MODEL 160A COMPRESSOR LIMITER
IMPORTANT SAFETY INFORMATION WARNING FOR YOUR PROTECTION READ THE FOLLOWING: CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN A T T E N T I O N : RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR W A R N I N G : TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE The symbols shown above are internationally accepted symbols that warn of potential hazards with electrical products.
IMPORTANT SAFETY INFORMATION DECLARATION OF CONFORMITY ELECTROMAGNETIC COMPATIBILITY This unit conforms to the Product Specifications noted on the Declaration of Conformity. Operation is subject to the following two conditions: • • t his device may not cause harmful interference, and this device must accept any interference received, including interference that may cause undesired operation. Manufacturer’s Name: dbx Professional Products Manufacturer’s Address: 8760 S.
dbx 160A COMPRESSOR / LIMITER Manual Contents Quick Set-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
dbx 160A COMPRESSOR / LIMITER QUICK SETUP To get your unit up and running as quickly as possible, do the following steps. For more detailed information, refer to the specified pages. • Unpack and Inspect the 160A Package. • Set Levels and Controls as Needed. • Connect the 160A to Your System.
dbx 160A COMPRESSOR / LIMITER APPLICATIONS The dbx 160A is capable of handling a wide range of applications. In the studio, the 160A can be used on everything from vocals to percussion. In live sound reinforcement, the 160A can allow the engineer to get that “fat studio sound” out of the drum kit or provide protection limiting for the speakers. It is also an excellent line driver, perfect for sending signals down long cables to power amp stacks or from remote broadcast trucks.
dbx 160A COMPRESSOR / LIMITER 1:1 Unity 1:1 RED Above Threshold +20 +15 2:1 +10 OUTPUT LEVEL (dB) 4:1 +5 20:1 0 :1 Rotation Point Threshold -15 -10 -5 0 4:1 +5 :1 0 −5 Above Threshold OverEasy Range EN −15 +5 +10 +15 +20 RED EORW MLBL YAE −10 GREEN Below Threshold -15 2:1 +10 RE -5 -10 +15 G OUTPUT LEVEL (dB) +20 Below Threshold −15 −10 −5 INPUT LEVEL (dB) +5 +10 +15 +20 0 INPUT LEVEL (dB) Figure 1: Hard Knee Compression Curve Figure 2: OverEasy® Compression Curv
dbx 160A COMPRESSOR / LIMITER +24dBu. This jack accepts 1/4” phone plugs. In normal operation the TRS phone jack is internally wired with the TIP HOT (+), and the RING and SLEEVE connected to ground. In Bypass mode, however, the RING is connected to the COLD (-) leads of the input jacks, to allow for balanced connections. GROUND (GND) Lift Switch: This switch allows for troubleshooting hum (line interference) caused by ground loops.
dbx 160A COMPRESSOR / LIMITER ∞ − − OUTPUT LEVEL (dB) +20 1:1 − +15 2:1 +10 4:1 +5 ∞:1 0 -5 Threshold -10 −1:1 -15 -15 -10 -5 0 +5 +10 +15 +20 INPUT LEVEL (dB) Figure 3: Ratio Control and Infinity+ (Negative) Ratios 160A by 1dB. See Figure 3 above. The control curve of the RATIO potentiometer has been designed to provide total operator control, with scale expansion at the subtle lower ratios for easy, repeatable settings.
dbx 160A COMPRESSOR / LIMITER Negative ratios can also be used to prevent musicians from continually increasing the volume of their instrument (e.g., in live applications where there is no sound engineer to control the house levels). With their signal compressed by a negative COMPRESSION RATIO, each volume increase initiated at the instrument or amp would actually decrease the volume level at the final mix.
dbx 160A COMPRESSOR / LIMITER As a general rule, compressors should be as close to the amplifiers as possible in the signal chain. If the 160A is placed before the EQ (equalizer), for example, a potentially damaging boost in the EQ won't be seen by the 160A and the speakers may be damaged. (see Multi-way speaker systems, page 9.) For maximum sound pressure levels, large sound reinforcement systems frequently use a separate compressor on each output of the electronic crossover(s).
dbx 160A COMPRESSOR / LIMITER The converse of the above EQ technique may be used: dipping the equalizer bands causes any sound with dominant energy in the affected register to pull the level up because the 160A will detect a need for less compression. De-Essing To apply de-essing to vocals (i.e.
dbx 160A COMPRESSOR / LIMITER -10 -20 BYPASS 160A SLAVE 4:1 3:1 0 -30 BELOW +10 ABOVE OVEREASY 2:1 0 6:1 10:1 :1 -5:1 -2:1 -10 -1:1 -20dB INPUT LEVEL +10 OUTPUT CONNECTING THE 160A TO YOUR SYSTEM -40dBu +20dBu 1:1 THRESHOLD +20dB OUTPUT GAIN COMPRESSION RATIO -40 30 20 15 10 8 6 5 4 3 2 1 0 1 2 4 6 10 20+ GAIN REDUCTION C O M P R E S S O R / L I M I T E R DISPLAY Basic Connection 85-3999-A 160AD front buyoff (5-20-98) 15 WATTS MANUFACTURED UNDER ONE OR M
dbx 160A COMPRESSOR / LIMITER “MASTER” “SLAVE” 160A 160A INPUT OUTPUT INPUT OUTPUT STEREO STRAPPING STEREO STRAPPING TO RIGHT INPUT TO LEFT INPUT FROM RIGHT OUTPUT FROM LEFT OUTPUT TRS “STEREO” CABLE (Shield plus two conductors) Figure 6: Multi-Channel Connections Using External Level Detector Inputs To control the compressor by signals other than the audio input (via an auxiliary device), connect the auxiliary device's output to the 160A's DETECTOR INPUT jack, and feed the auxiliary device's i
dbx 160A COMPRESSOR / LIMITER Note: DO NOT CONNECT the output of a power amp or the speaker out of an instrument to the input of the 160A. Severe damage system components may result. to Patch Bay In the studio, the 160A may be connected to a patch bay to allow it to be used anywhere in the studio system. If your studio is not fully balanced, you must ground the unused XLR pin (either pin 2 or 3) or use the 1/4” phone jack OUTPUT, which is single-ended.
dbx 160A COMPRESSOR / LIMITER Grounding For maximum hum rejection with a balanced source, avoid common grounding at the 160A's input and output. Most balanced (3-conductor) cables have the shield connected at both ends. This can result in ground loops which cause hum. If hum is a problem, try changing the position of the rear panel GROUND LIFT switch. This switch disconnects the input XLR pin 1 (the shield) from the 160A's chassis ground.
dbx 160A COMPRESSOR / LIMITER SPECIFICATIONS Input (1/4” TRS Phone and XLR) Impedance Maximum Level CMRR Floating Balanced; XLR: Pin 2 Hot, Phone: Tip Hot 100kΩ balanced, 50kΩ unbalanced +24dBu, Balanced or Unbalanced >45dB (any frequency) Detector Input (1/4” TRS Phone) Impedance Maximum Level Floating Balanced 400kΩ balanced, 200kΩ unbalanced +28dBu, Balanced or Unbalanced Output (XLR) Impedance Maximum Level (Balanced) Maximum Level (Unbalanced) Noise Frequency Re
dbx 160A COMPRESSOR / LIMITER NOTES 15
8760 South Sandy Pkwy. Sandy, Utah 84070 Phone: (801) 568-7660 Fax: (801) 568-7662 Questions or comments? E•mail us at: customer@dbxpro.com or visit our World Wide Web home page at: www.dbxpro.
