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This chapter also discusses the difference between “threaded” and “unthreaded” tapes. Chapter 2: Your First Session with the ADAT-XT20. This section provides a brief tour of the XT20, shows you how to format a tape, record and playback, set locate points, auto punch-in and out, bounce tracks, and points out other various features.
Analog Audio – Unbalanced Outputs Analog Audio – Balanced Inputs and Outputs Analog Input Select Mode Sync In/Out Digital Audio In/Out 32 About 16-bit and 20-bit signal transfers 32 Footswitches The XT20 Remote ASIC PERATIONS ADAT XT20 Reference Manual ADAT-XT20 Introduction/Contents...
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Introduction/Contents Tape Formatting Formatting Considerations Complete Format Recording While Formatting Format Extend 37 Write Protect Override 39 Reading The Display 40 Display Icons 41 TIME Counter & ABS/REL Button Locate 0 Basic Editing EDIT Value Button Buttons Entering Numeric Values Editing Individual Digits Input Select Analog Input...
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Tape Length Footswitch Controls Footswitch Controlled Punching Footswitch Controlled Autolocating Using the XT20 LRC Remote ADAT-XT20 O ULTIPLE Overview Synchronizing Machines Master/Slave Interaction Achieving Lock76 Independent Slave Mode Formatting Multiple Tapes Master Format Enabled, Complete Format Master Format Enabled, Format Extend 76...
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Introduction/Contents About Error Rate Readings ADAT Head Life ADAT Head Maintenance Drum Time Display Tape Maintenance: Safe Tape 102 Maintenance/Service Cleaning Maintenance Obtaining Repair Service RROR ODES Automatic Brake Calibration Procedure Steps To Take Before Calling For Help 107 PECIFICATIONS LOSSARY INDEX ADAT XT20 Reference Manual...
• Alesis warranty card It is important to register your purchase; if you have not already filled out your warranty card and mailed it back to Alesis, please take the time to do so now. AC P OWER With the XT20 off, plug the female end of the power cord into the XT20’s [POWER INPUT] socket and the male (plug) end into a source of AC power.
When AC currents are suspect of being highly unstable in VAC and Hz, a professional power conditioner should be used. Alesis cannot be responsible for problems caused by using the XT20 or any associated equipment with improper AC wiring. VOIDING In today’s studio, where it seems every piece of gear has a computer in...
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Setting Up: Chapter 1 should remain connected so that the shielding properties are retained, even if there is no direct path for ground.) Please note that not all hums and buzzes are caused by ground loops; your cables must be of very high quality, particularly with -10 dBV se- tups.
• Although Alesis does not endorse any specific product, chemicals such as Tweek and Cramolin, when applied to electrical connectors, are claimed to improve the electrical contact between connectors.
ASIC UDIO When connecting audio cables and/or turning power on and off, make sure that all devices in your system are turned off and the volume controls are turned down. The XT20 provides eight -10dBV unbalanced analog outputs via phono connectors.
Alesis recommends you use only premium quality, name brand S-VHS cassettes. We cannot overemphasize the importance of this. We recommend using Quantegy 489 DM Digital Mastering Audio Tape , or Alesis ADAT Mastering Audio Cassettes . Other acceptable brands include Maxell XR-S Black , JVC XZ , Sony DASV , BASF Digital Master 938 , Apogee AA-40 , HHB ADAT45 , and TDK SP Super Pro .
XT20 if any equipment will be mounted directly below it. OUNTING ON A To mount the XT20 on a shelf or other flat surface, Alesis recommends using the attached screw-on feet to avoid scratching the shelf’s surface with the deck’s bottom.
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Chapter 1: Setting Up strong magnetic fields such as power amplifiers, monitors and video display devices, speakers, etc. ADAT XT20 Reference Manual...
HAPTER XT20 OWER Connect the power cord which accompanies the XT20 between the three-prong power socket on the back panel and an AC outlet receptacle. Please note that there are grounding considerations to be aware of. See pages 7–9 for more information.
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Chapter 2: Your First Session With The ADAT XT20 -- -- -- -- Insert the tape with the hinged door end first, label side up, until you encounter a slight bit of resistance. Push gently on the center of the tape cassette until the XT20 draws the tape inward;...
ORMATTING Formatting prepares a tape for 8 channels of audio, and adds a master timecode reference, word length, and sample rate information to the data on tape. Similar to formatting a floppy disk to use on a computer or sampler, formatting an XT20 tape time-stamps the tape to single-sample accuracy so that audio is referenced to an accurate time base.
