggle section contributions in and out for comparison purposes. Selecting IN for a main function will also force ACCESS to that section’s controls. 2. ACCESS Buttons Accesses controls for that section. 3.
11.1 Description of Controls 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) 5. Time Constant and Type Selector Selects the compressor time constant dependency laws, NORMAL, LINEAR and CLASSIC. The CLASSIC setting is a subset of the exponential type with fixed time settings corresponding to a DBX 160 type compressor. 6. External Key Input Selector (not available for VST) Selects externally derived signal to the sidechain input. 7.
11.2 11.2 Buss Compressor Architecture 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) Buss Compressor Architecture The Buss Compressor employs common sidechain processing to all buss contributions simultaneously. This avoids unwanted modification to panning and balance during compression gain changes, but it does mean that parameter settings will apply to all main busses and increased level on any buss will result in increased compression on all outputs.
11.3 11.3 Description of Sub Channel Controls 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) Description of Sub Channel Controls 3 4 5 . 1 2 ACCESS Button Accesses controls for the Sub channel processing. IN Button Toggles Sub filter in and out of the signal path. LP FILTER Sets the Sub channel filter cut off frequency between 50Hz and 150Hz (at 24dB/octave). SUB PASS Sets the proportion of the compressor contribution to the Sub channel gain, from 0 – 100 www.sonnox.
11.3 Description of Sub Channel Controls 11 BUS COMPRESSOR (TDM AND AAX DSP ONLY) SUB TRIM Sets the proportion that the Sub channel signal contributes to the compressor sidechain, from 0 – 100 Note: Note that with SUB PASS and SUB TRIM controls both set to 100%, the sub channel will be completely included in the compression function, and be treated just like the main channels.
12 12 DESCRIPTION OF CONTROLS Description of Controls This section provides a summary of the ‘front panel’ controls you will encounter when using the various sections of the Dynamics plug-in (the illustration below is of the Compressor controls): IN Buttons Toggle section contributions in and out for comparison purposes. Selecting IN will also force ACCESS to that section’s controls. ACCESS Buttons Access controls for the Sub Filter section.
12 DESCRIPTION OF CONTROLS Time Constant and Type Selector This button toggles the compressor time constant dependency laws between NORMAL, LINEAR and CLASSIC. The CLASSIC setting is a subset of the exponential type with fixed time settings corresponding to a DBX 160 type compressor. SOFT RATIO Selector Selects the soft ratio starting threshold in 5dB steps to –20dB below threshold control setting RATIO Controls the ratio of the compressor and expander processes.
12 DESCRIPTION OF CONTROLS Options Menu Clicking the Sonnox button produces a drop-down options menu (see right). Clip Lights Determines the approximate time that the overload indicator will stay on for when the plug-in has detected a full-level sample at either its input or output. Enable Sonnox Toolbar Displays or hides the Sonnox Preset Manager Toolbar Show Preset Name Path Shows the hierarchical folder path for Presets that are stored in sub-folders of the default Preset folder.
13 13 ‘ACCESS FOLLOWS’ MODES (AAX ONLY) ‘ACCESS Follows’ modes (AAX only) The AAX Native and DSP versions of the Oxford Dynamics plug-in include three extra options under the Sonnox button menu. These are intended to enhance the behaviour of the plug-in for ICON/EUCON control surface users. ACCESS follows plug-in This is the default mode. In this mode, the visible section in the plug-in GUI can only be changed by a mouse click on the GUI ACCESS buttons.
14 14 SPECIFICATIONS Specifications 14.1 Control Ranges Section Thresh Ratio/ Range Attack Hold Release (dB) (dB) GATE -80 - 0 0 - -80 5 µS[1] - 26 mS 10 mS - 10 S 7.8 - 519 mS EXP -60 - 0 0 - -80 0.26 - 104 mS 10 mS - 10 S 7.8 - 519 mS COMP -60 - 0 1:1 - Limit 519 µS - 52 mS 10 mS - 30 S 52 mS - 3.1 S LIM -60 - 0 100 µS - 500 mS 50 mS - 30 S 100 mS - 10 S Note: [1] All values in the table are referenced to full scale and time constants apply to a 10 dB gain change.
14.2 Pro Tools | HDX – Instances per chip 14.2 15 PRESET MANAGER TOOLBAR Pro Tools | HDX – Instances per chip Variant 44.1 48 88.2 96 176.
17 16 SYSTEM REQUIREMENTS Supported Platforms • Avid Pro Tools (AAX Native and DSP 32/64-bit) • VST hosts (32/64-bit) • AU hosts (32/64-bit) • Mac Intel OSX 10.6 or higher • Windows 7 and 8 (32/64-bit) 17 System Requirements For latest System requirements, please visit www.sonnox.com. All versions • Free iLok account • Appropriate product licence • iLok2 Pro Tools • Approved Digidesign/Avid CPU and hardware configuration • Pro Tools 10.3.
18 18 COPYRIGHT AND ACKNOWLEDGEMENTS Copyright and Acknowledgements Trademarks and content copyright © 2007-present Sonnox® Ltd. All rights reserved. Sonnox® and the five dots logo are registered trademarks of Sonnox Ltd. This product is manufactured and supplied by Sonnox Ltd. This product is protected by one or more European and/or US patents. DIGIDESIGN, AVID and PRO TOOLS are trademarks or registered trademarks of Avid Technology Inc. VST is a trademark of Steinberg AG.
