1 Contents Introduction ...................................................................................................................................3 Features .........................................................................................................................................3 Warnings ....................................................................................................................................4 Description ....................................................................................................................................5 Q-1311 Front Panel Controls ........................................................................................................6 Q-1311 Rear Panel Connections.................................................................................................6 Q-1312V Front Panel Controls .....................................................................................................6 Q-1312V Rear Panel Connections ..............................................................................................6 Q-2312 Front Panel Controls ........................................................................................................7 Q-2312 Rear Panel Connections.................................................................................................7 Q-2151 Front Panel Controls ........................................................................................................7 Q-2151 Rear Panel Connections.................................................................................................7 Q-2152V Front Panel Controls .....................................................................................................8 Q-2152V Rear Panel Connections ..............................................................................................8 Descriptions of Controls ...............................................................................................................8 Front Panel .................................................................................................................................8 Rear Panel ...............................................................................................................................10 Operational Overview ...............................................................................................................11 Installation ...................................................................................................................................12 Available Accessories ...............................................................................................................12 Three Year Limited Warranty .....................................................................................................13 Service .........................................................................................................................................14 Specifications .............................................................................................................................15 2 Introduction Congratulations on your purchase of a Furman Sound Q-Series Graphic Equalizer. You have chosen an instrument which offers outstanding features, superior performance, and unequalled versatility in shaping the tone of your musical, vocal and audio program material. As with all Furman products, the Q-Series Graphic Equalizers are used in highend sound reinforcement, broadcasting, recording, audio for video and film production, DJ systems, musical instrument amplification, and even audiophile home stereo applications. Even if you are an experienced audio professional, please take a few moments to read this brief manual. It will help you get the most out of your Q-Series Equalizer. This manual covers five models: Q-2151: Q-1311: Q-2312: Q-2152V: Q-1312V: Dual 15-band, single rack space Single 31-band, single rack space Dual 31-band, double rack space Dual 15-band, long-throw sliders, VU meters, double rack space Single 31-band, long-throw sliders, VU meter, double rack space Features · · · · · · · · · · Constant-Q response for maximum graphic accuracy. Versatile connectivity via XLR, balanced 1/4" phone, and RCA inputs and outputs. High-performance, detented sliders ISO 1/3 octave (Q-1311, Q-1312V, Q-2312) or 2/3 octave (Q-2151, Q-2152V) frequency bands. Superior common-mode rejection. Heavy-duty, shielded power supply to assure cool and reliable operation. Integrated ground lift for quiet operation. Selectable ±6dB or ±12dB range switches with LED indicators for precision operation. Bypass switch with LED indicator. Overload "Clip" LED warning indicator. 3 · · Output level control. Rugged all steel construction. Warnings Environment Never place this product in an environment that could alter its performance or reduce its service life. Such environments are usually characterized by high levels of heat, dust, moisture, or vibration. Safety 1. Read and follow all instructions carefully. 2. Do not operate this apparatus near water. 3. Clean only with a damp cloth. 4. Install only in accordance with the instructions in this manual. 7. Do not defeat the safety purpose of the polarized or grounding type plug. A polarized plug has two blades, with one wider than the other. A grounding type plug has two blades and a third grounding prong. The wide blade or the third prong is provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet. 8. Protect the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and the point where it is attached to the apparatus. 9. Unplug this apparatus during lightning storms or when unused for long periods of time. For complete protection against lightning strikes and related hazards, a more sophisticated protection device is needed, such as the Furman PRO Series Power Conditioners, or the AR-Series AC Line Voltage Regulators. 10. Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped. 4 Description The Q-2151 is a dual channel 15-band equalizer, using short-throw 20mm sliders and housed in a single rack space chassis. The Q-1311 is a single channel 31-band equalizer, using short-throw 20mm sliders and housed in a single rack space chassis. The Q-2312 is a dual channel 31-band equalizer, using short-throw 20mm sliders and housed in a two rack space chassis. The Q-2152V is a dual channel 15-band equalizer, using long-throw 60mm sliders and a highly accurate VU meter, housed in a two rack space chassis. It is suitable for the most critical applications. The Q-1312V is a single channel 31-band equalizer, using long-throw 60mm sliders and a highly accurate VU meter, housed in a two rack space chassis. It is suitable for the most critical applications. All Q-series equalizers feature precision engineered controls for unparalleled accuracy. The sliders on all units have a smooth, silky feel, with electronically accurate center detents. All 31-band equalizers incorporate high cut control from 3kHz to 40kHz, and low cut control from 10Hz to 250Hz. This extended range offers unequalled control over the extreme ends of the audio spectrum. 5 Q-1311 Front Panel Controls Q-1311 Q-1311 Rear Panel Connections 14 13 12 11 10 Q-1312V Front Panel Controls 9 Q-1312V Q-1312V Rear Panel Connections 14 13 12 11 10 6 Q-2312 Front Panel Controls Q-2312 Q-2312 Rear Panel Connections 14 13 12 11 10 Q-2151 Front Panel Controls Q-2151 Q-2151 Rear Panel Connections 14 13 12 11 10 7 Q-2152V Front Panel Controls 9 9 Q-2152V Q-2152V Rear Panel Connections 14 13 12 11 10 Descriptions of Controls Front Panel 1. POWER SWITCH This switch powers the unit on and off. IMPORTANT: Always turn your equalizer on BEFORE turning on the power amp, and turn the equalizer off AFTER turning off the power amp. For convenience, it is recommended that the equalizer and any other rackmount equipment be powered through a switchable outlet box, such as the Furman PL-8 II Power Conditioner and Light Module. The PL-8 II provides an easy way to power up the entire rack with one front-panel switch, and provides discreet illumination on dark stages and in the studio, as well. If you do use a switchable outlet box, remember to leave the on-off switch in the ON position at all times. 8 2. FREQUENCY SLIDERS Each slider controls the amount of boost or cut to be applied to the associated frequency band, over a range of ±6dB or ±12dB, as selected by the Range Selector. The center detent indicates flat response. In the Q-2151 or Q-2152V, the interval between adjacent slider frequencies is 2/3 octave. In the Q-1311, Q-1312V and Q-2312, the interval between adjacent slider frequencies is 1/3 octave. 3. RANGE SELECTOR and RANGE INDICATORS A range selector switch is provided on all of the Q-Series models, to select a resolution of ±6dB or ±12dB for the EQ sliders. The ±6dB setting allows greater resolution in situations where large amounts of boost or cut are not needed. A yellow light indicates a boost and cut of +12 dB; a green light indicates a boost and cut of + 6 dB. 4. BYPASS SWITCH and INDICATOR The Bypass Switch is useful for quick comparison of the original sound with EQ'ed sound, allowing the equalization signal to be bypassed for a quick "before and after" comparison of the EQ effects. When the Bypass LED is lit the EQ is in bypass mode. The stereo Q-2151, Q-2152V, and Q-2312 have two of these buttons allowing either channel to be bypassed independently. Note that when the Bypass button is activated, the Level Control is bypassed as well. 5. OVERLOAD INDICATOR This LED lights if any of the equalizer's circuitry approaches 5dB before clipping. Occasional blinking of this indicator is acceptable, but if it lights continuously it is necessary to reduce the input level, frequency boost, or the output level. 6. LOW CUT CONTROL (Q-1311, Q-1312V, and Q-2312 only) Most audio systems cannot reproduce subsonic sounds, nor can the human ear hear them. Yet they are often present in audio signals. If allowed to reach power amplifiers or recording devices, they can rob power and cause distortion while adding little, if anything, to sound quality. The Low Cut knob allows the cutoff frequency to be set anywhere in the range of 10Hz to 250Hz. This also makes it useful for the removal of some types of RFinduced hum. Roll off beyond the cutoff point is at 12 dB per octave. 7. HIGH CUT CONTROLS (Q-1311, Q-1312V, and Q-2312 only) Most audio systems cannot reproduce supersonic sounds, nor can the human ear hear them. Yet they are often present in audio signals. If allowed to reach power 9 amplifiers or recording devices, they can rob power and cause distortion while adding little, if anything, to sound quality. The High Cut's range is 3KHz to 40 KHz. Roll off beyond the cutoff point is at 12 dB per octave. 8. LEVEL CONTROL Adjusts the overall output volume. The combined effect of the EQ Frequency sliders typically results in an increase or decrease of overall output level. The Level Control can compensate for this change in level. Compare the level of the equalized signal with that of the unequalized signal (bypass button in), and use the Level Control to eliminate any difference in levels. 9. LEVEL METERS (Q-2152V, Q-1312V) Each channel of the EQ is equipped with a backlit VU meter. The meter is calibrated for "0" level equal to +4 dBu output. Rear Panel 10. POWER CABLE This cable is used to connect to an AC power source. For North American models, this source shall be 115 115VAC; for export models, the source shall be 230VAC. 11. FUSE HOLDER This holder contains the AC primary fuse. If the fuse has blown, replace with the same size and rating. If the fuse continues to blow, refer servicing to qualified technical personnel. 12. AC VOLTAGE SELECTOR Set this switch to match the AC line voltage in your area. 13. GROUND LIFT SWITCH In many installations, hum-causing ground loops are formed by the common connection of various pieces of equipment to the power line ground, and by contact between chassis, as in a rack with metal rails. Sliding the Ground Lift switch up completely isolates all signal grounds from the chassis, breaking any ground loops. The chassis always remains connected to the ground pin on the AC cord for safety and to shield against RF interference. Try both positions of the Ground Lift switch, and leave the switch in the position that results in the least hum in your system. Note: The ground lift can be rendered ineffective by ...