Chapter 2: Your First Session With The ADAT XT20 ECORDING You can record onto tape while formatting. Simply press any of the RECORD ENABLE buttons [1]–[8] for any track(s) you wish to record on before pressing the [FORMAT] button. Prepare your source material to start playback at 0:00:00.00 on the XT20 or later (do not begin recording before 0:00:00.00).
AKING Recording on the XT20 is very similar to most multitrack tape machines. The process involves formatting a tape (see previous tutorial), putting one or more tracks into record-ready, adjusting record levels on your mixer, setting the input monitor mode, locating to the start tape address and engaging record. In this tutorial, we will be recording from the analog audio inputs at the start of the audio portion of the tape (0:00:00.00).
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Chapter 2: Your First Session With The ADAT XT20 Before you start recording for the first time, be sure the TIME counter is set to ABS Time to avoid confusion. For more information, see page 41. ADAT XT20 Reference Manual...
RANSPORT During recording and playback, the following transport buttons are used frequently. Get familiar with them by using them while watching the TIME counter. REWIND High speed reverse. Press with [PLAY] to initiate review mode. FAST FWD High speed forward. Press with [PLAY] to initiate cue mode. S T O P Stops transport and disables recording.
Chapter 2: Your First Session With The ADAT XT20 Note: When recording for the first time, be sure the Auto Input function is off. When recording over previous material (also known as punching), turn the Auto Input function on. Use the [AUTO INPUT] button to turn Auto Input on and off.
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Your First Session With The ADAT XT20: Chapter 2 Both the [PLAY] and [FAST FWD] LEDs will turn off, and the [STOP] LED will turn on. ADAT XT20 Reference Manual...
Chapter 2: Your First Session With The ADAT XT20 OCATING Up to 10 tape positions can be stored for easy recall. These are called Locate Points, and can be stored either “on the fly” while the transport is engaged, or when the transport is stopped.
To set the Relative 0:00:00.00 position (Locate 0): Press [PLAY], [FAST FWD] or [REWIND] as required to move the tape to the position you wish to regard as “0:00:00.00” (Relative Time). Remember, ABS Time is the timecode being read from tape. Setting the Locate 0 position is always done in Relative Time.
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Chapter 2: Your First Session With The ADAT XT20 If the current Locate 1 position is set beyond the current Locate 4 position and Auto Return is turned on, the AUTO-RTN icon in the display will flash to indicate that Locate 1 or 4 will have to be set properly before this function will operate.
UTOMATED So far, all of your recording has been done manually — you pressed the transport buttons when you wanted to start and stop recording. Auto recording stops and starts recording automatically at predetermined times. This is useful when you want to precisely punch in to a specific place on one or more tracks. In this section, we will be storing the punch points (called Punch In and Punch Out) “on the fly”...
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Chapter 2: Your First Session With The ADAT XT20 that enabled for recording will switch from tape to input when the punch-in occurs, and back to tape when the punch-out occurs (this requires that the AUTO INPUT function be turned on). The [RECORD] LED will continue flashing throughout the punch in and out.
ITCH ONTROL The Pitch function controls the speed of the tape, and thus the pitch of the audio recorded on tape. The XT20’s Pitch control has a range of -300 to +100 cents when using a sample rate of 48kHz, and a range of -200 to +200 cents when using 44.1kHz.
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Chapter 2: Your First Session With The ADAT XT20 If necessary, repeat steps through to edit the delay value of any track. ADAT XT20 Reference Manual...
RACK It is possible to copy the audio material from one track to another on the same tape within the XT20 without leaving the digital domain and without the need for any audio cables. In fact, you can copy up to 4 tracks at a time using the Track Copy feature.
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Chapter 2: Your First Session With The ADAT XT20 ADAT XT20 Reference Manual...
HAPTER ONNECTIONS NALOG NPUT JACK CHARACTERISTICS The XT20 includes eight unbalanced phono jack inputs. These are compatible with low-impedance, unbalanced, -10 dBV outputs typical of equipment such as mixers, synthesizers, samplers, direct boxes, etc. The unbalanced input jack wiring convention is as follows: Signal Ground YPICAL INPUT JACK HOOKUPS...
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Chapter 3: Connections your mixer’s channel tape returns or line inputs. The outputs wiring scheme is similar to that of the unbalanced inputs (see previous section). ADAT XT20 Reference Manual...
