286A - Receiver DBX - Free user manual and instructions

USER MANUAL 286A DBX

Mic Preamp/ Processor 286A

Owner/Operator Manual Manuel d’utilisation Bedienungsanleitung Manual de instruccionesWARNING FOR YOUR PR OTECTION, READ THESE INSTRUCTIONS: WATER AND MOISTURE: Appliance should not be used near water (e.g. near a bath- tub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool,etc). Care should be taken so that objects do not fall and liquids are not spilled intothe enclosure through openings. POWER SOURCES: The appliance should be connected to a power supply only of the type described in the operating instructions or as marked on the appliance. GROUNDING OR POLARIZATION: Precautions should be taken so that the ground- ing or polarization means of an appliance is not defeated. POWER CORD PROTECTION: Power supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against them, payingparticular attention to cords at plugs, convenience receptacles, and the point wherethey exit from the appliance. SERVICING: To reduce the risk of fire or electric shock, the user should not attempt to service the appliance beyond that described in the operating instructions. All otherservicing should be referred to qualified service personnel.FOR UNITS EQUIPPED WITH EXTERNALLY ACCESSIBLE FUSE RECEPTACLE:Replace fuse with same type and rating only. MULTIPLE-INPUT VOLTAGE: This equipment may require the use of a different line cord, attachment plug, or both, depending on the available power source at installa-tion. Connect this equipment only to the power source indicated on the equipment rearpanel. To reduce the risk of fire or electric shock, refer servicing to qualified servicepersonnel or equivalent. SAFETY INSTRUCTIONS NOTICE FOR CUSTOMERS IF YOUR UNIT IS EQUIPPED WITH A POWERCORD.

WARNING: THIS APPLIANCE MUST BE EARTHED.

The cores in the mains lead are coloured in accordance with the following code:GREEN and YELLOW - Earth BLUE - Neutral BROWN - LiveAs colours of the cores in the mains lead of this appliance may not correspondwith the coloured markings identifying the terminals in your plug, proceed as fol-lows:• The core which is coloured green and yellow must be connected to theterminal in the plug marked with the letter E, or with the earth symbol, orcoloured green, or green and yellow.• The core which is coloured blue must be connected to the terminalmarked N or coloured black.• The core which is coloured brown must be connected to the terminalmarked L or coloured red.This equipment may require the use of a different line cord, attachment plug, orboth, depending on the available power source at installation. If the attachmentplug needs to be changed, refer servicing to qualified service personnel whoshould refer to the table below. The green/yellow wire shall be connected direct-ly to the unit's chassis.

WARNING: If the ground is defeated, certain fault conditions in the unit or in the

system to which it is connected can result in full line voltage between chassisand earth ground. Severe injury or death can then result if the chassis andearth ground are touched simultaneously. LIVE

A moulded mains plug that has been cut off from the cord is unsafe. Discard themains plug at a suitable disposal facility. NEVER UNDER ANY CIRCUM-STANCES SHOULD YOU INSERT A DAMAGED OR CUT MAINS PLUG INTOA 13 AMP POWER SOCKET. Do not use the mains plug without the fuse coverin place. Replacement fuse covers can be obtained from your local retailer.Replacement fuses are 13 amps and MUST be ASTA approved to BS1362.The symbols shown above are internationally accepted symbols that warn ofpotential hazards with electrical products. The lightning flash with arrowpoint inan equilateral triangle means that there are dangerous voltages present withinthe unit. The exclamation point in an equilateral triangle indicates that it is nec-essary for the user to refer to the owner’s manual.These symbols warn that there are no user serviceable parts inside the unit.Do not open the unit. Do not attempt to service the unit yourself. Refer all ser-vicing to qualified personnel. Opening the chassis for any reason will void themanufacturer’s warranty. Do not get the unit wet. If liquid is spilled on the unit,shut it off immediately and take it to a dealer for service. Disconnect the unitduring storms to prevent damage. CAUTION ATTENTION: RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR

WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC

SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURERISK OF ELECTRIC SHOCKDO NOT OPEN ELECTROMAGNETIC COMPATIBILITY This unit conforms to the Product Specifications noted on the Declaration ofConformity. Operation is subject to the following two conditions:• this device may not cause harmful interference, and • this device must accept any interference received, including interferencethat may cause undesired operation.Operation of this unit within significant electromagnetic fields should be avoided.• use only shielded interconnecting cables.

