Aphex 320D Compellor user_manual 电路图.pdf

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1、Owners Manual Dual Mono/Stereo Automatic Level Controller with Analog Peak-vs-RMS: How To Deal With The Confusion - Page 38 1. Contents 320D Compellor Page 4Page 5 320D Compellor Page 6Page 7 You can use this quick setup to get a signal through your Compellor right away. Then. youll want to go on an

2、d read through the manual to discover the wealth of information that is available to you. Quick Start 1. Make sure there is signal going through the Compellor with Process both “In” and “Out”. If not, check the input and output wiring. They may be reversed. Be sure to check for the cor- rect input s

3、election (analog or digital) on the rear panel. Leave Compellor in bypass (Process “OUT”) until finished with set up. 2. For Analog In: Set rear panel Input Select to Analog. Send a zero VU tone into the Compellor (at +4dBu or -10dBV depending on your operating level settings). Check to see the rear

4、 panel REF LEVEL switches are set for your operating level. If you do not have a tone generator, use program material that averages around zero VU in your system. For Digital In: Set rear panel Input Select to AES3. Send a digital tone at -20dBFS. 3. Switch Compellor “Meter Select” to Input. The las

5、t red LED should indicate approxi- mately 0 on the meter. If not, adjust the rear panel REF LEVEL switch to the position which gives you the closest reading to 0. NOTE: This switch only affects the analog I/O. The digital input is internally calibrated and is guaranteed to match -20dBFS to 0VU on th

6、e Compellors meter. 4. Set the Process Balance to 12 oclock. 5. Switch the Meter Select to G.R. (gain reduction). Adjust the Drive control to achieve 12dB of gain reduction with 0VU input. The last lighted LED shows the total amount of gain reduc- tion occurring. 6. Set Leveling Speed to Slow if you

7、 are controlling full program, Fast if you are controlling live voice. 7. Set Limiter “On”. 8. Set the Silence Gate to 12 oclock. 9. Stereo Enhance: If using the Compellor for mono or dual mono operation, switch the Stereo Enhance to “Off”. If using the Compellor for stereo program, switch the Stere

8、o Enhance to “In”. 10. Link: If using the Compellor for mono or dual mono operation, press the “Unlink” button. If using the Compellor for a normal stereo program, switch the Link to “Leveling”. If using the Compellor for any matrixed stereo program (e.g.- surround encoded), switch the Link to “Leve

9、ling 48kHz standard Word Clock: Not Supported 5.10 OTHER SPECIFICATIONS AC input: IEC standard receptacle with voltage selector, fuse, the AES3 in is directly tied to the AES3 out. If power fails, the bypass condition is automatically set, providing a fail-safe feature for mission critical audio cha

10、ins. A condition that can cause trouble if not understood is when you are operating the 320D in a system that feeds analog audio to the Compellor but takes the AES3 digital output. Obviously, 6. Using Digital Audio ANALOG CH2DIGITAL AES3INPUT AUDIO SOURCE SELECT IN32-96kHzOUTIN OP LEVEL -10 +4 ANALO

11、G DIGITAL 320D Compellor Page 16Page 17 when in Bypass, the Compellor cannot feed the analog input to the digital output. The digital output will simply go dead with no carrier. There is no practical way to avoid this. NOTE: Because the digital I/O is inherently a stereo interface (two channels on o

12、ne AES/EBU connection), the Model 320D must have both bypass switches set to Bypass in order to get the digital I/O to go into bypass. The analog I/O will bypass on a per channel basis, however. 6.6 Sample Rates The 320D accepts any sample rate from 32kHz to 96kHz. If there is no digital input prese

13、nt, the 320D will automatically sync to its own internal clock frequency, giving the possibility of having an analog input and a non house-synchronized digital output. With no AES3 input present, the 320D defaults to an internal crystal clock to determine the self-generated AES3 sample rate. The rat

14、e is fixed and not selectable. However, the crystal can be changed by the user to obtain the desired sample rate. The 320D comes with the 48kHz crystal already installed and a kit of extra crystals for the sample rates of 32, 44.1, and 96kHz is packed inside each 320D. If you need to change the 320D

15、s default sample rate, use the following procedure to change the crystal. 6.7 Changing The Crystal a. Make sure the power cord is unplugged and the unit has been off for several minutes. b. Remove the top cover from the chassis and locate the crystal kit packed packed inside. c. Locate the digital a