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To run long distances and avoid hum and noise, use the balanced input/output feature of your ADAT-XT20. To do so, your mixer must have balanced inputs and outputs as well. The +4 dBu line inputs and outputs use an ELCO ® multipin connector.
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Chapter 3: Connections In 8 Additional grounds: ® ELCO is a registered trademark of Elco Corporation - a Kyocera Group Company Out 8 r, s, h, j, e, f, X, and Y. ADAT XT20 Reference Manual...
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NALOG NPUT The XT20 lets you choose one of three Analog Input Modes for both the Unbalanced and Balanced inputs: 2-Input Mode Input 1 feeds Tracks 1, 3, 5 and 7. Input 2 feeds Tracks 2, 4 , 6 and 8. 4-Input Mode Input 1 feeds Tracks 1 and 5.
9-pin D connector cable for each additional machine in the chain. These cables are available in various lengths from your dealer and should be Alesis-approved; improper cables (such as those used for computers) may not function correctly.
The ADAT Optical cables carry digital audio between multiple XT20s and ADATs, and to ADAT Compatible™ products such as the QuadraVerb 2, Q20, many Alesis keyboards, the ADAT-PCR computer interface card, and third-party products such as the Digidesign ADAT Interface and Yamaha 02R digital mixer.
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To connect the digital optical network: Locate the [DIGITAL IN] and [DIGITAL OUT] connectors. Remove the connectors’ plugs (if present) and store for later use. Connect one end of the fiber optic cable into the [DIGITAL OUT] jack of the first machine in the system. Remove the clear, plastic tube covering each end of the cable (if present).
Chapter 3: Connections OOTSWITCHES The XT20 provides two footswitch connectors using 1/4" mono (T/S) jacks. One, labeled [LOCATE/PLAY LRC REMOTE], allows locate and play commands when used with a standard footswitch, or more elaborate control when used with the LRC Remote control; the other, labeled [PUNCH IN/OUT ], is for punch in/out control.
HAPTER ASIC This chapter is designed for operators who may not have experience working with digital audio. All functions of the XT20 (with the exception of synchronization and digital audio) are explained here in detail. If you are already familiar with multitrack recording concepts, you may not need to read this chapter.
Chapter 4: Basic Operations Caution: If you re-format over a previously formatted tape, do not stop in the middle of re-formatting. Reason: When the tape transitions from the newly-formatted section to the previously formatted section, there will be timing discontinuities and the audio will do unpleasant things. Also, during that transition the tape will be non-functional and you will not be able to record anything over it.
The XT20 briefly enters play mode to achieve proper speed and check if the tape is formatted. The XT20 performs a complete format by recording 15 seconds of leader (the LED display will read “LEAd”), followed by two minutes of data (the LED display will read “data”), then time reference starting at -0:00:05.00 and continuing to the end of the tape.
Chapter 4: Basic Operations format mode before the end of the previously formatted section by “punching-in”. The XT20 begins “time-stamping” from the last valid time-stamp it reads from tape. This ensures continuous time-stamping when a tape plays from beginning to end. To extend the format on a partially formatted tape: Use [FAST FWD], [REWIND] and/or [PLAY] to locate to the section of tape just before where formatting was discontinued (before...
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Basic Operations: Chapter 4 Pr 0t The PROTECT icon will turn on indicating that Write-Protect is in effect. Note: This override will automatically be deactivated when you eject a tape, or turn the power off. ADAT XT20 Reference Manual...
Chapter 4: Basic Operations EADING The XT20’s display serves many functions. It shows the current level of each of the eight audio tracks, it shows the current tape position numerically in hours, minutes, seconds, and 100ths of seconds, and shows the current modes of the many parameters available.
ISPLAY The following icons appear in the display at different times. They indicate that the parameter for which they are named has been selected or turned on. These icons are: FINE dB fine calibration mode, showing the range from -18 dBFS to -12.5 dBFS instead of the normal 0 to -48 range.
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Chapter 4: Basic Operations This icon will light whenever edit mode is selected (by pressing the [EDIT VALUE] button). See page 46. Indicates that the transport is shuttling to a Locate Point (0–9). When in Edit mode, this icon indicates that you are editing a Locate Point’s address, which will appear in the TIME counter.