DECLARATION OF CONFORMITY

Manufacturer’s Name: dbx Professional Products Manufacturer’s Address: 8760 S. Sandy Parkway Sandy, Utah 84070, USA declares that the product: dbx 286A conforms to the following Product Specifications: Safety: EN 60065 (1993) IEC65 (1985) with Amendments 1, 2, 3 EMC: EN 55013 (1990) EN 55020 (1991) Supplementary Information: The product herewith complies with the requirements of the Low Voltage Directive 73/23/EEC and the EMC Directive 89/336/EEC as amended by Directive 93/68/EEC. dbx Professional Products President of dbx 8760 S. Sandy Parkway Sandy, Utah 84070, USA June 23, 2003 European Contact: Your Local dbx Sales and Service Office orMic Preamp/ Processor 286A

Front Panel Input Congratulations on choosing the dbx 286A Mic Preamp/Processor. The 286A is apowerful, user-friendly unit, providing concise and intuitive controls for all your micprocessing needs, whether you use a microphone to record vocals and acoustic instru-ments, sample acoustic sounds, or for a public address system installation. The 286Ais also capable of providing effective processing for electronic instruments, individ-ual mixer tracks, and other mono sound sources.You can think of the 286A as two separate processors, a Mic Preamp Section and aProcessing Section. These two sections can be used together, or the 286A can beused as a dedicated Mic Preamp by defeating the Processing Section via the frontpanel BYPASS switch. Furthermore, the Processing Section provides four specifictypes of processing: Compression, De-essing, Enhancement and Expansion/Gating.These four controls can be used in any combination, as appropriate to your require-ments. External audio processors (e.g., equalizer, delay unit, etc.), can be placed inthe signal chain directly between the Mic Preamp Section and remaining 286A pro-cessing via the rear panel INSERT jack. We recommend that you take a moment andread through the 286A manual to better understand the power of the 286A’s process-ing, and how you can use the 286A to its fullest potential.Note: To reduce the risk of damage to your system, set the MIC GAIN control fully counterclockwise andlower your playback monitor levels before you connect a microphone, power on the unit, or press thePHANTOM button. This will eliminate spikes and surges, acoustical feedback, loud pops, momentary hiss,or other unwanted sounds.MIC GAIN (dB) and LEVEL (dBu) LEDs (including CLIP LED): Use this con-trol to set the level of gain added to the microphone input signal (or a line-levelinput). Note that the 286A’s processing controls, or an external processor connectedto the 286A’s INSERT, can provide additional gain. Try to set the MIC GAIN con-trol so that you do no have to reset it repeatedly; allow headroom for the maximumexpected levels. For microphones (connected to the XLR MIC INPUT connector),the 286A can provide +10dB to +60dB of input gain. For line-level inputs (connect-ed to the LINE INPUT jack), the gain is from -20dB to +30dB. Note: To get the lowest noise possible from the 286A, set the input attenuators (if any) on your recorder or mixer for nominal levels (often about 3/4” of the way up or at the detent position; refer to the device’s oper- ating manual). Then, set the 286A MIC GAIN so that your recorder or mixer is at its optimal operatinglevel.The red CLIP LED (located to the left of the MIC GAIN control) indicates that thecombination of the mic signal and additional gain exceeds the circuit’s capabilities;reduce gain via the MIC GAIN control. Set the MIC GAIN control so that the CLIPLED never lights.The LEVEL LEDs can also be used to check the strength of the input signal. Forexample, the 286A does not support low level microphones plugged into its 1/4”INPUT jack; in this case, the LEVEL LEDs would not light, because the signal is too low. INTRODUCTION OPERATING CONTROLSMic Preamp/ Processor 286A

