Power On and Software Version Check
The first thing we should do is check the software version of the 2496. This is done by pressing the "UTILITY" button. The version
is reported in the upper right hand corner of the display window. Version 2.5 is the latest software revision by Behringer and includes
a few bug fixes as well as a few more variable functions. If your version is below this, consider downloading
the latest software version and downloading the "Midi-Ox" midi
control program used to transfer the software information from your computer to the 2496. Instructions on how update the 2496
via a midi transfer is available on the "DEQ2496-upgrade"
section on the bottom of this page.
Menus and Setup
The main menus are accessed by pressing one of the 9 buttons on the right side of the 2496.
First, you should set the rear-panel "
MAX" switch to a level of
+22 dBu. (Level button pressed
"IN") This establishes an extra +10dBu of maximum gain capability and will allow a little more "headroom" for signal
peaks.
UTILITY Menu Pages 1, 2 & 3
Pressing the UTILITY button will display one of three "PAGES" of menus. Select Page 1 (GENERAL SETUP) by pressing the "PAGE"
button just to the top-left of the main display. Adjust the contrast of the display by first selecting CONTRAST by rotating the small top
knob marked PUSH / TURN. A little arrow to the left of the display will move as you rotate the knob. Once the arrow is pointing to CONTRAST,
change it's value by turning the big knob. Select what works best for you.
Following the same procedures for selection and parameter values, make sure that values indicated on pages 1, 2 and 3 of the UTIL menu
are as shown below:
You will want to make sure that the "CHANNEL MODE" is set to "DUAL MONO". Since we will be working
with a MONO signal, "DUAL MONO" will allow independant Right/Left processing settings. We can then use each channel for a different
purpose, like for example, using the Left channel for our transmiter audio and the Right channel for our receiver audio. It's like having
two MONO DEQ2496's in one!
BYPASS Menu
The "Bypass" menu allows you to select which modules you will or will not be using. I would suggest bypassing the modules you
will not be using. You do this by selecting the module using the big knob, and then pushing the big knob resulting in a module that is
"X'ed" out. If you will only be using the Left channel, you can bypass the entire right channel by pressing the small bottom
knob in once. You will then see a straight line through everything in the right channel indicating that it's hardwire bypassed. I chose
to bypass the left channel "GEQ" module since I ill not really need this if the PEQ module is properly set up. On the right channel,
I have disabled all modules, accept for the "GEQ", which I use for transmitter monitoring purposes. See the illustration below:
I/O Menu Page 1
The "I/O" menu (Input / Output) allows you to configure which inputs and outputs you will be using and also configures the RTA
(Real Time Analyzer) input source. The only menu we need to be concerned about is on Page 1. The INPUT source should be set to "MAIN
IN", the clock should be set to "96.0" and the "GAIN" should be set to "-60.0".
See the illustration below:
Initial Preamp Levels Feeding the DEQ2496
Press the "METER" button and make sure that you are on Page 1 using the "Page" button. Press the ""A"
button making sure that the meter is reading "INPUT" as the source. The DEQ2496 will now read the level of signal coming in
from the device that's feeding it, usually the microphone preamp output.
Adjust your microphone preamp output control so that the 2496 Left input "Peak" level (top shaded scale) reads about -25dB
in real-time as you are speaking normally. Don't worry if your input meter reads up to -10dB on voice peaks as this is normal. You are
now ready to continue with the DEQ2496 settings.
Behringer DEQ2496 Universal Critical Timing and DEQ Parameters
The following universal parameters (useful for all applications) were derived from extensive testing by Tyler, KA0KA, using his function
generator and an oscilloscope to determine the best timing and frequency/BW parameters for minimal distortion of a sign wave source at
the output of the DEQ2496.
In addition, the DEQ center frequencies, and their respective bandwidths, have been optimized to simulate a true multi-band compressor
covering the entire 20Hz~20kHz audio spectrum, even though the higher frequencies above about 10kHz are irrelevant in our application.
To show an example of incorrect timing parameters vs. corrected timing parameters, see the following scope patterns:
Incorrect Behringer DEQ2496 DEQ/DYN Timing Parameters
Photo courtesy of KA0KA - © 2011
Correct Behringer DEQ2496 DEQ/DYN Timing Parameters
Photo courtesy of KA0KA - © 2011
The Behringer DEQ2496 optimal settings are as follows:
DYN SECTION
The DYN section gives you two options; Downward expansion or compression, but not both at the same time, unfortunately. If you
already have compression available somewhere else separate from the DEQ2496, or you just do not ave any need for traditional compression
(beyond the DEQ section), then use the downward expander. If, on the other hand, you find that you need the compression beyond the DEQ
dynamic control, then use the compressor.