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Basic Operations: Chapter 4 The CLOCK group of icons indicates which clock source is being used. The [CLOCK SELECT] button lets you toggle through the various options, including: INT 48K (internal clock at 48kHz), INT 44.1K (internal clock at 44.1 kHz) and DIG (external clock source connected to the [DIGITAL IN] connector on the rear panel).
TIME C The TIME Counter (found at the top left section of the display) is used to indicate the current tape position. The [ABS/REL] button toggles the TIME counter between Absolute Time mode and Relative Time mode. The XT20 will indicate which Time mode is selected by either displaying ABS (for Absolute Time) or REL (for Relative Time) just to the left of the TIME counter.
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Chapter 4: Basic Operations automatically switches the TIME counter to Relative Time mode (if not already selected); the REL icon appears to the left of the TIME counter. The counter will now read: ADAT XT20 Reference Manual...
ASIC DITING EDIT V The [EDIT VALUE] button is used to turn Edit mode on and off. When turned on, the EDIT icon will light indicating you are now in Edit mode. At this point, you can press any one of the [LOCATE 0] - [LOCATE 9], [TAPE OFFSET] or [TRACK DELAY] Function buttons to view and/or edit their respective parameter settings in the display.
Chapter 4: Basic Operations DITING You can also select a specific digit in the display to edit, by holding the [EDIT VALUE] button and pressing either [ ] or [ ]; the currently selected digit will flash. While still holding the [EDIT VALUE] button you may press any of the [LOCATE 0] –...
NPUT ELECT There are three buttons for input select options. These three buttons are labeled [ANALOG INPUT], [DIGITAL INPUT], and [TRACK COPY]. These determine what signals will be recorded on the XT20. The currently selected input mode is indicated in the lower right corner of the display: ANALOG, DIGITAL or TRK COPY.
Chapter 4: Basic Operations In 2-input mode, inputs 3-8 are disconnected and cannot be recorded or heard. In 4-input mode, inputs 5-8 are similarly disconnected. To use all inputs, 8-input mode must be selected. IGITAL To record from the digital input, press the [DIGITAL INPUT] button; the DIGITAL icon in the INPUT icon group will light.
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• A digital source track cannot be selected as a digital destination track (i.e. digital source tracks will not be allowed to be record enabled when Track Copy is enabled). • If no source tracks are selected, you will not be able to place any tracks into record-ready.
Chapter 4: Basic Operations NPUT ONITOR The Input Monitor controls consist of two buttons: [ALL INPUT] and [AUTO INPUT]. NPUT This feature determines what you will hear from the XT20’s output jacks when a track is record-enabled (REC LED flashing): tape, or source.
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Record-enabled tracks = Transport Function Stop,Pause, Rew.,F.Fwd Play Record ADAT XT20 Reference Manual ; Tracks not record-enabled = Auto = Off Auto = On Auto = Off/On All = Off All = Off All = On = Input = Input = Input = Tape = Tape...
Chapter 4: Basic Operations ETERS The XT20 provides two buttons for meter display options: [PEAK MODE] and [PEAK CLEAR]. The [PEAK MODE] button selects the peak hold mode of the eight level meters. Each time the [PEAK MODE] button is pressed, the peak meters switch between three possible Peak Hold modes: Continuous, Momentary and Off.
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Basic Operations: Chapter 4 Note: The Peak Hold function is disabled (off) when Fine Meter mode is enabled. ADAT XT20 Reference Manual...
Chapter 4: Basic Operations ECORDING A We recommend that you format and record a new tape with any signal, such as a test tone, in a single pass with no overdubs during the first week of operation. Store this tape in a safe, dry location and don’t use it for any other purpose. Such a “benchmark”...
ECORD NABLE To record enable a track, press the track’s RECORD ENABLE button. When you press a track’s RECORD ENABLE button for the first time, the track’s red REC LED will flash, indicating the track is in record-ready, and its INPUT LED will light (unless Auto Input is on and the transport is in play), indicating you will be able to monitor that track’s input.
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Chapter 4: Basic Operations still have 15 dB of headroom on the XT20 before distortion occurs. Just remember that no matter what, if the XT20’s meters indicate over 0 dB, distortion is occurring or is on the verge of occurring. Be sure the outputs of your mixer match the inputs connected to the XT20 (+4 or - 10).
RANSPORT The XT20’s six transport control buttons resemble those of a conventional tape recorder, although there are several extra features. JECT Press the [EJECT] button to eject the tape from the XT20. If the tape is moving, it will stop before ejecting. In a multiple XT20 system where there is one master and one or more slave XT20s and/or ADATs, pressing [EJECT] on the master will eject the tapes on all machines;...