Mic Preamp/ Processor 286A Bypass Compressor PHANTOM POWER Button and LED: When you use phantom powered mics with your 286A, press the PHANTOM POWER button In to activate the 286A’s phantom power, providing +48VDC to the microphone through its connecting cable. This industry-standard configuration supports virtually all currently-manufactured phantom power mics. If you do encounter problems, it will typically be with an older mic. Note that some mics may take several seconds to fully power up when phantom power is applied. If you are using mics that do not require phantom power, press the button so that it is in the Out position. Note: Always plug in a condenser mic with PHANTOM POWER Off and gain levels down. Then switch thePHANTOM POWER On and adjust the gain as needed. The yellow PHANTOM POWER LED lights when the PHANTOM POWER button is in. HIGHPASS (80Hz) Button and LED: Press this button In to activate the 286A’s pre-processing third order filter. The HIGHPASS function filters out frequencies below 80Hz by 18dB/octave before any compression, de-essing, etc., is applied to input signal. This is most effective for reducing hum, rumble, wind and other low frequency problems. The HIGHPASS filter is also before any external processing provided via the rear panel INSERT jack. The HIGHPASS LED lights when the HIGHPASS button is In. PROCESS BYPASS Button and LED: Press this button In to bypass the 286A Compressor, De-Esser, Enhancer, and Expander/Gate processing circuitry and the OUTPUT GAIN control (as well as any processing provided by external processors via the rear panel INSERT jack). In Bypass mode, the 286A will apply gain and fil- tering as set with Mic Preamp Section controls. BYPASS is equivalent to setting the 286A’s Compressor DRIVE, De-Esser THRESHOLD, Enchancer LF and HF DETAIL and Expander/Gate THRESHOLD controls to OFF, the OUTPUT GAIN control to 0dB (12:00 position), and not connecting any external processing to the rear panel INSERT jack. Bypass is especially useful for making comparisons between processed and unprocessed signals. The red PROCESS BYPASS LED lights when the PROCESS BYPASS button is pressed In. Note: The Compressor is Off when the DRIVE is set to OFF. DRIVE Control: The DRIVE control determines the overall amount of gain reduction by setting the signal level going into the gain control circuitry. Turning DRIVE clockwise will increase the input signal, and therefore increase the amount of applied gain reduction. Turning DRIVE fully counterclockwise (to OFF) allows the com- pressor to pass all signals unattenuated, effectively bypassing the compressor. Higher DRIVE settings can cause the Compressor Section to add substantial gain to signal, especially with low input levels. For example, setting the DRIVE control to 12:00 can add up to 20dB of gain to low signal levels. With hotter input levels going into the Compressor Section (whether from the MIC INPUT, LINE INPUT or INSERT jacks), gain addition due to the DRIVE control will be less noticeable. DENSITY Control: Use this control so speed up or slow down the program-depen- dent release times. The scale is arbitrary because the release time is automatically varied according to the nature of the program material (to minimize audible compres- sion-induced side effects). The release rate is from 0 (a slow release for smooth com- 3Mic Preamp/ Processor 286A

De-Esser Enhancer Expander/Gate pression) to 10 (a fast release where compression follows the envelope of the pro- gram very tightly). There is no absolute “right” way to set the DENSITY control. However, in general, slower settings are useful for gating out noise present behind vocals and acoustic instruments, while faster settings are useful for tightening up the sound of percussion instruments (e.g., a kick or snare drum). GAIN REDUCTION (dB) Meter: This meter shows the true peak gain reduction in dB. If the red LED at the far left of the meter lights, no further gain reduction is available. FREQUENCY Control: Use the control to set the HIGHPASS frequency of the vari- able filter used in the De-Esser circuitry. Settings between 4-8kHz will yield the best results for vocal processing, while more extreme settings allow the 286A to be used in other non-vocal applications. THRESHOLD Control: Use this control to set the sensitivity of the De-Esser as a percentage of the average program level at the 286A’s input. This means that the De- Esser tracks the input level so the amount of de-essing remains constant with changes in input level. The De-Esser 1dB and 6dB THRESHOLD LEDs light when the De-Esser is active. These indicate (in dB) how much sibilance reduction is occurring due to the De- Esser. Note: The low and high frequency enhancers are off when their respective DETAIL controls are set to OFF. LF DETAIL Control: The 286A’s Low Frequency enhancement simultaneously applies an 80Hz boost and 250Hz cut to the program. This lets you apply substantial bass boost without making the program sound muddy or boomy due to excessive mid-bass boost. HF DETAIL Control: This control determines the amount of High Frequency spec- tral-enhanced signal added to the input signal. Spectral Enhancement is a form of dynamic phase and amplitude equalization. Continuous analysis of the input signal intelligently and automatically determines the amount of equalization necessary at each moment to achieve detailed, defined audio that is never shrill or over-sibilant. Note: The Expander/Gate is off when the Expander/Gate THRESHOLD is set to OFF. THRESHOLD (dB) Control and LEDs: Adjusting this control sets the level at which the expander/gate will fully open and allow the signal at the input to pass through to the output. Turing the knob fully counterclockwise (to OFF) allows the gate to pass all signals unattenuated, effectively bypassing the gate. Turning the knob fully clockwise causes the gate to attenaute input signals below approximately +15dBu. The amount of attenaution depends on the setting of the Expander/Gate’s EXPANSION RATIO. The THRESHOLD (-) LED (located to the right of the EXPANSION RATIO control) lights when the signal is below the set THRESHOLD. The THRESHOLD (+) LED lights when the signal is above the set THRESHOLD. The combination of these two LEDs also serves as the “POWER ON” function, as one or the other is always on. EXPANSION RATIO Control: This control sets the amount of attenuation applied to the input signal once it is below the threshold, from gentle downward expansion (appropriate for mixed program, vocals, etc.), to a hard gating effect (effective forMic Preamp/ Processor 286A

