The Equaliser panel is used to select the type of equaliser whose responses
REW is to model. Changing the equaliser type updates the filter panel,
applying the settings appropriate to the selected equaliser. Filters already
defined are retained where possible, but parameter values will be adjusted if
necessary to comply with the ranges and resolutions of the chosen equaliser.
The currently selected equaliser is shown in the panel title and in the EQ Filters
panel.
- TMREQ
- The TMREQ equaliser setting offers the full range of filters and filter settings
supported by TMREQ (peaking = parametric, low pass, high pass, low shelf,
high shelf and notch). For the Peaking filters the bandwidth in Hz between
the half gain points is given by:
Bandwidth = centre frequency/Q
The TMREQ setting allows 8 filters. The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 1 Hz
|
| Gain | -15 | +6 | 0.1 dB
|
| Q | 0.1 | 50 | 0.1
|
- BFD Pro DSP1124P
- The DSP1124P equaliser setting supports the DSP1124P's parametric filters,
allowing 12 filters. The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | see below
|
| Gain | -48 | +16 | 1 dB
|
| BW/60 | 1 | 120 | 1
|
The frequency control adjusts in the pseudo-1/60th octave steps DSP1124P
supports (20 evenly spaced subdivisions of the ISO one-third octave intervals),
with the one-third octave and fine adjustment values DSP1124P uses shown
alongside the actual frequency in the EQ Filters Panel.
The "BW/60" control replicates the effect of the DSP1124P's bandwidth
setting. This control sets the bandwidth of the filter between the
half-gain points with:
Bandwidth (Hz) = centre frequency*(BW/60)*sqrt(2)
For example, at a bandwidth setting of 60/60 a filter centred on
1kHz with a gain of -6dB will have a bandwidth of 1,414Hz between the
points where its response crosses -3dB. This bandwidth remains constant as the
filter's gain is adjusted (Note that the Behringer DSP1100 software
package does NOT correctly reproduce the way the bandwidth
control actually operates, its bandwidths are too small by a factor
of sqrt(2)).
Defining filter bandwidth in this way is not uncommon (the TMREQ filters
use a similar definition). The relationship between Q and BW for the DSP1124P
is
Q = 60/[(BW/60)*sqrt(2)]
so the bandwidth range of 1/60 to 120/60 gives a Q range from 42.4 to 0.35.
- BFD Pro FBQ2496
- The FBQ2496 equaliser setting supports the FBQ2496's parametric filters,
allowing 20 filters. The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 1/60th octave
|
| Gain | -36 | +15 | 0.5 dB (1 dB below -15 dB)
|
| Bandwidth | 1/60 | 10 | octaves, see below
|
The frequency control adjusts in approximately 1/60th octave steps (more
precisely, 1/200th of a decade).
The bandwidth control adjusts in 1/60 of an octave steps from 1/60 to
5/60 of an octave, then goes through 1/10, 1/9, 1/8, 1/7, 1/6,
1/5, 1/4, 1/3, 1/2, 3/4, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 10 octaves.
The relationship between Q and BW in octaves for the FBQ2496 is
Q = sqrt(2)/BW
so the bandwidth range of 1/60 to 10 octaves gives a Q range from 84.85 to 0.14.
- DCX2496
- The DCX2496 equaliser setting supports parametric filters (labelled "BP" for
Band Pass) and low and high shelving filters (with 6 and 12 dB/octave
slopes). It allows up to 9 filters per channel, depending on the other
processing the unit is doing. The parametric filter bandwidth in Hz
between the half gain points is given by:
Bandwidth = sqrt(gain)*centre frequency/Q
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 106 steps per decade
|
| Gain | -15 | +15 | 0.1 dB
|
| Q | 0.1 | 10 | 20 steps per decade
|
The frequency control adjusts in steps of 1/106th of a decade. The Q
control adjusts in steps of 1/20th of a decade, i.e. there are 20 Q
values between 0.1 and 1 and another 20 between 1.0 and 10.
