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6.5 Release

Release determines how quickly the compressor returns to normal gain
following a transient over the threshold. The setting of the release time can be
varied from 5ms to 2s, and is very much dependant on program type. The
times printed around the control refer to the approximate time taken for the
signal to be recovered to 90% of from the initial level. The setting of a wrong
speed will result in one of the following conditions:

This control determines how quickly the DPR-422 compressor responds to
signals once the threshold is exceeded and provides a range of times from 50us
to 100ms. For transient signals (very sudden 'spikes' in the signal that last a
short time), a fast attack time is desirable. For other types of program material a
slower time will be more useful. It is always better to start with a slower time,
and progressively speed up the response as necessary, since too fast a time
may cause distortion of the sound, especially with signals that contain a lot of
low frequencies. The times printed around the control refer to the approximate
time taken for the signal to be reduced by two thirds of the ultimate reduction.

6.4 Attack

Summary of Contents for DPR 422

Page 1: ...1 DPR 422 User Manual...

Page 2: ...TY CERTIFICATION VOID For continued compliance with international EMC legislation ensure that all input and output cables are wired with the cable screen connected to Pin 1 of the XLR connectors and o...

Page 3: ...Chain Inputs 11 5 4 Side Chain Outputs 12 6 0 Control Operations 13 6 1 Operating Level 13 6 2 Threshold 13 6 3 Ratio 14 6 4 Attack 15 6 5 Release 15 6 6 AUTO 16 6 7 Stereo Link 16 6 8 Gain 17 6 9 Cha...

Page 4: ...25 8 5 Broadband De essing 25 8 6 HF De essing 25 9 0 Operation and applications 26 9 1 Compression 26 9 2 De essing 26 9 3 HF De essing 27 9 4 HF De essing with full Dynamic control 27 9 5 Peak Limi...

Page 5: ...t mounting flange The necessary support can generally be bought ready built as a rack tray or the DPR 422 can be mounted between other units Damage caused by insufficient support is not covered in the...

Page 6: ...selector switch on the rear of the unit It is vital that the position of this switch is checked BEFORE initial power up to ensure that it matches the local mains supply Acceptable input AC supply volt...

Page 7: ...odification being applied to the input signal Two modes of de essing are available on the DPR 422 A dedicated broadband de esser allows wide band sibilance control simultaneously and independently fro...

Page 8: ...8 The DPR 422 Fig 4 2 Rear Panel Fig 4 1 Front Panel...

Page 9: ...9 All numbers in bubbles refer to Section numbers...

Page 10: ...ted to pin 1 to ensure that EMC regulations are being met and the cable shield ground should also be connected to the equipment which is providing the input signal When feeding the DPR 422 from unbala...

Page 11: ...sure continued compliance with EMC regulations The cable shield ground should be connected to the equipment which is providing the input signal When feeding the DPR 422 from unbalanced sources connect...

Page 12: ...available into any load of 2k Ohms or greater The signal HOT or in phase signal is to the jack plug tip The COLD or out of phase signal is to the ring with the shield being connected directly to the...

Page 13: ...order to set the compressor to the required amount of gain reduction For example if the average input is 12dBu and the THRESHOLD control is set to 10dBu then the top 22dB 12 10 22dB of the signal can...

Page 14: ...high levels of compression the transfer becomes harder This progressive knee gives inaudible compression for low levels of ratio and gain reduction whilst allowing harder compression for effective li...

Page 15: ...the DPR 422 compressor responds to signals once the threshold is exceeded and provides a range of times from 50us to 100ms For transient signals very sudden spikes in the signal that last a short tim...

Page 16: ...attack time setting and a two part program related release time setting The two part program dependant release provides a fast release to restore below threshold gain as soon as the transient has pas...

Page 17: ...ill often be less than the input The GAIN control is provided to restore the output signal to the desired operating point and provides a calibrated range of 20dB relative to the input signal The facil...

Page 18: ...cy in the sibilance sound To aid the setting of the frequency control the SIDE CHAIN LISTEN switch can be depressed and the onset of the lowest sibilant frequency at the output of the selection filter...

Page 19: ...be used by connecting the two channels in series with an external cable 6 13 Side Chain Listen If the DPR 422 is in compress mode de ess HF switch out depressing this switch will switch the output of...

Page 20: ...levels are similar the GAIN control will only affect the output signal level Once satisfied that the levels are matched operation of the CHANNEL IN switch will ensure an unnoticeable drop in Metering...

Page 21: ...t the output to have only increased by 6dB providing the attack and release controls are set accordingly Assuming the gain control is at 0dB the difference between the input and output levels of 6dB t...

Page 22: ...ortion at the upper end The usable dynamic range sits in between these two limits and it is common practice to operate a piece of equipment at a level that is somewhat below the upper distortion point...

Page 23: ...gnal gradually so that they are acceptable to following equipment For limiters the threshold point will be set above the operating level in order to provide a maximum level for signals to following eq...

Page 24: ...ld level Fig 8 3a High threshold level Comparing the input and output waveforms for the compressed mode the loudest portions of the signal have been effectively decreased in level and if the gain cont...

Page 25: ...ol it will start to gain reduce the program level As this reduction occurs over the whole frequency range of the program it is called broadband de essing Remember though that no reduction occurs unles...

Page 26: ...ignificant low frequencies Rotate the THRESHOLD control anticlockwise until the BELOW THRESHOLD meter is fully illuminated and an appropriate amount of gain is indicated on the GAIN REDUCTION meter Th...

Page 27: ...program that exceed the norm will now be hard limited as the RATIO control is set to infinite The GAIN control should be set so that the limited output of the DPR 422 matches that expected by followi...

Page 28: ...you have an input signal Check the Input and Output connections Are the power amplifiers switched on Problem Fuse failure Solution The mains supply fuse is unlikely to blow without an electronic fault...

Page 29: ...ed in the European Union you may as an alternative return the unit to any other BSS distributor in the European Union You should include a statement listing the faults found The unit s serial number m...

Page 30: ...range 30dB to 20dB continuously variable Compressor ratio 1 1 to infinity 1 continuously variable Maximum VCA range 30dB Distortion Typically 0 05 THD 80kHz measurement BW 2kHz 0dBu out with 6dB gain...

Page 31: ...input to output gain as the input signal increases above a predetermined threshold level dB A unit for expressing the ratio between two signal levels for comparison purposes On its own it has no abso...

Page 32: ...om The amount in dBs above the normal operating level that can be used before serious distortion commences Impedance The AC equivalent of resistance and measured in ohms It indicates the amount of dri...

Page 33: ...small period of time relative to the rest of the signal The level of these transients can often reach 10 times 20dB or so above the normal operating level of the audio equipment and may cause distort...

Page 34: ...S Side chain insert application 27 Side Chain Listen 19 Specifications 30 Stereo Link 16 A Attack 15 Audio connections Inputs 10 Outputs 10 Side Chain Inputs 11 Side Chain Outputs 12 AUTO 16 B Breathi...

Page 35: ...35 T Threshold 13 Troubleshooting 28 U Unpacking 7 V Voltage Controlled Attenuator 13 Voltage selection 6 W Warranty 29...

Page 36: ...36 User Notes...

Page 37: ...37...

Page 38: ...38 User Notes...

Page 39: ...39...

Page 40: ...40 User Notes...

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