Output Rear Panel percussion). Fairly low EXPANSION RATIO settings (and higher Expander/GateTHRESHOLDs) work best for downward expansion, whereas higher EXPANSIONRATIO settings (clockwise towards 10:1) work best for gating. If a setting producesundesirable “pumping” readjust the Expander/Gate EXPANSION RATIO andTHRESHOLD settings.Note: The attack and release rate of the Expander/Gate are program-dependent -- very fast for transientmaterial (e.g., percussion) and slower for material with slow attack (e.g., vocals).Readjust as needed to gate out noise -- external, as well as hiss from the unit. The286A’s other processing can add substantial gain to a signal, especially at higher set-tings, thereby increasing the noise floor. GAIN (dB) Control and CLIP LED: The OUTPUT GAIN control sets the level at the line output. The OUTPUT GAIN control is especially useful to compensate forthe RMS level changes which result from the 286A’s processing effects. For exam-ple, to decrease the overall gain (e.g., when the 286A’s processing has added toomuch gain), simply turn the OUTPUT GAIN control counterclockwise. The OUT-PUT GAIN can also be used to counter any gain reduction after you have adjustedthe 286A’s controls for the desired amount of processing; adjust the OUTPUT GAINcontrol clockwise, to add gain as needed.The red OUTPUT GAIN LED (located to the right of the OUTPUT GAIN control)lights when the 286A Processing Section is clipping; reduce gain via the OUTPUTGAIN control. Set this control so that the OUTPUT CLIP LED never lights. If theOUTPUT CLIP LED is still lit, reduce the gain caused by the 286A’s processors (e.g.,high Compressor DRIVE settings) or the gain provided by an external processor con-nected to the INSERT (if any).If the meters on your load device (e.g., tape recorder, mixer, etc.) are in the red andyour OUTPUT CLIP LED is not lit, simply reduce the 286A’s OUTPUT GAIN untilthe desired levels are obtained. If your load device is still in the red, reduce its inputattenuators (if available). MIC INPUT Jack: The 286A’s MIC INPUT jack supports professional and home studio microphones by accepting either balanced or unbalanced signal through anXLR connector. Pins 2 and 3 are symmetrically balanced and floating; thus, eithercan be used as “HOT” without difficulty. Pin 2 is in phase with the TIP of all 1/4”connectors. Pin 1 is connected to the 286A’s chassis ground.Note: Use a low impedance mic or a high-to-low impedance matching transformer with a high impedance mic. LINE INPUT Jack: Use a 1/4” TRS phone plug to connect line level sources to the 286A (e.g., mixer outputs, effects loops, electronic keyboards, etc.). The 286A’sLINE INPUT jack accepts either balanced or unbalanced signals. Input impedance is30kΩ unbalanced, 60kΩ balanced.Note: In general, this jack does not support microphones with 1/4” plugs. Use an appropriate 1/4”-to-XLRadapter and plug the microphone into the MIC INPUT jack. 5Mic Preamp/ Processor 286A

LINE OUTPUT Jack: The 286A’s LINE OUTPUT jack accepts either balanced or unbalanced 1/4” phone plugs. Nominal output signal levels is 0dBu into 600Ω, and maximum output signal level is >+21dBu into 600Ω. Output impedance is 100Ω unbalanced, 200Ω balanced. The output is tip HOT. INSERT Jack: The 286A INSERT jack allows you to either add an effects loop directly into the 286A circuitry chain or take a separate mic preamp signal out.To connect one or more external processors or effects devices (e.g., an equalizer,delay unit, etc.) between the Mic Preamp Section and the Processing Section, insert a1/4” TRS plug carrying the external device’s output signal fully into the 286A’s INSERT jack; the TIP acts as a Send, carrying the signal from the Mic Preamp Section at an impedance of 100Ω, while the RING acts as a Return for external devices to feed the 286A’s processing circuitry (i.e., 286A’s compressor, de-esser,etc.). This operation requires a Y-cable. When using INSERT as a direct in to theProcessing Section, MIC GAIN control, HIGHPASS button and PHANTOMPOWER will not be active.To use the INSERT jack to MULT the preamp out (i.e., to provide an output with abuffered version of the signal after the Mic Preamp circuitry, but before theProcessing Section), insert a Mono 1/4” plug fully into the INSERT jack, then pullthe plug out one click. Plug the other end of the cable to the appropriate load. Thiswill still allow the original signal path to continue to the Processing Section withoutinterruption.Note: If the plug is accidentally pushed fully into the INSERT jack, it will break off the connection betweenthe Mic Preamp and Processing Sections; in this case, there would be no signal at the 286A’s LINE OUT-PUT jack. AC Power: Connect the AC power cord to the AC receptacle on the back of the unit. Route the AC power cord to a convenient power outlet away from audio lines. Theunit may be turned on and off from a master equipment power switch.The 286A can be used with any low-level microphone signal (via the MIC INPUT) orany line-level device (via the LINE INPUT). Some common line-level devicesinclude: mixing consoles, electronic musical instruments, patch bays, and signalprocessors. For all connections, refer to the following steps:1. Turn Off all equipment before making any connections.2. Mount the 286A in a rack. (Optional)Caution: Never remove the cover. There are no user-serviceable parts inside.The 286A requires one rack space (height) and one rack space (width). It can bemounted above or below anything that doesn’t generate excessive heat, since itrequires no special ventilation. Ambient temperature should not exceed 113°F(45°C) when equipment is powered.3. Make connections via rear panel jacks and connectors according to yourrequirements.A. Connect a microphone to the MIC INPUT XLR connector or a linelevel source to the 1/4” LINE INPUT jack.Important: DO NOT connect anything other than a microphone to the MIC INPUT.B. Connect the load (e.g., mixer, tape recorder, etc.) to the 286A’s LINE

