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What's In The Bokse?

Bokse SM-9 Timecode Event Controller

How do they manage to pack so many wonderful facilities into a 19" box? Paul Gilby sets the tempo, stripes the tape and explains why this MIDI/SMPTE synchroniser is a godsend to any studio.

With the growing popularity of timecode application in music, the idea of total control at every stage of a recording takes a giant leap forward with the introduction of the SM-9 from Bokse. Paul Gilby discovers the power behind the buttons.

The union of SMPTE and MIDI code in a single box is already manifest in several products from the major equipment manufacturers of the world. First Roland introduced the SBX-80 Sync Box which enabled SMPTE timecode to be recorded onto tape and then converted back to MIDI timing data, to allow precise control of a drum machine or sequencer's tempo. It also featured one programmable cue point for starting a MIDI instrument at a predetermined time. Next came the Fostex 4050 Autolocator which incorporated SMPTE to MIDI control and bundled them together with tape machine transport functions...

Now the Bokse SM-9 has finally arrived offering a similar range of time and MIDI related control with a total of 128 cue points for £829. Not only is it cheaper than both its competitors but it's also far more powerful.


The SM-9 is divided into two parts: the SMPTE timecode Generate/Read section and the Event control section. Four timecode standards are provided, with the unit defaulting to 25frames per second, though the other rates of 24 fps, 30 fps and 30 'drop frame' are easily called up.

Timecode input and output is via jack sockets on the rear panel and these should be connected to your tape recorder ready to 'stripe' (record the timecode) an edge track of the tape with code before commencing a recording session. Once the tape has been striped you can switch the SM-9 to 'Read' and the unit will decode the signal and display the time. What appears to be a unique feature of the SM-9 is its ability to both read and write timecode simultaneously. This enables 'repair jobs' to be done on damaged code tracks by reading up to the point of damage and then recording the new code over that section. Another clever little trick is the possibility of 'stand alone' use in a situation where you want to do trial runs to rehearse synth parts for example, but without having to keep playing the tape through.

One other important point is that when in 'Read' mode the SM-9 will follow the recorded timecode over tape speed variations up to +/-30%, so you have no worries about adding acoustic instruments that need to be tuned to existing tracks by using the tape machine's vari-speed control. These Bokse people have thought of everything.

Now, because SMPTE data has been recorded onto tape, every event will have a unique time which is displayed in hours, minutes, seconds and frames on the front panel. In Britain we use 25 frames per second as this relates to the 50 hertz mains frequency and the television frame rate and is often called EBU code. This means that any musical event can be timed to an accuracy of 1/25th of a second, that's 40 milliseconds.

However, as we shall see, it is more useful to relate this timing data to a musical note length.


The second part of the SM-9 deals with the programming of events and this is split into four sections labelled Cue A, B, C, and D. Each cue can store 32 different event start and stop points, giving a total of 128 event cues - that beats just about everything else on offer at this price.

In order to use the event controller, the SM-9 must first be programmed with a Tempo Start time. This is used as the reference point to which all cues are related and can be set at any time location, so that as you progress along the length of the tape recording each new song, you can set the next song start point at whatever time you want. A brief example would be to start recording the first song on the tape near to zero hours, minutes and seconds, then if the song lasts for around five minutes, you could start the next song from the six minute position by incrementing the Tempo Start time to give the required display. It is very important when using timecode to maintain a point of reference at all times or else all cue points will be meaningless.

Once a Tempo Start time has been set you're ready to control any MIDI drum machine, sequencer or effects units, as well as non-MIDI equipment that runs off trigger pulses, for the SM-9 provides both MIDI and trigger voltage outputs.

Let us imagine that we need to synchronise a drum machine to tape. Having striped the tape and programmed the drum machine to accept external MIDI timing data, you must then set the SM-9 Tempo Start time and also programme in the song tempo in beats per minute (the SM-9 defaults to 100bpm and has a range of 30 to 254bpm). If you roll the tape the drum machine will now start playing from the Tempo Start time which could be set for 10 seconds in. Stop the tape machine and the drum machine stops to; rewind the tape a little and then on pressing Play again, the timecode readout will have moved back to the point where you rewound and the drum machine will also have moved back to the correct beat. This, however, is only true of drum machines which understand MIDI Song Position Pointers as they can auto-locate to any position in the drum pattern on receipt of the correct MIDI Pointer data from the SM-9. The practical result of this means that you can travel up and down the length of the tape wherever you wish and the drum machine or sequencer will always stay perfectly in sync and play from the right beat at the correct tempo.

