User manual BEHRINGER PEQ2200

[. . . ] PEQ2200 Users Manual Version 1. 2 September 2001 ULTRA-Q PRO ® www. behringer. com ENGLISH ULTRA-Q PRO PEQ2200 SAFETY INSTRUCTIONS CAUTION: To reduce the risk of electric shock, do not remove the cover (or back). No user serviceable parts inside; refer servicing to qualified personnel. WARNING: To reduce the risk of fire or electric shock, do not expose this appliance to rain or moisture. This symbol, wherever it appears, alerts you to the presence of uninsulated dangerous voltage inside the enclosurevoltage that may be sufficient to constitute a risk of shock. This symbol, wherever it appears, alerts you to important operating and maintenance instructions in the accompanying literature. [. . . ] Turn the BANDWIDTH control counter-clockwise to adjust the minimum quality of 0. 03 octaves, and clockwise to adjust the maximum bandwidth. Turn the LEVEL control clockwise to raise, or counter-clockwise to lower the filter amplitude. The FREQUENCY control works on the same principle. 5. TECHNICAL BACKGROUND 11 ULTRA-Q PRO PEQ2200 Fig. 5. 1: Various filter qualities During operation you can switch on and off the individual bands to make an A/B comparison between the equalizer effect and the unprocessed signal. Due to the complex and partly difficult settings of parametric equalizers such a facility is indispensable. Still, most parametric EQs have no band-specific in/out switches which makes it difficult to keep track of what the various switches and controls do. 5. 2 The Constant-Q principle One of the most important features any graphic or parametric equalizer has to offer is the independent control of its various parameters. The special state-variable filters of the ULTRA-Q PROs use the so-called Constant Q principle which prevents the parameters frequency, bandwidth and amplitude from influencing each other. In the same way, the mutual influence of the individual frequency bands is avoided, which is a fundamental requirement as it allows for clearly defined and repeatable filter settings. When several filters are used simultaneously, the resulting overall filter curve can be calculated by adding/subtracting the single band-specific filter curves. 5. 3 The concept of parallel filters Unlike conventional parametric equalizers the ULTRA-Q PRO features a parallel filter configuration, which offers a decisive advantage over series-type configurations: with parallel filters it is possible to reduce to a minimum the phase shifts and delays usually associated with filters, which is the reason why the ULTRA-Q PRO is such a musical device. Naturally, this concept, too, is subject to a few limitations: unlike series-type filter configurations the concept of parallel filters allows only to a limited extent for an extreme boost/cut of frequencies. However, as extreme settings are usually the result of an improperly adjusted sound image, it is imperative that deficiencies of this kind be identified and eliminated, before the actual musical fine-tuning of the sound image takes place. Still, extreme settings can be realized by overlapping the frequencies of the individual bands. 5. 4 Filter functions 5. 4. 1 The notch function With notching or peaking we describe the specific attenuation of single frequencies or frequency bands. A notch filter produces an effect that is the opposite to a band-pass filter. 12 5. TECHNICAL BACKGROUND ULTRA-Q PRO PEQ2200 Fig. 5. 2: Typical notch function 5. 4. 2 The roll-off function With roll-off we usually refer to a limitation of frequency bands by means of high or low-pass filters. The low and high-cut filters on the ULTRA-Q PRO have a slope of 12 dB/oct. and can be varied within a wide frequency range. Fig. APPLICATIONS 6. 1 Introduction and basic settings In contrast to graphic equalizers with their fixed frequencies and qualities, parametric EQs allow for setting all filter parameters, such as center frequency, bandwidth and amplitude. The possibility of determining both the bandwidth and center frequency as well as frequency boost/cut in five separate bands, adds a new dimension to equalization systems. The high precision of the filters used in the ULTRA-Q PRO enables you to fine-tune frequencies and process your audio material in a such a creative way that has been impossible up to now. The frequency bands are grouped so as to cover the entire audio range from 20 Hz to 20 kHz, with the frequency ranges of the single bands overlapping each other. [. . . ] This also applies to defects caused by normal wear and tear, in particular, of faders, potentiometers, keys/buttons and similar parts. Damages/defects caused by the following conditions are not covered by this warranty: s misuse, neglect or failure to operate the unit in compliance with the instructions given in BEHRINGER user or service manuals. s connection or operation of the unit in any way that does not comply with the technical or safety regulations applicable in the country where the product is used. s damages/defects caused by force majeure or any other condition that is beyond the control of BEHRINGER. [. . . ]