Behringer MX9000 user manual Equalization

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9. EQUALIZATION

The variable parameters of the channel A and B equalizers on the EURODESK MX9000 are described in sections 3.4 and 3.7.

Few people buying the EURODESK will need to be told how an equalizer works. But how to get the best out of it? Well, that’s another story.

In the beginning EQ was an instrument for removing unwanted frequencies, or compensating for imperfect microphone response curves, or bumps in a studio’s acoustic. It was a corrective device. Tamla Motown turned that notion upside down in the sixties with the novel idea that you try to find for each instrument a characteristic frequency not shared by the other instruments in the mix. Then you whack up it’s gain. This makes individual voices punch through a mix in a slightly unnatural but exciting way. In general, corrective EQ usually involves broadband (slope) contouring, together with narrowband notching of unwanted resonances. The narrower the notch or “Q”, the less the total signal will be affected.

+Finding bad resonances is made easier by first frequency sweeping in boost mode.

“Motown” EQ is achieved by applying boost in a fairly broadband way. The broader the band, the more musical but less instrument-specific the effect. Applying boost over a narrow bandwidth will sound “Honky”. The two semi-parametric bands of the EURODESK EQ have had their Q fixed at 1, a typical and sensible value. For sounds which require drastic corrective EQ (remember no MIDI instrument should need it), it is advisable to have a couple of channels of fully comprehensive equalization in your rack. (You can always bounce tracks though the outboard EQ, freeing up the unit for the next task). Check out our BEHRINGER ULTRA-CURVE PRO DSP8024, which promises to be another price/performance buster.

The EURODESK EQ might be applied to a signal as follows: First, trim the LF and HF shelves to achieve the required slope or “LOUDNESS”. (These controls mirror the tone controls of a typical HiFi amp.) Now use one parametric band to boost the nicest frequency, and another to cut the nastiest. Over all channels in the mix, if too many of the nicest frequencies coincide, then you might have to settle for second best in some cases! Often you might want to boost two nice frequencies. Really nasty frequencies will need notching. Time to go outboard.

Why does the upper mid bell frequency go up to 20 kHz? A more pertinent question might be, why has it taken so long to get there? After all, even 16 bit (the lowest acceptable quality) digital audio sports a 20k bandwidth: surely if 20k is important then so is controlling it. OK. You and I will never hear a pure 20k sine tone. However, Rupert Neve, the audiophile Guru, would argue that when it comes to real instruments, what happens even above 20k may have a perceptible effect on the listener. It seems that one reason why high- quality (1/2" at 30 IPS) analog tape sounds better than DAT to many discerning ears is because, although it’s frequency response begins to roll off at 12 dB/octave somewhere around 15 to 20 kHz, it is not abruptly cut off at 20!

We have heard, or “detected”, a 20+ kHz low pass filter being switched in and out when monitoring an analog master tape through a speaker system that included piezo-electric tweeter elements capable of reproducing up to 40 kHz. Perhaps less controversially it can be shown that if cut/boost is applied at 20 kHz, a significant portion of the resulting EQ curve for all but the tightest of Q’s actually occurs in the audible spectrum, below 16 to 18 kHz. For example if the BEHRINGER EQ is boosted by +15 dB at 20 kHz, the amount of boost at 10 kHz will be 3 dB. The resulting EQ curve will bear no relation to one where 3 dB of boost is applied at 10 kHz.

+A good vocal signal can be enhanced by applying a significant boost in the 15 k region or higher, above the nasty sibilance region. Especially effective if you’ve got a de-esser post EQ.

+Use the LF cut to tighten up channels in a mix: maybe remove it only for the bass, kick drum, toms, tablas, didgeridu and other deliberate subsonics. (When recording classical music ignore this advice).

+With an LF cut at 100 Hz and a lo sheelf boost at 80 to 160 Hz, you have pretty much got a peak response rather than shelving at the bottom.

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Contents Eurodesk MX9000 Detailed Safety Instructions Safety InstructionsForeword Table of Content Track Recording with 2 Samplers Eurodesk Overview ManualMetering PSU Power Supply UnitInput switching INPUT/OUTPUT ChannelChannel strip Channel input switching architecture Input gain settingAux sends Main equalizerAux sends Routing and mutingRouting ChannelB-channel InsertsSubgroups Subgroup and Direct OutputsStereo subgroup channel schematic Master Panel Direct outputsAux masters Aux sends Stereo aux returns Mix-B MIX-B masterMonitoring MonitoringPhones HeadphonesTalkback PFL/SOLORear panel ConnectionsPower supply unit connector Subgroup inserts Main balanced outputs 10 MIX-B operating level switch and phantom power switch Plug soldering guide Page Patchfield Normalized bayPatchfield Example of patchbay configurations Wiring for bay 8 for advanced wiring scheme refer to section Looming problemsEqualization Gain Optimization Unbalanced Lines Impedances and TuningSTART-UP Channel setting up procedureDesk/tape setting up procedures Track Midi SUITE/DANCE Production Studio Sends Auxless headphones mixReturns Slightly more complicated auxless headphones mixLining up record/sample inputs Track Recording with 2 SamplersMixdown RecordingProfessional 24-TRACK Studio HeadphonesTab .1 Channel assignment Very tricky headphones Live P.A. with 2-TRACK RecordingWet monitoring Tab .1 Channel assignments 2-track Live Concert with 24-TRACK Recording Tab .2 Front/rear/stage monitors routing Timecode Expanding the Eurodesk MX9000Connections AlignmentSequencing Live BouncingModifications INPUT/OUTPUT ConfigurationAux sends post EQ MIX-B source post faderLED meters pre fader Specifications DBr ref. +4 dBu, 24 chs. assigned input B & set @ unity gain § 1 Warranty CARD/ONLINE Registration WarrantyPage
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