CONNECTING THE 286A TO YOUR SYSTEM

Basic ConnectionMic Preamp/ Processor 286A

Using the Mic Preamp Alone(i.e., Using the 286A as aDedicated Mic Preamp)Processing SectionCompressorOUTPUT jack.C. Connect an external processor or effects device to the 1/4” INSERTjack. (Optional)4. Connect the AC power cord to the AC power receptacle on the back of the unit.Note: We recommend you always power on the unit with the MIC GAIN control set to its minimum level(fully counterclockwise). This will help in safeguarding your system against sudden spikes and surges, aswell as possible acoustical feedback if a microphone is connected and left “open.”Note: Check the line voltage (printed on 286A) and verify that it is correct.The 286A’s Mic Preamplification Section includes support for phantom-poweredmics, a highpass filter, and an input gain control. Note that these controls are appliedto the input signal before the signal is processed by the 286A’s Processing Section.Phantom power is available at the push of a button, providing +48VDC to phantom-powered microphones. The 286A’s phantom power is sufficient for most micro-phones, However, some vintage condenser mics may require a separate powersource.Press the HIGHPASS button In to cut signals below 80Hz by 18dB/octave, effective-ly filtering out mic proximity effects, hum, rumble, wind and other low frequency“undesirables.”Use the MIC GAIN control to achieve the best definition and character possible fromyour microphone. The 286A’s Mic Preamp delivers up to 60dB of sonically transpar-ent gain to reveal the detail and audio signature of even the most esoteric mics. Ittransforms their low level output signal to a high level, high current signal that isinternally fed to the 286A’s main processing chain (i.e., compressor, de-esser, etc.)To use the 286A as a dedicated mic preamp, simply press the BYPASS button todefeat the Processing Section circuitry. This allows you to use the Mic preamp’sPHANTOM POWER switch, HIGHPASS button and MIC GAIN control withoutrouting the signal through any of the processing circuitry.The 286A’s Processing Section consists of four specific processors: Compressor , De-esser, Enhancer, Expander/Gate. These four processors can be used in any combina-tion or the 286A can be set as a dedicated single-function processor (refer to the fol-lowing pages).A compressor is a device that changes its gain in response to the signal at its input.Many compressors have a user-selectable level, called THRESHOLD, to help deter-mine when compression occurs. If the input signal is low in level (below the thresh-old of compression) the compressor gain remains fixed. If the input increases abovethe threshold of compression, the gain begins to decrease (i.e., the amount of gainreduction increases). For very large input signals, the gain can decrease considerably.On the 286A, compression occurs as an input level is “driven” into gain reduction bythe DRIVE control; as the DRIVE setting (adjusted clockwise from OFF) increasesinput gain, the amount of gain reduction also increases. The 286A does not have aThreshold control; the threshold is established by the setting of the DRIVE control.Use the Drive control to set the amount of gain reduction (i.e., how much the inputsignal is being compressed). Use the DENSITY control to set the compressor’s

