by Bennet Spielvogel and Eddie Ciletti

plus, a sidebar by Jeff Klopmeyer of Alesis Corporation

Unless you've been in jail, under heavy sedation or on an uncharted pacific island, it's possible you've missed one of the most significant developments in audio recording. Weíre not talking about self-adjusting, color-coded guitar picks or some quirky retro processing unit. The machine that knocked the entire industry for a wicked loop is, of course, the Alesis ADAT.

Over seventy thousand ADAT-compatible machines have been sold ó quite alot for our industry ó the Adat being single-handedly responsible for bumping most of the narrow-format analog multitracks into the "home/hobbyist" category. The XT is likely to have a similar effect on the Original Formula "OF" Adat ó hence this article ó which offers a few ways to evaluate a used Classic.


The earliest ADATs are easy to recognize, the ADAT logo on the upper right is blue black and silk-screened onto the faceplate. (The Fostex RD-8 is basically an Original Adat with built-in SMPTE time code.) In May 1994, Alesis went to a silver plastic logo that is glued onto the faceplate. These machines delineate the transition from firmware version 3.xx to 4.0, which gave users extended features like increased record/playback times (from 40 minutes to over 60 minutes).

To check the firmware version: Hold the "SET LOCATE" key and press "FAST FORWARD." The current firmware level appears on the LCD. All black-faced ADATs can be upgraded to the most current firmware (version 4.03) but donít expect any of them to do "Jolson."

Note: Alesis ceased production of their "Classic" in November 1995.


Once you've located some likely suspects you can narrow your choices by following this advice:

Consider the overall appearance. The ADAT chassis is constructed from sheet metal to which the transport is mounted. Severe mechanical damage to the external case and/or a warped front panel is cause for closer scrutiny and may possibly be a disqualifying factor. (The XT uses a die-cast chassis which is extremely resistant to "warp factors.") Most Adat top and bottom panels get scratched from being swapped in and out of racks. It ainít pretty, but it doesnít affect performance.

Check the mileage by pressing "SET LOCATE" and "STOP." The number on the alpha-numeric display indicates how many hours the tape has been in contact with the rotary heads. Thus "0060" means sixty hours of contact while "4234" indicates over four thousand hours. Expect to pay more for machines showing less hours.


There are at least three categories of Adat sellers:

1.) People who have been heavily using their Adats and are switching to XTs for their increased wind and lock-up speeds.

2.) People who need the Adat for compatibility with the outside world, but do most of their work via MIDI and hard disk.

3.) People who thought they would use the Adat more but never got 'round to it.

The bottom line? An ADAT that's been on a schedule of regular preventive maintenance should chug along quite nicely. From all sellers, ask for the Operatorís Manual (itís worth having), the LRC (Little Remote Control), optical and sync cables (if possible) and copies of maintenance receipts (if available).

User #1 is likely to have lots of head hours but the machine should have up-to-date firmware and hardware.

User #2 will have less time on the drum, the machine should look pretty good, be up to the latest firmware but may need routine maintenance.

User #3 will have minimal head hours, but the machine should be checked by Alesis and/or a qualified tech for firmware, circuit board revisions, the type of head and related peripherals. A single machine, running version 3.04 firmware (for example) may behave well alone but may not be a team player when asked to lock-up with other machines. Multiple machines should all be running the same version. (More on Team Spirit in a moment...)


If the seller will pop the cover, check the area around the rubber tire (between the two reel tables) for shedding. Check the pinch roller to see if it looks "glazed" and be sure the capstan is clean and shiny, not encrusted with tape oxide remnants. If necessary, use a cloth dampened with Low-moisture alcohol to clean the capstan. Avoid excessive saturation because alcohol will dissolve the lubricant in the capstan bearing. For rubber parts, use Athan ATH-500-CS (415-589-5206) or a water-based cleaner, such as Windex.

Before your purchase, contact Alesis technical support at 310-841-2272 for the nearest service centers in your area. Compare service charges and turn-around times. Get a serial number and confirm the unitís age with Alesis. (This may also weed out possible "hot" boxes.) The primary Adat intermittent problem is due to a dirty Mode switch. If there are no service records for the past year and a half, get on the good foot by having the switch and all rubber parts (including belts) replaced.


Here are a couple of basic tests to determine transport condition:

Remove the top cover of the ADAT and load a tape. Once the tape is wrapped around the drum (called the engaged mode) check basic transport functions such as Play, Fast Forward and Rewind. Watch the tape as it moves around the guides and through the capstan and pinch roller. (You should eventually get familiar with what "normal" looks like.) Tape movement should be smooth and there should be no slack during fast wind or spillage during stop.

For example, press Rewind in the middle of a tape and watch the take-up side. Look for slack as the machine gets up to speed. Now press Stop (no slack or loops) and then press Stop again. The tape should disengage from the head drum assembly. Press Fast Forward (the tape is still disengaged from the head) and look for smooth travel from the supply to the take-up reel. Try these exercises at the beginning, middle and end of the tape, looking for consistent performance at each location.

NOTE: If the supply and take up reels do not come to a complete stop, the brake solenoids are either out of adjustment or have failed. If tape continues to be pulled out of the cassette shell in "Stop" mode, the pinch roller may not be sufficiently clearing the capstan. A minor adjustment could be all thatís required, but an intermittent problem is more likely Mode switch related.


Loud mechanical sounds during fast forward or rewind are minor problems that can be resolved by lubricating the impedance and tachometer rollers or by replacing the tachometer belt. (See Bennetís August Ď95 "ADAT in the Trenches" and Eddie's October Ď96 maintenance column.)