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Chapter 4: Basic Operations Pressing [FAST FWD] while holding the [PLAY] button • initiates “Cue” mode. The tape fast forwards at about 3 times normal play speed, and you can hear chunks of attenuated audio so you know where you are on the tape. The [PLAY] LED will be lit, and the [FAST FWD] LED will be flashing.
Press the [PLAY] button to play the tape ([PLAY] LED will light). The [PLAY] button by itself has no effect while playing, but it will terminate recording. While locating, pressing [PLAY] will cause the XT20 to start playing after it arrives at the corresponding tape location ([PLAY] LED will flash to indicate deferred play mode).
Chapter 4: Basic Operations • Press [PLAY]. • Hold [RECORD] , and then press [PLAY]. • Use the RECORD ENABLE buttons [1] – [8] to take tracks out of record. The [STOP] button performs three functions. • Stop the transport. Push [STOP] to stop any function involving tape motion.
the formatting process, the sample rate information is written onto the tape. This information allows the XT20 to know what sample rate the tape was originally formatted at. When inserting a tape that was formatted at 48 kHz, the XT20 reads the timecode from tape for a moment and automatically selects the 48 kHz clock setting.
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Chapter 4: Basic Operations normally uses the “hours:minutes:seconds:100ths/second” format. This may cause some confusion when locating to a specific position on the BRC, since the XT20 will show a slightly different value when looking at the last two digits of the TIME counter. The XT20 will locate to the same physical position that the BRC displays, it is simply displaying 100ths/second instead of frames.
The counter will not elapse in real time when the pitch is set to a value other than zero. • When you change the pitch on ADAT-XT20, the sampling rate will also change. The lowest sampling rate is 40.4 kHz, the highest is 50.8 kHz.
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Chapter 4: Basic Operations counter display it is better to set the pitch to 0 and change the clock rate (see page 59). ADAT XT20 Reference Manual...
RACK ELAY Track Delay lets you delay individual tracks up to 170 ms, in order to achieve a more desirable “feel.” For example, if the bass track is anticipating the beat, you can push it back so it’s “in the pocket” by delaying it a few milliseconds. If you need one track to play back earlier than the others, try offsetting all other tracks by the same amount.
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Chapter 4: Basic Operations hold one RECORD ENABLE button while pressing others you wish to adjust to the same amount, then proceed with steps through ADAT XT20 Reference Manual...
UTOLOCATION The XT20’s autolocation controls consist of 10 Locate Point memories which can be set either manually or “on the fly”, and recalled instantly. Each Locate Point’s address can be displayed and set using either Absolute or Relative Time. Generally, Absolute Time and Relative Time will differ in their values. The XT20, however, maintains a constant offset between them.
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Chapter 4: Basic Operations points represent the same actual (physical) position on tape, regardless of whether the display is in ABS or REL mode. The [LOCATE 0] button is also used to set the relative zero time. When this button is pressed while holding [SET LOCATE], the relative tape counter is reset to zero (0:00:00.00).
ETTING There are two ways of storing Locate Point memories: manually or “on the fly.” To store a Locate Point memory “on the fly”: Press [PLAY] to engage playback. Alternatively, the transport may be engaged in either Rewind, Review, Fast Forward, Cue, Record or Stop mode (i.e. the transport does not have to be in Play mode to store Locate Points in the following manner;...
If this is not to your liking, this safeguard may be disabled. This is done by holding the [SET LOCATE] button and pressing [AUTO RETURN]. However, Alesis recommends doing so only when you absolutely have no other alternative. The 100 loop limit will be enabled again once [STOP] is pressed.
ECORD The Auto Record function lets you determine exactly where recording should begin and end beforehand, so that the machine automatically takes you in and out of record. Locate Points 2 and 3 determine the in and out points. After setting both Locate Points 2 and 3, press the [AUTO REC] button to enable this function;...
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Chapter 4: Basic Operations is reached, any tracks that are in record-ready will be in input monitor mode and the [RECORD] LED will continue flashing. When the Locate Point 3 position is reached, any tracks that are in record-ready may return to tape monitor mode.