De-Esser Enhancer release time (i.e., how fast the compression circuit returns the input to its original level). The 286A’s patented and versatile Compressor can smoothly and unobtrusively ride gain, and assertively increase punch and density. The 286A achieves its outstanding- ly transparent audio performance by finely-tuned control circuitry that eliminates the dynamic distortions present in most conventional compressors and limiters. The use of a quiet, low-distortion dbx VCA ensures negligible static distortion and noise. Compression is especially useful for smoothing out a vocal performance, raising a signal out of a mix, fattening kick or snare drums, or adding sustain to instruments (such as an acoustic guitar or bass). A De-Esser is a device that reduces the high frequency energy present in certain vocalizations, of which the most common is sibilance. Sibilance is the hissing or rushing sound produced by blowing air through a constricted (narrow) mouth opening or across the edge of the teeth, as in the “s” and “sh” in “sash.” Sibilants contain pre- dominantly high frequency components with a sharp rise above 1kHz and most of the energy in the 4kHz to 10kHz band, centered on 6kHz to 8kHz. Adjust the De-Esser’s FREQUENCY control to set the frequency above which the 286A responds to audio containing sibilants. The 286A detects sibilant material by comparing the high-frequency energy of an audio signal to the full bandwidth energy of that signal. When the high-frequency energy is excessive relative to the full band- width energy, the 286A quickly reduces the gain, or “de-esses.” The frequency con- trol sets the high-pass filter frequency of the high-frequency level detector. For nor- mal vocal de-essing, the frequency should be set between 4-8kHz. Further adjustment of the frequency control enables the 286A to be used for processing instrumental material, such as removing “clicks” from a close mic’d piano or acoustic guitar. Adjust the De-Esser’s THRESHOLD control to quickly reduce any sibilance (i.e., excessive vocal sounds like “sss”), high-frequency overload distortion (e.g., a cymbal crash that can overload tape, drive amps into distortion and fatigue listeners), or even guitar string slide noise. We recommend the 286A’s De-Esser for use almost exclusively on single voices or instruments for sibilance. The De-Esser should not be used on mixed program mater- ial. An Enhancer (sometimes called a Spectral Enhancer) adds clarity and detail to vocals or other line level signals by “intelligently’ boosting specific frequency ranges. Use the HF DETAIL control to add high frequency energy to the input signal. Use the LF DETAIL to add punch and definition at the lower end of the spectrum. The HF Detail circuitry in the 286A uses a dynamic shelving equalizer to provide results superior to even complex equalization. In many situations, the amount of high frequency content in the material you are working with will vary. Typical equaliza- tion schemes will produce results which are right some of the time, and completely wrong at other times. But not with the 286A. The equalizer’s dynamic operation and sliding corner frequency ensure that high frequency enhancement is applied only when needed and in the specific frequency range necessary to maintain proper spec- tral balance moment to moment. HF detail is perfect for adding definition to muddy vocals, guitar or horn tracks. It can also add “zing” and crispness to percussion tracks - acoustic or sampled.Mic Preamp/ Processor 286A

Expander/Gate Using the Four Processors in Different Combinations As you increase the amount of LF Detail, the circuitry boosts lower bass frequencies while simultaneously cutting problem frequencies in the upper bass/low midrange region which often makes program material muddy. Use LF Detail to create a “big,” chesty, male voice or to add fullness and power to lower frequency percussives (e.g., kick, toms, timpani). A Gate is essentially a device that controls the level of an input signal by “opening” and “closing.” A user-selected level, called THRESHOLD, helps determine when the gate opens and closes. If the input signal is above the threshold, the gate is “open,” allowing the signal to pass. If the input signal is below the threshold, the gate “clos- es” and the input signal is attenuated. With sufficient attenuation, it effectively cuts that signal off. On the 286A, the amount of attenuation is set with the EXPANSION RATIO control. The 286A’s gate provides more flexibility than traditional switch gates because it actually functions as a combination gate/expander. Where switch gates are generally only suitable for a limited number of uses (e.g., gating percussion), the gate on the 286A acts as a gentle downward expander at low EXPANSION RATIO settings (suit- able for vocals, guitar, etc.) and can effectively work as a switch gate when used at high EXPANSION RATIO settings. When an input signal exceeds the user-selected THRESHOLD, signals pass unaffect- ed. However, when part of a signal is below THRESHOLD, that part is downward expanded. (This differs from gating in that the attenuation effect of downward expansion is gentle.) Downward expansion works well with program material that has a less defined attack and release. Use downward expansion with voice - as opposed to percussive sounds which have a quick, defined attach and release. Adjust the Expander/Gate THRESHOLD and EXPANSION RATIO controls to pre- vent headphone leakage or to cut the background noise when gain is added at all the preceding stages of the 286A. Note: Too high of a THRESHOLD setting with expansion (i.e., lower EXPANSION RATIOs), may cause the286A to attenuate the desired portion of the signal, as well as the undesired portion. Too high of anEXPANSION RATIO setting my cause undesirable effects with highly modulated program material likevocals.Note: The following example is provided as a guide to highlight how the 286A’s front panel controls can beused simultaneously for multiple purposes. Suggested settings are specific to this example. Once youhave connected the 286A to your system (see page 7), adjust the 286A’s controls as required to supportyour setup and to achieve your desired results (refer to Suggested Settings/Usages, below). An Example: You are using a condenser microphone to record a vocalist whose “sss” sounds sting while the overall character of the vocal part is rather dull and the vocal- ist is constantly changing his/her distance from the microphone, and your studio is complete with hum from bad cabling, and noise from heavy construction work near- by. The 286A can be used to rectify each of these problems and also provide addi- tional processing to highlight the best qualities of the vocal performance. Press the PHANTOM POWER button in to support the phantom power mic (after reducing playback gain). Press the HIGHPASS button in to reduce the hum. Adjust the Compressor DRIVE and DENSITY controls to smooth out the vocal per- formance. To slow the compressor’s release time, set the DENSITY control to 0. Set the De-Esser frequency control to 4kHz (12:00 position). Adjust the De-Esser THRESHOLD control to reduce the vocalist’s sibilance. 9Mic Preamp/ Processor 286A