- SMS-1
- The SMS-1 equaliser setting supports parametric filters only, allowing 8
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = centre frequency/Q
N.B. The SMS-1 filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 15 | 120 | 1 Hz
|
| Gain | -13 | +6 | 0.5 dB
|
| Q | 0.3 | 20.0 | 0.1
|
- R-DES
- The R-DES equaliser setting supports parametric filters only, allowing 5
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = 1.766*centre frequency/Q
N.B. The R-DES filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 120 | 1 Hz
|
| Gain | -10 | +10 | 0.1 dB
|
| Q | 1 | 15 | 0.1
|
- QSC DSP-30
- The DSP-30 equaliser setting supports parametric filters only, allowing 20
filters. The filter bandwidth in Hz between the half gain points is given by:
Bandwidth = centre frequency/Q
N.B. The DSP-30 filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 0.1 Hz
|
| Gain | -120 | +12 | 0.1 dB
|
| Q | 0.3 | 50 | 0.01
|
- Crown USM-810
- The USM-810 equaliser setting supports parametric filters only, allowing 10
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = sqrt(gain)*centre frequency/Q
N.B. The USM-810 filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 1 Hz
|
| Gain | -24 | +24 | 0.1 dB
|
| Q | 0.1 | 35 | 0.01
|
- ADA PEQ
- The ADA equaliser setting supports parametric filters only, allowing 12
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = centre frequency/Q
N.B. The ADA filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 1 Hz
|
| Gain | -10 | +10 | 0.5 dB
|
| Q | 0.1 | 10 | 0.1
|
- Xilica XP2040
- The XP2040 equaliser setting supports parametric filters only, allowing 16
filters. The filter bandwidth is specified in octaves, but the corresponding
bandwidth in Hz is shown in the filter controls panel.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 30000 | 1 Hz
|
| Gain | -30 | +15 | 0.25 dB
|
| BW | 0.02 | 3.61 | 0.01 octaves
|
- MiniDSP
- The MiniDSP equaliser setting supports the same filter types and resolutions as the
Generic setting, but for 6 filters. It is aimed at the MiniDSP plug-in Advanced
mode, which allows filters to be specified by their biquad coefficients. The
Save Filter Coefficients to File action writes the filter coefficients
to a file in a format suitable for use with the MiniDSP software (note that the
a1 and a2 coefficients are negated per the MiniDSP format). An advantage of
this is the very high filter frequency and Q resolution it allows, permitting
exact targeting of modal resonances. The MiniDSP plug-in has an Import REW File
button on its Parametric EQ configuration screens to load the files.
- MiniDSP-96k
- The MiniDSP-96k equaliser setting supports the same filter types and resolutions as the
Generic setting, but for 5 filters. It is aimed at MiniDSP plug-ins that operate at 96 kHz.
- nanoAVR
- The MiniDSP nanoAVR equaliser setting supports the same filter types and resolutions as the
Generic setting, but for 10 filters.
- waveFLEX DSP A8
- The DSP A8 equaliser supports the same filter types and resolutions as the
Generic setting, but for 5 filters operating at 96 kHz.
- Emotiva UMC-200
- The UMC-200 equaliser setting supports parametric filters only, allowing 11
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = sqrt(gain)*centre frequency/Q
N.B. The UMC-200 filter shapes have not been verified against an actual unit.
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 256 steps
|
| Gain | -15 | +3 | 0.25 dB
|
| Q | 0.25 | 24 | 0.125
|
- Emotiva XMC-1
- The XMC-1 equaliser setting supports parametric filters only, allowing 11
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = centre frequency/Q
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 1 Hz
|
| Gain | -64 | +6 | 0.5 dB
|
| Q | 0.6 | 50 | 0.01
|
- Dual Core
- The Dual Core equaliser setting supports parametric filters only, allowing 16
filters. The filter bandwidth in Hz between the half gain points is given by:
Bandwidth = sqrt(gain)*(-3dB BW)
Q = centre frequency/(sqrt(gain)*(-3dB BW))
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 5 | 20000 | 1 Hz
|
| Gain | -36 | +12 | 0.1 dB
|
| -3dB BW | 1 | 10000 | 1
|
- Rockford Fosgate 3Sixty.3
- The 3Sixty.3 equaliser setting supports parametric filters only, allowing 20
filters. The filter bandwidth in Hz between the half gain
points is given by:
Bandwidth = sqrt(gain)*centre frequency/Q
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 20 | 20000 | 0.1 Hz
|
| Gain | -24 | +24 | 0.1 dB
|
| Q | 0.1 | 6 | 0.01
|
- rePhase
- The rePhase equaliser setting supports parametric filters only. It
allows up to 17 filters per channel. The parametric filter bandwidth in
Hz between the half gain points is given by:
Bandwidth = sqrt(gain)*centre frequency/Q
The adjustment ranges are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 10 | 24000 | 0.01 Hz
|
| Gain | -96 | +96 | 0.1 dB
|
| Q | 0.1 | 10 | 0.01
|
- Generic
- The Generic Equaliser supports a full range of filters and filter
settings (peaking = parametric, low pass, high pass, low shelf, high shelf
and notch) based on the Robert Bristow-Johnson 'Cookbook' equations. The
Save Filter Coefficients to File action writes the filter
coefficients corresponding to the selected sample rate to a file in a
format compatible with MiniDSP software (note that the a1 and a2 coefficients
are negated per the MiniDSP format). For the Peaking filters the bandwidth
in Hz between the half gain points is given by:
Bandwidth = centre frequency/Q
The Generic setting allows 20 filters. The adjustment ranges
are:
| Parameter | Minimum | Maximum | Resolution
|
|---|
| Frequency | 10 | 22000 | 0.01Hz below 100Hz, 0.1Hz below 1kHz, 1Hz above 1kHz
|
| Gain | -120 | +30 | 0.1dB
|
| Q | 0.1 | 50 | 0.01
|
