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Doepfer Regelwerk

MIDI Fader Box & Step Sequencer By Paul Nagle
Published February 1999

Fancy having 24 assignable faders and 72 buttons to control your MIDI gear? How about an eight-track MIDI step sequencer with CV and gate outputs too? Paul Nagle explores a product that gives you both.

Doeper Regelwerk MIDI Fader box and Step Sequencer.Doepfer, the small German synth manufacturer, are probably best known for their analogue modular systems, but they also have an established pedigree in MIDI sequencing and control products, including the huge Schaltwerk trigger sequencer (reviewed SOS July 1993) and the MAQ 16/3 step sequencer (see SOS February 1998). These are now joined by the Regelwerk and (very soon) the Drehbank 'knob box'. There is a degree of overlap amongst them all, but the Regelwerk's role seems divided straight down the middle; a dual personality with no apparent hang-ups. On the one hand, it's a MIDI fader box; on the other, an analogue-style step sequencer — and both aspects can be used at the same time.

Construction Werk

The Regelwerk's sharp corners and bare metal finish strike a 'no-nonsense' pose and I only hope time will leave its bright surface untarnished. Occupying five rack spaces but only about three inches deep, this is a stylish, slender device with a generously recessed area at the rear to protect its connections. Its construction is solid enough and although the sliders feel a little lighter than those of the Peavey PC1600 MIDI fader box (which it rivals in some ways), their response is positive and smooth. Each has a 60mm throw, and with a total of 24 to play with this is either slider heaven or total overkill, depending on your needs.

The remainder of the front panel houses a 2x16-character backlit display, an alpha dial, no less than 72 small, square buttons and 56 red LEDs. Plug in the power adaptor (there's no on/off switch) and stand by for a mini version of Blackpool's Illuminations in your very own studio. If the lightshow doesn't hint that this is a serious piece of kit, a quick examination of the many connections to the outside world should. There are twin MIDI Ins and Outs, plus a DIN-Sync socket (used for interfacing with certain pre-MIDI gear and configurable to in or out) and no less than eight addressable CV and Gate mini-jack (3.5mm) outputs. The only conceivable omission is an input for a voltage pedal.

On the bottom left-hand side of the panel (if vertically mounted) is a familiar set of transport controls including start, stop, continue, tempo and so on. These buttons activate the Regelwerk's sequencer, but can also be programmed to transmit data. They are ideally suited for sending MIDI Machine Control strings (MMC is a generic SysEx protocol used to send start, stop and so on to remote devices or sequencers). Also located here is Snap Shot, a button which sends the current value of all sliders over MIDI — useful if recording their output into a program such as Cubase.

On The Menu

Unlike Doepfer's powerful but rather cryptic MAQ 16/3 sequencer, the Regelwerk has a 'proper' display. And this means menus and a lorra lorra options. The menus (there are 12 in all) are accessed from two rows of dedicated buttons in the bottom right-hand corner of the unit. Each one is documented, rather briefly, in the manual, which is divided into English and German text with the English part lagging a little behind in terms of detail. I am told that it will be fleshed out either by Doepfer themselves or by the UK distributor EMIS at some stage.

Many of the Regelwerk’s parameters are accessed and manipulated using the 2-line LCD and alpha dial.Many of the Regelwerk’s parameters are accessed and manipulated using the 2-line LCD and alpha dial.The menu buttons are small, neatly labelled and packed closely together. Repeatedly pressing each one scrolls through pages containing all the parameters which make the Regelwerk tick. Most edits are made via the alpha dial. There are +/- value keys too, but these only seem to function on a couple of pages.

Rather than look at each menu in turn, I'll refer to them as necessary whilst exploring the Regelwerk's functions. So, without further ado...