Suggested Settings/Usages Use the HF DETAIL, to taste, to add life to the vocal. Defeat the LF DETAIL by set- ting it to OFF. Set the Expander/Gate THRESHOLD and EXPANSION RATIO controls starting with a setting of around 11:00. Adjust these controls so that background noises are gated out when the vocal part is low or not present. Because minimal processing levels often produce the best results, the 286A’s process- ing should initially be applied conservatively (to taste); avoid overusing an effect, unless it is absolutely necessary. (For example, use De-Essing for sibilance or high frequency distortion only; otherwise, turn the control OFF. Or, for material already rich in high frequencies, set the HF DETAIL to Off, or use it minimally.) This will ensure that the 286A’s circuitry produces superior audio without any arti- facts.

• Expander/Gate Note: The Expander/Gate is OFF when the Expander/Gate THRESHOLD is set to the “off” position. Suggested Initial Gate settings: Gating Dry Percussive Sounds (i.e.: Snare Drum, Kick Drum) Gating Sounds that have Longer Decay (i.e.: Cymbal, Piano) Gating Hum or Buzz from Live Instruments or Recorded Tracks Downward Expansion to Reduce Noise Under Smooth Sounds (i.e.: Vocals, Woodwinds)

• Enhancer Note: The High and Low Frequency Enhancers are OFF when their respective DETAIL controls are set to the “off” position. Suggested Usage: Female Male Strings/ ClubVoice Voice Keyboard Guitar Bass Guitar Drums Horns Sound/

Detail Recommended; These sound sources can be effectively re-energized and enhanced with treatment. Use to taste. Program-Dependent; Use when program material needs treatment. Make sure you use only as much treatment as needed. -- Not Recommended. The 286A is generally not applicable to these applications.Mic Preamp/ Processor 286A

Noise Rushups, Hiss BuildupAlways verify that the problem is not in the source material being fed into the 286A,or in the other parts of the system. If you still have problems when using the 286A,consider the following remedies.Higher DRIVE settings on the compressor often add gain to the signal. If the signalalready has substantial hiss, the compression can actually increase the hiss. As acompressor releases and the gain of the input signal increases, background noise andhiss can increase. This is called noise rushup. Remedy this by using compressionconservatively. Also, to reduce noise rushups, especially during pauses, lower theCompressor DENSITY setting. For both cases, set the Expander/Gate to match thecompressor’s release time, thereby gating out the noise or hiss as much as possiblewithout truncating the signal.Increased hiss can also result from high frequency “detailing.” The HF DETAILenhancer estimates how much high frequency boost is appropriate for a given inputsignal. If the signal is dull but noisy (e.g., vocals recorded to a bad cassette), the HFDETAIL will make it brighter and can pull up hiss to objectionable levels. (The hisswill often be audibly modulated by the material because the HF DETAIL is adaptiveto the material.) Reduce the setting of the HF DETAIL control until the effect is nolonger objectionable.dbx Professional Products manufactures several processors that are more suitable forthis type of low-quality material because they have built-in dynamic single-endednoise reduction circuits. The dbx Project 1 296 Spectral Enhancer features hissreduction and Spectral Enhancement all in one unit. The dbx 563X and 929“Silencers” provide over 30dB of hiss reduction only.

• CompressorNote: The Compressor is OFF when the Compressor DRIVE is set to the “off” position.Suggested Initial Compressor settings:Smoothing Out A VocalPerformanceRaising a Signal Out of a MixFattening a Kick Drum or Snare DrumAdding Sustain to Guitar orSynthesizer String Sounds PROBLEMS,POSSIBLE CAUSES,SOLUTIONSMic Preamp/ Processor 286A