If problems are noticed toward the end of a reel, suspect either supply tension, take-up tension or pinch roller pressure. Fast forward to about 35:00 minutes and save that as Locate 1. Fast forward to about 38:00 minutes and press Set Locate 2. Use the Auto 2 > 1 and Auto Play features to continuously run this loop. The tape should be formatted, signal should have been recorded on all tracks and you should also punch in on each track during the loop. (A portable CD player can be your source and any mixer or amp with a headphone output can be used for monitoring.)

If the error display decimal lights up after repeated loops, either performance is marginal, damage is being done to the tape OR the tape itself is at fault. There should be no analog distortion when the machine is in "Input" mode or digital noise at the punch-in/out points. If the machine passes these tests, it is in good working order as a "soloist."


This last Adat test is for system compatibility ó how the machine gets along with others. For consistent lock-ups, it is important that each machine get to the locate point at the same time, otherwise a slacker will hold up the rest of the system. When the Adat is in unthreaded, fast-wind mode, the tape counter relies on information received from a reel-table tachometer. (In threaded fast-wind modes, it is able to accurately read time code information from tape.) A major difference between tachometer "predictions" and tape-accurate code will cause lock-ups to be sluggish.

  1. Format two new tapes, of the same length, brand and batch.
  2. Label one Master and the other, Slave.
  3. Connect only two machines at a time using an officially-sanctioned sync cable.
  4. Power up the last machine first.
  5. Insert tapes into their respective machines.
  6. Press "Locate Zero" on the Master. (Slave should follow.)
  7. In unthreaded mode (Press "STOP" twice), FF to 10 minutes and stop.
  8. In threaded/engaged mode, each machine should be within twenty seconds of actual tape time.
  9. Set Locate 1 at ten minutes, then FF in unthreaded mode to forty minutes.
  10. Stopped units should be within thirty seconds of actual tape time.
  11. Set Locate 2 at forty minutes, then Locate Zero in unthreaded mode.
  12. There should be 15 seconds or less difference.
  13. For machines that fall within spec, make fastest/least-hours machine the last unit in the chain.
  14. The best medicine for out-of-spec machines is to schedule maintenance for "The Team." Take all the machines to one technician (at the same time) so that performance can be optimized.
The above test does not apply to the XT


Knowing the cost of routine service should be a tool that can be used during the bargaining process as well as a reality that should be factored into all tape-based systems. Perhaps before you start shopping, it wouldnít hurt to make friends with your local service facilities and...

Take a Technician To Lunch!


The difference between the cassette-based digital multitracks and analog tape recorders is the helical scanning (rotary) head. The format was originally designed for video recording and modified for digital audio. That eight tracks can be recorded on S-VHS or Hi-8 tapes is amazing enough but that the machines can also be daisy chained for additional tracks is icing on the cake. Both formats support a full-featured remote control ó the "BRC" and the RC-848 ó the former controls all decks plus includes a SMPTE time code interface. (An optional SY-88 card adds SMPTE capability to the DA-88.) Almost any music store or recording supply business can give you an extensive demo.

With analog machines, tape speed, noise reduction (if used) and alignment (easily checked with an oscillator and VU meter) are variations based on a common magnetic concept. For example, if you put a quarter-inch stereo recording on an eight-track deck, sound will come out. There are, however, several digital formats, none of which are even remotely compatible and all being much more elusive to the process of interrogation. The closest thing to a VU meter is an error rate display and often this is only a blinking LED.

SIDEBAR: By Jeff Klopmeyer, Alesis Corporation

Whether you've just purchased a pre-owned ADAT or have been using ADAT for years, there is no better way to ensure its long-term reliability than to have it regularly maintained by a professional service center that's been authorized by Alesis for ADAT servicing.

Over the past two years, Alesis has made great efforts to make maintenance and repair of our gear as quick and easy as possible. The first step in providing great service has been the massive improvement of our Technical Support phone system. Four years ago, you might expect to stay on hold for twenty to thirty minutes (or more) before getting through to a tech. Right now, these hold times average less than six minutes, due to our state-of-the-art automated phone system and the addition of several full-time Technical Specialists. Plus, we've reinstated our toll-free number (800-5-ALESIS) for calls relating to service issues, and opened up email communication for this purpose as well (

The second step is the expansion of our extensive nationwide network of authorized service centers. In addition to Alesis' in-house service team, there are now 43 authorized centers in the domestic USA alone. Each of these centers can provide warranty or non-warranty service on ADATs. By providing such a large number of service options, the workload of each center has lightened considerably, making turn-around time for service and maintenance much faster than it was just a few years back.

What does "regular ADAT maintenance" mean? Alesis and its service centers have a set of guidelines that will tell you when your ADAT is due for maintenance. Much like changing your car's oil every 3000 miles, regular ADAT maintenance helps to avoid bigger, more costly problems later on. Even if you think your ADAT is performing normally, hold the SET LOCATE button and then press STOP to check the head-on hours. Be sure to ask the ADAT's previous owner about its maintenance records, then look at the guidelines below to determine the necessity of servicing the unit.

By following these simple, relatively inexpensive procedures, your ADAT can stay in tip-top condition for years and years to come. Contact Alesis for specific information on service center locations, turn-around times and costs of these recommended maintenance procedures. Alesis has made our post-sale product support a huge priority, but we always want to strive towards our goal of offering the best service support available in the professional audio industry. If you have any suggestions on how we can improve our capabilities in this area, please let us know.

I love feedback in the form of email.

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