ENGTH The XT20 can take advantage of the extra recording time on tapes longer than the standard ST-120 length. You can use ST-180 tapes, for over one full hour of recording time. ST-60 tapes can also be used for shorter projects; the XT20 automatically recognizes the shorter length of the ST-60 because the hubs used in the cassette are larger.
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Chapter 4: Basic Operations If using tapes longer than the standard ST-120, when locating for the first time past the 39 minute position, the transport will slow down (but not stop) and then speed up again. Each time thereafter that you locate beyond this point, the transport will not slow down.
OOTSWITCH The XT20 provides two footswitch jacks: [LOCATE/PLAY/LRC REMOTE] and [PUNCH IN/OUT]. Both accept any momentary, single pole/single throw, 1/4- inch mono (T/S) footswitch. During power-up, the XT20 checks the footswitch to determine whether it is normally open or normally closed type, and calibrates itself accordingly.
Chapter 4: Basic Operations SING THE The XT20 hand-held LRC remote provides the following functions: • Transport functions: Rewind, Fast Forward, Stop, Play and Record. • Autolocation functions: Locate 1, Locate 2, Locate 3, Locate 4, Set Locate and Auto Loop •...
ULTIPLE XT20 O VERVIEW By itself, a single ADAT-XT20 provides a lot of flexibility. However, a multiple ADAT system greatly expands your recording and editing possibilities. Keep in mind that since the XT20 is an ADAT-compatible machine, you can intermingle any number of XT20s and other types of ADAT together—up to 16 machines total for 128 tracks (see the section entitled...
YNCHRONIZING Synchronization requires a dual male, 9-pin D connector cable for each slave to be synchronized. Use only Alesis cables. Alesis Sync Cables are available in three different lengths: 8", 30", and 30' from your dealer. Other types of cables may cause incorrect commands to be received, and erratic sync performance.
Chapter 5: Multiple ADAT-XT20 Operation achieved (indicated by the LOCKED icon being lit). Pressing [EJECT] on the master ejects all slave’s tapes as well. To eject only the master’s tape, hold [SET LOCATE] and press [EJECT] on the master. When recording or punching in on the slaves, initiate recording on the master but do not have any master tracks record-enabled (unless, of course, you need to record tracks on the master).
If the master’s FORMAT icon is on, and you are extending the format, and the slave tape is not formatted: • The slave plays, but the TIME counter reads “noFO” (no format) while flashing the FORMAT icon. ADAT XT20 Reference Manual Multiple ADAT-XT20 Operation: Chapter 5 ORMAT NABLED ORMAT XTEND...
Chapter 5: Multiple ADAT-XT20 Operation If the master’s FORMAT icon is on, and you are extending the format, and the slave tape is formatted: If the slave’s FORMAT icon is on, the slave autolocates to the • same time as the master, then format extension begins with the master.
If the [DIGITAL INPUT] button is pressed, the XT20 will record from the [DIGITAL IN] connector, and the analog inputs will be ignored (both balanced and unbalanced). Alesis’ proprietary multi-channel digital bus carries the 8 tracks of a source XT20 or ADAT. All 8 channels are sent in a one-to-one relationship to the 8 tracks of the target machine which can record the digital audio.
Chapter 5: Multiple ADAT-XT20 Operation EASSIGNING It is possible to reroute the channel/track assignments so that any incoming channel of digital audio can be recorded onto any track, or multiple tracks. This is done by first holding the [DIGITAL INPUT] button and pressing any of the RECORD ENABLE buttons [1] –...
Press all RECORD ENABLE buttons [1] – [8] on the slave XT20. The RECORD LEDs for tracks 9–16 (all eight of the slave machine’s tracks) will flash. ADAT XT20 Reference Manual Multiple ADAT-XT20 Operation: Chapter 5 IGITAL ACKUPS If you...
Chapter 5: Multiple ADAT-XT20 Operation Be sure that the RECORD ENABLE buttons are switched off for tracks 1–8 of the master XT20 and the write-protect tab (or record tab) is removed (open). Press both Since this is the master machine (ID 1), it will simply enter play (since none of its tracks are in record-ready) while engaging record on the slave machine.
Recording digital audio onto the XT20 from a source other than an ADAT-Compatible device requires a digital audio interface, like the Alesis AI-1 or Otari UFC-24. The AI-1 converts either AES/EBU or S/PDIF digital audio protocols into the Alesis Multichannel Optical protocol which the XT20 uses, and vice-versa.