16、udio interface board as shown in figure 6.1. d. Locate the crystal Y2. Its wire pins are inserted into socket receptacles on the board and the case is held in place with a dab of silicone glue. e. Carefully pull the crystal out of the socket. If necessary, cut or peel off the glue to release the cry

17、stal. Clean any residual glue from the pc board. f. Insert the new crystal until it is fully seated in the pin receptacles. Add a dab of silicone glue to hold it in place. Refer to Table 6-1 to select crystal frequencies. NOTE: DO NOT USE SUPER GLUE. IT MAY RUN DOWN THE PINS AND RENDER THE OSCILLATO

18、R INOPERABLE. Fig 6.1 Location of Y2 Crystal Sample Rate kHz 32.0 44.1 48.0 96.0 Frequency mHz Table 6-1 Crystal Frequencies 8.1920 11.2896 12.2880 24.5760 320D Compellor Page 18Page 19 7.1 Introduction The “Quick Start” guide in the front of this manual is the best way to begin using your Compellor

19、. You will get a good feel for what is going on, and you will have a signal going through the processor, ready for fine tuning. We strongly recommend reading section 8 describing the Compellors features and controls in order to understand what all the settings mean. For the present purposes, we will

20、 discuss specific applications of a Compellor and give you suggestions on how to tune it for best results. 7.2 Recording Regardless of how consistent a musician or a vocalist may be, when there is a take the levels can vary dramatically from the rehearsals. Trying to ride faders in real time is impr

21、actical, if not impossible. You want to have real time control over the levels, but not change the musical character of what you are recording. The Compellor is the perfect solution. Set up the Compellor for no more than 4 to 6dB of gain reduction with nominal 0 VU in, use fast leveling speed with P

22、rocess Balance at 12 to 1 oclock. This setting will give you 4 to 6dB of increase in the lowest level signals and keep overly enthusiastic performers from overload- ing the recorder. When using the Compellor as a dual mono unit make sure that the Stereo Enhance is off and the Unlinked is in. Using t

23、he Compellor while recording will give you more consistent levels to work with when you mix, thus making the mix process faster and easier. It will also allow you to maintain better signal to noise performance in the recording medium. 7.3 Mixing Layering elements within a mix so that each sits in it

24、s own pocket, not interfering with other elements is a critical part of assembling a high quality mix. Typical multitrack mix downs become very complex. Gain adjustments on the different elements can be manually made through the mix, programmed through automation, or the Compellor can be used. By us

25、ing the Compellor on an individual track or subgroup, that element can be fit into the mix more easily and require less attention from the mix engineer. A background vocal subgroup, for example, may disappear into the noise or become lead vocals. By using the Compellor, the background vocals stay in

26、 the background, but at the right level. Use one channel of the Compellor as a pre-fader insert, or on the output of a buss and return the buss into a fader. This will give you the ability to automatically control the levels of the element and also adjust the level of the return if necessary. Note:

27、If you insert the Compellor post-fader, the Compellor will unwind any fader moves. Using the Drive control, adjust the amount of total gain reduction for the amount you want to bring up the lowest level signal (usually no more than 6 to 8dB). Process Balance should be set more towards Leveling (CCW)

28、 for a more dynamic sound and more towards Compress for tighter instantaneous dynamics. 7.4 Mastering A recording studio is not the typical listening environment. Most listening is done in a higher noise environment with less than optimal acoustics (e.g.- a car). Monitoring in a studio is usually do

29、ne at higher levels than in a typical playback situation. Furthermore, if the master 7. Operation 320D Compellor Page 18Page 19 has too wide a dynamic range, it can cause broadcast processors (if the processing does not include the Compellor) to work too hard and generate audible artifacts. These ar

30、e all reasons to master a final mix which has a controlled dynamic range. The goal, of course, is to maintain the sound quality of the studio while you are trying to tighten the mix. Adjust the Compellor for 2 to 4dB of gain reduction with the Process Balance at 11 oclock. Stereo Enhance should be i

31、n and Leveling Link in. If the mix was encoded for surround or has some other matrix processing, use the Compression and Leveling Link. Note: If there is one dominant element in your mix, the Compellor will work on that element causing the lower level elements to be ducked. It is therefore important

32、 to control the elements in the recording and the mix down before the mastering process. 7.5 Video Post-Production Speed is of the utmost importance in video production. There is no time to do endless takes and overdubs, ride faders or program automation level changes. But the demand to have a quali