Fade To Grey

On power-up, the Regelwerk boots into Fader mode. The 24 faders and 24 switches are ready to perform automated MIDI mixing tasks or edit parameters on connected MIDI synthesizers or effects boxes. As shipped, there are no included templates, so you need to program it to do your bidding. Fortunately, this is relatively painless: first, select the fader to edit by hitting the small key directly above it. Its LED will light and the display will indicate the current status of this slider, the type of MIDI data it will send and its value. Hitting the Fader Edit menu key displays the current MIDI channel for the slider. A second press selects the type of data to send. Choose from Note On or Off events, Mono or Poly Aftertouch, Controller, Program Change, Pitch Bend, 'String' or special ('Meta') events — all you'd expect, really, with the exception that there is no means of inserting a checksum calculation.

String includes any type of MIDI data up to a maximum length of 30 bytes (to be expanded in future versions). The slider value can be referenced at any point in the string. System exclusive data is entered using a rather basic editor; after first specifying the length of the string, you then add it, an event at a time, with the alpha dial. There is no means of inserting or deleting events, so the manual advises you to write your strings out in full before entering them. This is a little long-winded but usable nonetheless — it took me a little more than an hour to make an editor for most of the parameters of my Korg EX8000 synth. Special or Meta events allow fader control of internal sequencer functions without needing to use the menus — more about this when we look at sequencing later on.

Once a fader has been defined, further options are available from the Fader Parameter menu. Here you can restrict (or even invert) the fader range and select which of the two MIDI outputs (or both) is used to send data. There are a number of ways that incoming data can interact with the fader's value — perhaps overwriting the value or disabling the fader until a certain event is received.

The faders may be set to any of three modes: Catch, Relative or Immediate. These modes are designed to get around the sudden 'jumps' that could happen when you move a slider whose position does not match its stored value. Immediate means that the value changes as soon as you touch the slider, Relative that fader value is added to the existing value and Catch means no value is output until the fader moves 'through' the stored position. There is a Catch Threshold parameter, too, which lets you place a wider 'activate zone' around the value. The net result of this choice of modes is that you can be sure of no unwanted leaps in values output by the Regelwerk, which is nice. But we haven't quite finished yet. Each slider can function as Master or Slave which, in practical terms, means you could program 16 Slave volume sliders (Control Change 7), each on separate MIDI channels, then use a Master slider to raise or lower all of them. Annoyingly, in the present version, the Master/Slave status is not stored in the Regelwerk's memories (or Presets) so you need to manually make this change every session.

If setting up sliders seem like a chore, there's a handy Learn Mode which will capture MIDI events transmitted to the Regelwerk and set them up for control by the fader of your choice. Simply transmit a SysEx string or other MIDI event and the Regelwerk will store it (subject to the 30-byte string limit) for transmission via the fader. Alternatively, simple Copy operations are provided to replicate slider events.

In addition to its assignable faders and buttons, the Regelwerk features a full set of transport controls for operating recording equipment via MIDI Machine Control. In addition to its assignable faders and buttons, the Regelwerk features a full set of transport controls for operating recording equipment via MIDI Machine Control. Once you have set up everything as you wish, be sure to save your work. A complete dump of all sliders (and switches) is called a Preset and there is space to store 64 of them in total. If that isn't sufficient, they may be transmitted as a system exclusive dump for external storage. When the Regelwerk is first plugged in, Preset 1 is loaded automatically — Presets are always referred to by their number; they cannot be named (although individual faders can). I consider this a serious omission as it reduces the selection of mixer layouts, synthesizer editors and so on to little more than trial and error, unless you keep note of which is which on a handy lo-tech piece of paper. Snapshots of fader and switch settings can also be stored and retrieved, although there's no naming facility for them either. Up to 128 snapshots may be saved.

Whilst in Fader mode, the LEDs above and below each slider serve as a kind of monitor, providing visual indication of the position of the fader relative to the stored data. If the fader needs to be moved upwards to reach the stored value, the upper LED flashes with a frequency which indicates (roughly) how far it must travel.

Under each slider is a key, a small black button, which can send data or mute the slider output. With one exception, which we'll come to later, these buttons may be designed all the same data options as sliders. The Key On Edit menu is used to set the data type and value that is sent when any of the keys are depressed. A different set of events may be sent when the key is off and you decide whether a key press should be 'momentary' (remaining on only while held down) or 'toggle' (successive presses toggle between on and off).