This sort of flexibility is not available from more crude sync track systems as you invariably have to rewind to the beginning of the tape and start all over again each time. For the SM-9, this sort of stop/start control represents one of its most basic functions, which saves you both time and relieves the tedium of trying to get the drum machine in-sync.

Having established the usefulness of SMPTE conversion to MIDI timing data, the use of Cues is next on the list...


Cue A on the SM-9 enables you to programme a point in time where you wish MIDI timing data to start and where you wish it to stop. You can have a maximum of 32 cues and these are stored in order of execution. There are two ways of programming a cue, either by incrementing the display to a given time, or by tapping a button in real-time at the point in the music where you want an event to happen.

This last method is perhaps a more natural one and has a variable correction factor attached to it to help you hit the beat! The default setting is for a quarter note ie. it will initiate the event on the next quarter note after the point where you hit the button. Alternatively, you can programme it for eighth or sixteenth note correction, or even more precisely by second and frame editing.

So, no matter where you want an event to occur, you can tap it in and if it's not in the right place you can move it precisely to the point you want it. What's more, you can do this for all 32 cue point start and stop times, with all cues remaining 'live' and continuously editable so that you can listen to the music, find an event that's not quite at the right point, stop the tape, edit the cue and roll again to hear the result. It's very simple, dead easy to use and gives you superb control over event timing.

You can use Cue A to trigger MIDI devices to drop in and out of the mix eg. record a bass sequence at the beginning of a song and then repeat it at the end. Or you can utilise the SM-9's other two outputs: one for activating units that trigger off 'contact closures' and the other for units that require a positive 5 volt trigger like many older analogue synth/sequencer systems.

As we're on the subject of MIDI, we'll jump to Cue D. Like Cue A, this has 32 cue points but this time they are designed for programming MIDI Program Change data. Three parameters need to be set per cue: the MIDI Program number (0 to 127), MIDI Channel (1 to 16) and the time at which the change occurs. Again, like Cue A each separate cue can be edited as required.

Creatively, the use of programmable MIDI Program Changes opens up a whole field of possibilities for totally synchronised effects during mixdown, leaving your hands free to balance the sound. You can, for example, control something like the Alesis MIDIVERB to change reverb characteristics at different points in a song, even on every beat if you want to - the scope is fantastic. This sort of control over MIDI Program Change was one of the major deficiencies of the Roland SBX-80 as you could only integrate them by recording such data via a MIDI sequencer. Here Bokse give you total control over this important MIDI parameter.

Finally, in keeping with Cue A, Cue D also has two further non-MIDI outputs which trigger momentarily and in time with the MIDI data.

Last of all are Cue B and Cue C which are both identical and again have 32 programmable cue points each. The application of these cues has been tailored to provide 'gated' stop/start of any incoming clock pulses within the frequency range DC to 1MHz. This will allow you to feed the desired clock pulse rate from some other source into the Cue B or C front panel socket and back out again to control a non-MIDI drum machine or sequencer. To use the facility, you programme a cue start point and the gate opens and lets the clock pulses through until a cue stop is received. This permits other units to be stopped and started in sync with the timecode coming off tape. A simple idea that allows much of the older type non-MIDI equipment to remain part of your studio system, instead of becoming obsolete.


So far we've discussed how after striping a tape with timecode, you could read back the code and synchronise a MIDI drum machine or sequencer to the tape and trigger events at different points within a song. If you recall the section where the Tempo Start time was programmed, the option was also available to define the tempo in bpm. The SM-9 does in fact allow you to programme up to 64 changes of tempo throughout a given song. This is a very valuable control function, for when a MIDI drum machine's tempo resorts to external control, any tempo changes that you have programmed into its memory will be ineffective, therefore these need to be restored by programming the new master clock, which in our case is the Bokse SM-9.

Programming tempo changes is simple, all you do is select the Tempo parameter and the display will show the tempo in bpm for the Tempo Start time previously programmed eg. 100 bpm. It also shows 'T-1', which means you're looking at the first tempo memory, as well as the number of quarter notes that the tempo is programmed to play for. By incrementing the memory to T-2, you can change the tempo and speed it up to say 120 bpm, then define however many quarter notes the tempo is to last. You can do this throughout a song and you don't even need to set the duration of the last tempo as the SM-9 will run it automatically to the end of the song.

The only drawback is that you have to calculate how many quarter notes it is to any given tempo change in a song. However, most drum machines display bar numbers, so it isn't too difficult to work it out.