I have used them both. When I was operating the Kenwood TS-850/DSP100, I needed the compressor to prevent high frequency distortion as
a result of the aggressive high frequency EQing I was applying. However, with my current setup using the Apache Labs Anan 7000dle, I find
that I no longer need the compressor to control high frequency tearing. This is because the Anan is much more flat at higher frequencies
and requires much less aggressive eqing. As a result, high frequency distortion does not occur and no compression is needed up there.
NOTES:
The compressor and downward expander sections in the DEQ2496 precede the DEQ section. Therefore, if any changes are made in the DYN section,
the DEQ section must be re-calibrated!
IMPORTANT: You may find that
the numeric values indicated in the following menu's cannot be found on your DEQ2496. This is because you are using the "Coarse"
mode on the knob that selects the values. Simply press the knob IN and a finer resolution will become available.
Downward Expander Section (If not using Compressor)
DYN Page 1 (EXPA Hilighlighted - Black text on Orange background)
Ratio: 1:1.6
DYN Page 2
Attack: 13.18 ms
Release: 49.9 ms
DYN Page 1 again
With NO talking, Adjust "Threshold" so that the "LR GAIN" level reaches -15
When talking, make sure that the "LR GAIN" level recovers to 0.
(
My "Threshold" control ends up at -45dB to make both happen)
Compressor Section (If not using Downward Expander)
DYN Page 1 (COMP Highlighted - Black text on Orange background)
Ratio: 1:2 (Recommended for soft leveling / mild compression) (
user's preference *)
*Dynamic Ratio is user dependent on program material and preference…
Ratios above 20:1 can be classified as soft to hard limiting
Ratios of 4:1 to 6:1 can be classified as soft to hard compression
Ratios of 2:1 or less can be classified as soft leveling to mild compression
DYN Page 2
Attack: 2.77 ms
Knee: 0 (hard) (user's preference)
Release: 85.6 ms
DYN Page 1 again
Make an "EEEEE" sound with your voice and adjust the "Threshold" so that the "LR GAIN" level just starts
to show a slight downward gain reduction (about -1dB).
"SSSing" frequencies should show about -7dB to -10dB of attenuation.
(
My "Threshold" control ends up at -45dB to make this happen)
When adjusted in the manner described above, the compressed high frequencies will allow about another 10dB of headroom in the DEQ #3 section
with high frequency dynamic attenuation. This is because the DYN section precedes the DEQ section, so high frequency compression will occur
before any DEQ processing. This results in excellent high frequency dynamic control!
As an added benefit, 1dB of midrange compression will occur during normal speech and increase at speech levels above normal, while compressing
the high frequencies much more aggressively when needed. (This is because we are EQing much more aggressively at high frequencies and using
a mono-band compressor here.)
Limiter Section
DYN Page 2 (LIMIT MENU)
Hold: 30.6 ms
Threshold: Set to where you want your output peak to be"Clipped" (-3dB recommended)
Release: 304.2 ms
DEQ Section
DEQ #1
DEQ Page 1, DEQ #1
M-Gain: -15dB
Ratio: 1:100
DEQ Page 2, DEQ #1
Attack: 2.77ms
Release: 105.4ms
DEQ Page 3, DEQ #1
Mode: BP
Frequency: 40.4
BW (OCT): 4
DEQ #2
DEQ Page 1, DEQ #2
M-Gain: -15dB
Ratio: 1:100
DEQ Page 2, DEQ #2
Attack: 61.59ms
Release: 50.9ms
DEQ Page 3, DEQ #2
Mode: BP
Frequency: 408
BW (OCT): 5
DEQ #3
DEQ Page 1, DEQ #3
M-Gain: -15dB
Threshold: (Determined with your voice and levels)
Ratio: 1:100
DEQ Page 2, DEQ #3
Attack: .30ms
Threshold: (Determined with your voice and levels)
Release: 20ms
DEQ Page 3, DEQ #3
Mode: BP
Frequency: 10023
BW (OCT): 5
After entering all of the proper parameters, as given above, the individual thresholds for DEQ NO #1 and DEQ
NO #2 should be reset to -5dB of gain reduction while a constant user program is feed into mic. (For example a solid ahhhhh...)
(See example below)
Set DEQ NO #3 to the minimal threshold that eliminates any high frequency distortion.
After this, further adjust the DEQ #3 threshold to a higher negative number for any "SSSing" problem that may be causing
a "Splashy" sound or excessive sibilance in the very high frequencies. Lowering the DEQ #3 threshold effectively accomplishes
"De-Essing" if needed.
Note that any time you readjust your signal levels, re-EQ, or change compression settings anywhere in the chain prior to the
DEQ2496, you MUST recalibrate the DEQ thresholds for all three bands as described above.
The resulting frequency / bandwidth distribution of above parameters:
Note: These three bands control amplitude dynamics, NOT EQing, and is therefore in effect performing independent
"Multi-Band" compression. Even though "Dynamic EQing" uses a different approach than "Multi-Band Compression",
the same resulting dynamic control is achieved.