33、ty end product still remains. The Compellor will automatically control and blend levels from multiple sources and takes. 7.6 Sound Reinforcement: Each music or speech source can have its own variation of level. Multiple sources can have extreme variation in levels. Some examples- a fire and brimston

34、e preacher followed by a little girl on the same P.A. system, a foreground music system playing from a juke box and the selections all have different levels, one speaker in a confer- ence room trying to shout down a more soft-spoken individual. The Compellor controls the level variations within a so

35、urce and the segue between sources is much smoother in terms of level. Adjust the Compellor so that the amount of gain reduction with 0 VU in is the desired amount of gain you want to add to the lowest level signal. Caution: Since the Compellor is so transparent, even at great amounts of gain reduct

36、ion, it is hard to tell when there is too much gain reduction. If there is an open microphone, there may be feedback if the Compellor brings up too much gain. Make sure that there is no feedback when the Compellor is fully released (i.e.-no gain reduction). 7.7 Live Concerts As in a recording enviro

37、nment, artists will often play at much different levels at different times. Controlling dynamics becomes even more important because there is no way to fix it in the mix. Use the Compellor on individual elements or subgroups and you will not have to work the fad- ers as often or as hard. The Compell

38、or can be used as a final gain rider so that the average level of the concert stays within defined dynamic range. Be careful not to use too much gain reduction on vocals and instruments which are miked so that you avoid feedback when the Compellor is fully released. 7.8 Broadcast Radio Pre-processin

39、g Levels coming off the studio board are unpredictable, even with an operator watching levels. Level differences from cart to CD to voice to satellite and back can be dramatic. There are Houses of Worship Restaurants Discos Paging Systems Conference Rooms 320D Compellor Page 20Page 21 numerous other

40、 devices which effectively control the level differences, but none have the transparency of the Compellor. These other devices, particularly multiband compressors and limiters, have a sweet spot which renders the best results. Adjust the Compellor so that its output is driving the downstream process

41、ors at their sweet spot. 7.9 Broadcast STL/ Phone Line Driver The aural STLs and phone lines have limited dynamic range. It is advisable to do processing in front of those links so that they are not overloaded or driven so lightly that there is too much noise. Set the Compellor for 12dB of gain redu

42、ction, Process Balance at 11 oclock, Leveling Speed slow, Limiting in, Stereo Enhance in and Leveling Link in. 7.10 Television Broadcasting and Cable Systems The single biggest complaint generator from viewers is the apparent level difference between commercials and program. The differences may be e

43、ven more exaggerated when there are local inserts into national feeds. Commercials are processed to have low peak to average ratios. So even if the peaks of the commercials are the same as the program peaks (as would be measured on a modulation monitor) the average levels are higher, causing the app

44、arent loudness difference. The Compellor recognizes the differences in density and adjusts it release times based on the peak to average ratio of the input. If an input is already heavily processed (e.g.- a com- mercial), the Compellor slows its release time. When the Compellor sees a very high peak

45、 to average ratio (e.g.- a live news broadcast) it speeds its release time. Segues between program and commercials are much smoother. Another complaint made to cable systems is the difference of levels channel to channel. If each channel of a cable system has a Compellor and all the Compellors in a

46、cable system are set similarly, channel to channel differences will be eliminated. 7.11 Video and Audio Tape Duplication The dynamic range of most tape formats is usually much less than the original source mate- rial. In addition, the usable dynamic range of the playback medium of duplicated tape is

47、 usu- ally less than that of the original (e.g.- video tape copy of a theatrical release). The Compellor will automatically control the dynamics of the original without losing the impact and artistic intent of the original. The Compellor is also useful when assembling a single tape from multiple sou

48、rces. The level differences between the sources are automatically smoothed out, obviating the need for stu- dio time to level adjust each source before mastering. 7.12 Voice Processing The human voice is the most difficult signal to process. We may not know what that drum sounded like originally, bu

49、t we all know what a human voice sounds like. Processing artifacts are therefor much more noticeable on human voices. Consonant recognition is a critical part of intelligibility. If the processing is not done correctly, the consonants will be crushed causing the loss of intelligibility. The Compellor effectively controls the levels without loss of intelligibility, indeed because the levels are more controlled, the intelligibility will be enhanced. It is recommended that Leveling Speed be set for fast when processing voices. 7. Operation 320D Compellor Page 20Page