For multitrack studio applications, consider gating out the hiss during the initial recording, then adding HF DETAIL enhancement afterwards, during mixdown. With certain combinations of controls, especially when they are used at more extreme settings (towards fully clockwise), distortion or artifacts may occur. In this case, lessen one of more of the controls in use. For example, higher DRIVE settings on the compressor often add gain to low-level signal, especially when used in conjunc- tion with other controls. To reduce distortion, simply reduce the compression setting. If you still want more compression, return the compression to its previous setting, and reduce one or more of the other controls which commonly increase gain (e.g., Enhancer DETAIL controls, MIC GAIN, etc.). Setting the DENSITY control higher than the 12:00 position can sometimes cause audible distortion in the bass because the very fast release time begins to modulate each individual cycle of the bass waveform. If this occurs, turn down the DENSITY control. (Patented circuitry in the 286A greatly reduces this effect when compared to many other compressors operated at equally fast release times). Higher Expander/Gate settings can cut off sounds prematurely, specifically after a sudden transient or loud note has decayed. This could result in unintelligible vocals, incomplete chords, inferior cymbal splashes, lost reverb tails, etc. To retain the com- plete input signal, but still maintain required expansion and gating (e.g., to reduce settings until the complete signal is adequately restored. This means that you should set the Expander/Gate controls so that the red (-) THRESHOLD LED (located to the right of the EXPANSION RATIO control) does not light until the required signal is finished. With higher settings of the De-Esser THRESHOLD or Expander/Gate THRESHOLD controls, a vocal performance can be marred by resultant lisps (i.e., where s and z sounds are heard as th sounds). Lisps can usually be corrected by reducing the De- Esser THRESHOLD, or the Expander/Gate THRESHOLD, or both. If high frequency energy in the audio is producing shrillness or excessive brightness, try reducing the HF DETAIL or increasing the De-Esser THRESHOLD (if the audio is a single track), as appropriate. Although the HIGHPASS button works effectively to reduce hum, rumble, wind noise, etc., at the input, LF DETAIL can restore low frequency power to objection- able levels if used too liberally. This is especially true if the rear panel INSERT is used; this places a unit (e.g., an equalizer) directly between the Mic Preamp Section and Processing Section of the 286A - hum or other undesirable low frequencies “inserted” by the device cannot be corrected by the HIGHPASS button. In most cases, make sure the LF DETAIL is used conservatively. Increase MIC GAIN or Compressor DRIVE. Audible Distortion, Etc. Sound Cutting Off Lispy Vocals Shrillness or Excessive Brightness Low Rumble or Excessive Low Frequencies No Gain Reduction Metering Shown When Compression is In (i.e., Compression DRIVE control is active).Mic Preamp/ Processor 286A

The 286A is an all-solid-state product with components chosen for high performanceand excellent reliability. Each 286A is tested, burned in and calibrated at the factoryand should require no internal adjustment of any type throughout the life of the unit.We recommend that your 286A be returned to the factory only after referring to themanual and consulting with Customer Service.Our phone number, fax number and address are listed on the back cover of this man-ual. When you contact dbx Customer Service, be prepared to accurately describe theproblem. Know the serial number of your unit -- this is printed on a sticker attachedto the rear panel.Note: Please refer to the terms of your Limited Two-Year Standard Warranty, which extends to the first end-user. After expiration of the warranty, a reasonable charge will be made for parts, labor, and packing if youchoose to use the factory service facility. In all cases, you are responsible for transportation charges to thefactory. dbx will pay return shipping if the unit still under warranty.Shipping Instructions: Use the original packing material if it is available. Mark thepackage with the name of the shipper, and with these words in red: DELICATEINSTRUMENT, FRAGILE! Insure the package properly. Ship prepaid, not collect.Do not ship parcel post.We appreciate your feedback. After you have an opportunity to use your new 286A,please complete the Registration Card and return it.This warranty is valid only for the original purchaser and only in the United States. 1. The warranty registration card that accompanies this product must be mailed with-in 30 days after purchase date to validate this warranty. Proof-of-purchase is con-sidered to be the burden of the consumer.2. dbx warrants this product, when bought and used solely within the U.S., to be freefrom defects in materials and workmanship under normal use and service. 3. dbx liability under this warranty is limited to repairing or, at our discretion, replac-ing defective materials that show evidence of defect, provided the product isreturned to dbx WITH RETURN AUTHORIZATION from the factory, where allparts and labor will be covered up to a period of two years. A Return Authorizationnumber must be obtained from dbx by telephone. The company shall not be liablefor any consequential damage as a result of the product's use in any circuit orassembly.4. dbx reserves the right to make changes in design or make additions to or improve-ments upon this product without incurring any obligation to install the same addi-tions or improvements on products previously manufactured.5. The foregoing is in lieu of all other warranties, expressed or implied, and dbx nei-ther assumes nor authorizes any person to assume on its behalf any obligation orliability in connection with the sale of this product. In no event shall dbx or itsdealers be liable for special or consequential damages or from any delay in the per-formance of this warranty due to causes beyond their control.

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