If your interest lies in film music and you are looking for a means of synchronising a drum machine to follow the pace of some visual action, the SM-9 gives you the option to display the tempo as frames per beat, which is an invaluable feature that offers a lot of potential and Bokse must be commended for including it.


There are several details pertaining to each section of the SM-9 which are better explained now.

First, when editing a cue start or stop time, you might well inadvertently try and enter a new time that in effect overlaps with a cue already programmed. In this situation, the SM-9 warns you that you are trying to write an illegal cue time by flashing the whole display. It's a nice feature.

When controlling a MIDI drum machine or sequencer it is usual to play them in what is known as 'Continue' mode. This means that when they are told to stop and start by Cue A events, they will start from the same point or auto-locate to a new point in the pattern depending on whether the timecode starts from the same point it stopped at or you've wound the timecoded tape on elsewhere. If, however, you select 'Start' instead of 'Continue', the drum machine will start from the beginning of the pattern each time you stop and re-start the tape. The point of offering this selection is tied in with the fact that some systems don't implement MIDI Song Position Pointers and it's often a case that you want to repeat a short phrase on the sequencer at different points in a song. This option allows you to do that.

When it comes down to micro adjustment of the Tempo Start position, the SM-9 features an 'Offset' function which allows you to shift the start time within a period of one frame by divisions of 1/80th (0.5 milliseconds) of a frame. You can therefore accurately align a series of events to occur perfectly on time. The practical application of the Offset facility is obvious for cueing up to visual events when the SM-9 is used as part of an A-V production set-up. However, for purely musical applications, Offset allows you to quickly produce delay effects by first recording a sequencer on tape and then re-recording on another track the same sequence having adjusted the Offset time to space it apart from the original track. You can alter the delay time to be plus or minus the original start time and so create pre-or post echo effects.

As MIDI forms an important aspect of the SM-9, additional MIDI sockets are available on the rear of the unit for MIDI In and Thru. The MIDI In socket also provides a very special MIDI Merge function where note data from a keyboard connected to the socket can be mixed with the MIDI timing data being generated by the SM-9. This is particularly important for applications where a MIDI sequencer is being used, as they rarely have the ability to merge MIDI data.

If more than one device is required to be synchronised to a master timecode readout, the SM-9 also provides a SMPTE Thru socket that outputs a cleaned-up version of the code coming off tape. This will allow video machines to be locked to the audio via an appropriate synchroniser.

Finally, having spent several hours programming cue points and recording your music, it would be a pity to lose all that data when you switched the system power off - don't fear. The SM-9 has a data save facility which dumps all the settings onto tape through the SMPTE Generate output. So, after you've finished a session you can save the data ready for re-loading into the SM-9 next time around. And if you do this at the end of each song track, you'll always know where the relevant data is on tape. It is advisable though to save it to a different track to avoid recording over the time code.


There is a feeling about the Bokse SM-9 that seems to tell you it's good, even before you switch it on! It's strange how some pieces of equipment possess that quality...

Without doubt, the SM-9 currently has no competition if you're looking for a professional aid to recording your music. The use of SMPTE timecode synchronisation to MIDI becomes invigorating with a unit such as this, for the sheer power and flexibility on offer from the 128 programmable cue points and the ability to continuously vary tempo, is akin to having all your prayers answered in one fell swoop!

This is one of those pieces of equipment that changes your whole approach to recording music. But if your needs lie equally in video post-production or live work, then the SM-9 offers just as much. In A-V tape to slide presentations, you can programme slide changes via the Cue memories, or activate lights and special effect powder flashes from the trigger out pulses for more theatrical applications, all in perfect sync with the sound. And for studio work a separate remote control unit, the RC1, is also available which will sit neatly on top of most mixers.

Finally, the only thing left to say is that the Bokse SM-9 doesn't seem to have any weak points and is an excellent example of current technology creatively applied to music.

The SM-9 costs £829 and the RC1 Remote Control £365 - both including VAT.

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Also featuring gear in this article

Previous Article in this issue

Just Can't Stop

Next article in this issue

Talking MIDI

Sound On Sound - Copyright: SOS Publications Ltd.
The contents of this magazine are re-published here with the kind permission of SOS Publications Ltd.


Sound On Sound - Aug 1986

Donated & scanned by: Mike Gorman

Gear in this article:

Synchroniser > Bokse > SM-9

Review by Paul Gilby

Previous article in this issue:

> Just Can't Stop

Next article in this issue:

> Talking MIDI

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