Chapter 5: Multiple ADAT-XT20 Operation IGITAL When switching between the XT20’s two internal clock sample rates (48 kHz and 44.1 kHz), the reference base used for computing tape location is changed. The result is that the same tape location will appear to have two different time addresses depending on the sample rate (CLOCK) you are using.
The offset digits will remain exactly the same. However, this step will toggle between positive and negative values by either displaying a “-” or not. To reset the Tape Offset amount to 0:00:00.00, press both [ ] and [ ] simultaneously. ADAT XT20 Reference Manual Multiple ADAT-XT20 Operation: Chapter 5...
Chapter 5: Multiple ADAT-XT20 Operation OMBINING XT20 T The XT20’s transport speed has been improved to be four times faster in engaged mode than the original ADAT. Because of this and other unique features, it is recommended that you make the XT20 the master (ID 1) in your system and any ADAT(s) should be the slave(s).
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Multiple ADAT-XT20 Operation: Chapter 5 The ADAT XT20 lets you monitor the input signals through the converters at all times. Because of this, there is an extremely minimal delay as the digital audio passes through the converters’ buffers. If you...
Chapter 5: Multiple ADAT-XT20 Operation OLARITY The original ADAT was designed to invert its analog input signal internally before the audio was sent through the A/D (analog-to- digital) converter and recorded onto tape. The digital representation of the data (as stored on tape) was therefore inverted relative to the analog input (i.e., a positive voltage at the analog input is stored as a...
(or longer) to make the connection between ADATs and XT20s. This is because the [SYNC IN] and [SYNC OUT] connectors have been moved on the XT20 rear panel to the opposite side, and the shorter cables will no longer reach. ADAT XT20 Reference Manual Multiple ADAT-XT20 Operation: Chapter 5...
- out of the mix itself. This opens up all sorts of possibilities, like changing the EQ, effects and other mix settings for different sections of the mix. ADAT-XT20 Reference Manual ULTITRACK IXDOWN...
Naturally, the audio signals would need to be split and connected to both sets of inputs. If you are using an Alesis BRC with a multiple ADAT system, you can take advantage of a feature called continuous recording. By splitting the system into two (or into two sets of machines), you can offset the second set by a specific amount of time.
A common application in the audio post-production environment is locking to video using the timecode on the video tape as a source. This requires a synchronizer interface, such as the Alesis AI-2 or BRC. The connections consist of running a balanced 1/4" TRS cable between the AI-2’s [SMPTE IN] connector and the VTR’s SMPTE OUT (if timecode is recorded onto either the left or right...
ADAT-PCR C If your computer (Macintosh or Windows-compatible) features a PCI slot, consider using the Alesis ADAT-PCR to control your XT20 directly from a computer and transfer audio to and from hard-disc editing software. The ADAT-PCR is treated as “another ADAT” in the chain since it has ADAT Sync and ADAT Optical In and Out ports.
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Or, if you’re both using BRC remotes, save your setup to the “data” section of tape (this is called saving the Table of Contents, or TOC). This way, you partner can pick up right where you left off. ADAT-XT20 Reference Manual...
Press [PLAY] and [RECORD] on the slave ADAT. ALCULATING The Alesis BRC provides a way of setting tape offsets using any of the 20 Locate memories in a song. This means you can set a Locate at one point, another Locate at another position, then have one of the slave ADATs offset by the amount of time between those two Locate positions.
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To do this, press and hold the [EDIT VALUE] button and press [LOCATE 4], [LOCATE 7], [LOCATE 3] then [LOCATE 0]; then release [EDIT VALUE]. Press [EDIT VALUE] to exit Edit Mode. Press [TAPE OFFSET] to turn the Tape Offset function on. ADAT-XT20 Reference Manual Applications: Chapter 6...
(A/D) converter, a device that takes 48,000 samples or “snapshots” of the signal level every second that corresponds to its level. Analog Signal ECORDING ECORDING ASICS ASICS . Each sample is assigned a specific numeric value Digital Signal ADAT-XT20 Reference Manual...
If your application is extremely critical, it is possible to record at 24-bit resolution on your ADAT-XT20 using external adapters (i.e., the Rane PAQRAT or the Yamaha 02R). This method takes the “extra” bits and records them on higher tracks, so you won’t get eight tracks without...
PPENDIX ROUBLESHOOTING ROUBLE If you are experience problems while operating the XT20, please use the following table to locate possible causes and solutions before contacting Alesis customer service for assistance. Symptom The display does not light when the [POWER] switch is turned on.
