User manual ART XL231

[. . . ] OPERATION MANUAL ART XL 231 Dual 31 Band, 1/3 Octave Extended, Long Throw, Professional Equalizer IMPORTANT SAFETY INSTRUCTION ­ READ FIRST This symbol, whenever it appears, alerts you to the presence of uninsulated dangerous voltage inside the enclosure that may be sufficient to constitute a risk of shock. This symbol, wherever it appears alerts you to important operating and maintenance voltage instructions in the accompanying literature. Read instructions: Retain these safety and operating instructions for future reference. Heed all warnings printed here and on the equipment. [. . . ] When balanced, the tip is High (+), the ring is Low (-) and the sleeve is ground. To use unbalanced use a mono ¼" phone cable, this will automatically ground the ring to the sleeve. The TRS ¼" Phone connector is balanced and wired as: Tip = High (+) Ring = Low (-) Sleeve = Ground. XLR The XLR input connector is balanced and wired as: Pin 2=High (+) Pin 3=Low (-) Pin 1=Ground. EURO BLOCK The detachable Euroblock connections are wired as shown on the rear panel. 11 ART XL 231 Dual 31 Band, 1/3 Octave Extended, Long Throw, Professional Equalizer APPLICATION NOTES Graphic equalizers may be used wherever modification of the frequency contour of a sound system is needed. A graphic equalizer is a solution to any number of sound problems or creative urges. The Audio Spectrum, a Reference In general, what we hear extends over a range of frequencies from 20 Hertz (Hz) to 20 Kilohertz (KHz). This equates to roughly ten and one third octaves, an octave being a factor of two. The most perceived range lies between 300Hz to 3KHz, the region where most voice information occurs. The audio spectrum may be divided into seven frequency ranges. We will define these ranges in the following text. Low Bass: 20Hz to 40Hz This is the lowest of normally audible octaves. Below these frequencies, sounds are more felt than heard. These subaudible frequencies are produced by earthquakes, building vibrations, elephants and huge organ pipes. Low bass information include the fundamental frequencies of the lowest keys on organs, synthesizers and pianos. Mechanical rumble also falls within the range below 40Hz. These low bands on the equalizer may be useful for tailoring the low frequency response of some speakers and microphones. Bass: 40Hz to 160Hz These two octaves are normally perceived as the bass frequencies. Instruments such as the electric and string bass, tuba, bass drum and the lower notes of keyboard instruments fall within this range. The bottom end of most music is reflected here. Mid Bass: 160Hz to 315Hz In this octave, the transition between bass and midrange occurs. Low frequency crossover points in speaker systems are usually selected in this range. [. . . ] 10 to 250 Hz ­ 12dB/Oct ± 4 dB @ 10 KHz ± 4 dB @ 40 Hz [EQ and Level centered, HPF fully counter clockwise] (+0/-0. 25 dB 20-20K Hz), (+0/-1 dB 17-50K Hz), (+0/-3 dB 10-80K Hz) < 0. 005%, @ +4 dBu, 20-20K Hz, 22 KHz BW, [EQ and Level centered] < 0. 004%, @ +4 dBu, [EQ and Level centered] 99 dB, Ref. 0 dBu, 22 KHz BW, unweighted, [EQ and Level centered] +24 dB, Ref. 0 dBu 123 dB, Ref: +24 dBu, 22 KHz BW 90 dB @ 1 KHz, +4 dBu 60 dB @ 1 KHz 95-125 VAC 50/60 Hz 190-250 VAC 50/60 Hz 31 Watts Typical All Steel Chassis Aluminum Front Panel 5. 25 x 19 x 8 Inches 133 x 483 x 203 mm 12 lbs. (5. 4 kg) 18 ART XL 231 Dual 31 Band, 1/3 Octave Extended, Long Throw, Professional Equalizer XL231 Architect's & Engineer's Specification The graphic equalizer shall be stereo (2 channels). [. . . ]