ADAT will always be better than if your ADAT is abused, placed in bad environmental conditions and used with badly maintained tapes. Properly cared for, your heads should last for thousands of hours. OFTWARE ERSION ISPLAY RROR EADINGS ADAT-XT20 Reference Manual...
ADAT and your ADAT heads possible. ADAT H The heads of each ADAT are pre-aligned at Alesis. No user adjustment is necessary. Over the course of time, depending on the quality of the tapes used and the environmental conditions where the ADAT and its tapes are stored, head cleaning may become necessary.
Appendix B: Troubleshooting the last cleaning (see below). Call Alesis Product Support for more information about head cleaning and authorized Alesis Service Centers. The XT20 keeps track of how long the head has been actively spinning against tape (i.e., threaded in stop, or play, or cue/review). This can help determine how long it has been since the last time it was serviced or cleaned.
Service on this product should be performed only by qualified technicians. THERE ARE NO USER-SERVICEABLE PARTS INSIDE. BTAINING Before contacting Alesis, check over all your connections, and make sure you’ve read the manual. Customers in the USA: If the problem persists, call Alesis USA at 1-800-5ALESIS and request the Product Support department.
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Tape a note to the top of the unit describing the problem, include your name and a phone number where Alesis can contact you if necessary, as well as instructions on where you want the product returned. Alesis will pay for standard one-way shipping back to you on any repair covered under the terms of this warranty.
If this error message is displayed with only one tape the cassette may be at fault. If the message is displayed with several tapes, with and without labels, you should contact Alesis for service.
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Perform the automatic brake calibration (see below). If this message appears in the midst of normal operation more than once in every ten hours of operation, perform the automatic brake calibration (see "Automatic Brake Calibration Procedure", next page). ADAT-XT20 Reference Manual...
XT20. Turn the power of the XT20 off, wait a minute and then re-power the XT20. Repeat steps 1 to 3. Does the error come back? If it does, then try a different tape. Repeat steps 1 to 3. Does the problem recur? ADAT-XT20 Reference Manual RAKE ALIBRATION EFORE...
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ADAT, then either the tape is faulty or it was formatted on an out of alignment XT20 or ADAT. At this point, you should call Alesis Product Support. If the problem does not occur, and the tape works fine, then we need to look at your XT20.
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Operating Temperature: Operating Humidity: specified performance Dimensions (H x W x D): Weight: ADAT-XT20 Reference Manual Appendix D: Specifications Two EIAJ fiber optical jacks (1 in, 1 out) 8-Channel Serial Communication 90V–250V AC, 50/60 Hz 10–40° C for specified performance 80% maximum with no dew condensation for 5.25"...
A function whereby the transport automatically begins to rewind once reaching a certain point, and returns to an earlier point. The point at which rewinding begins is called the Auto Return End point. The point that is returned to is called the Auto Return Start point. IGITAL ONVERTER ADAT-XT20 Reference Manual...
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The XT20 has digital I/O connectors that carry digital data for all eight tracks. IGITAL The device that converts digital signals back into an analog format so that they can be heard. ADAT-XT20 Reference Manual IGNALS NALOG ONVERTER Glossary...
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Used as a verb, to “mute a channel” means to turn off the audio for that channel. Used as a noun, “mutes” are the buttons which turn off a particular channel. Mutes are usually non-destructive, though not always. Mutes are often automated as part of mixer automation systems. UTPUT ONNECTOR ADAT-XT20 Reference Manual...
A complete description of LTC can be found in The Time Code Handbook, by Walter Hickman. SMPTE timecode is the standard sync reference for professional audio and video post-production. S/PDIF I NTERFACE ADAT-XT20 Reference Manual ONVERSION Glossary...
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Glossary Similar to the AES/EBU interface, but created by Sony and Philips with consumer applications in mind. The optional AI-1 from Alesis offers both the consumer S/PDIF interface and professional AES/EBU format for use with the XT20. S-VHS Acronym for Super Video Home System, an improved version of VHS with greater resolution and dubbing capabilities, as well as improved sound.
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Index for crossfade time, 52 for infinite loop, 58 for Relative Time, 41 for tape length setting, 60 to eject master only, 65 to max Pitch amount, 54 to set a negative offset, 73 SET LOCATE button, 56, 57 signal level, 48 Software Version, 88 STOP button, 51 S-VHS, 11, 60, 79, 85...
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