Sequencer Mode

Press the Sequencer Mode button and the other side of the Regelwerk's nature takes over. Well, it takes possession of sliders 9-24 and their associated buttons, anyway — the first eight always remain in Fader mode. Hit the Start key and the Regelwerk begins to step through the notes as set by each slider (see the 'Steps In Time' box if you're unfamiliar with step sequencers). A second press of the Sequencer Mode button, and the sliders now control note velocities.

The Regelwerk's sequencing power is based around the layering of up to eight tracks. Individual tracks have a length of between one and 16 steps maximum; there is no chaining facility for longer patterns, but you can run tracks of different lengths together. Each track can have its own step time based on a division of the MIDI clock pulses, and each step may have its own gate time, which specifies the duration for notes. Tracks simply run from step 1 to their end step and then start again (progress is shown by the upper row of LEDs). This means there are no fancy pendulum or random motions such as found on Doepfer's MAQ. The buttons below sliders 9-16 are now used to select which of the eight tracks is to be edited, and the eight buttons under sliders 17-24 set each track to mute or play. Individual note steps are set on or off using the upper row of buttons.

Choose a MIDI channel for each track plus a base note number. If you change this base note at any time, the track is transposed in pitch. As you move each slider, its MIDI note number (for instance, 60 for Middle C) is shown in the display. I am told that the facility to transpose tracks via MIDI note input will be included in a future version — perhaps the update will show the actual note too?

Using just these facilities, things can get quite complex quickly. More importantly, every note can be tweaked on the fly, turning the Regelwerk into a performance instrument in its own right. Doepfer suggest using the sequencer to generate drum patterns, and indeed they talk in terms of a more interactive version of the drum grid editor found in popular sequencers. Personally I found it a little robotic for all but the simplest of percussion patterns; some means of shifting tracks or notes relevant to the others would be a valuable addition. All sequence data is stored in 'Patterns' along with the sequence tempo (50-255 bpm). As in the case of Fader settings, there are 64 memory locations, referenced by number.

A pleasant surprise is the presence of 8 CV and Gate outputs, used for sequence playback only. Each output corresponds to a track, its notes generated by that track's MIDI data. So you could connect an Octave/Volt analogue synth, and sequence it happily alongside your MIDI gear from the Regelwerk. The synchronisation facilities are comprehensive: MIDI Clock information may be sent to either of the MIDI outputs, or both at the same time. The DIN-Sync socket can function as output or input; Doepfer suggest the latter as a means of "relaxing the tight tempo"; solder up an appropriate lead and you can drive everything from an LFO square wave. The sequencer sends Start, Stop and Continue commands from both MIDI outputs as default, although its transmission of real-time commands may be switched off if required. All user tailoring of Sychronisation parameters is lost on power-down, which can be a nuisance if you prefer to use the Regelwerk as clock slave or ensure no clock messages are sent via a specific MIDI output.

Available to the sliders (but not the buttons) are special 'meta events'. These control internal Regelwerk sequencer functions: pattern select, track end, track velocity, track base note, step velocity and step note. By controlling these functions from sliders, you have a much more convenient method of tweaking a track as it plays than by using the menu options. Having several tracks of differing lengths looping at the same time might be a little confusing for dance music, but it is handy when you're in a more experimental mood.

The Regelwerk has been designed so that both Fader and Sequencer modes co-exist in harmony. If you leave a sequence running then enter Fader mode, you have full access to all 24 faders without missing a beat.


Conceived originally as a fader box, the Regelwerk has evolved into much more than that with the addition of sequencing. During the course of this review I realise I've kept things rather dry and factual, attempting to list the features rather than suggest uses for them all. If your eyes glazed over long ago I apologise, but anyone interested in a piece of kit like this will no doubt have their own agenda in mind. More detail can be obtained by downloading the English version of the manual from Doepfer's web page. In fact, it was this that convinced me to break a golden rule and buy a Regelwerk without seeing it first. For me, it is an ideal source of extra MIDI controllers for my Nord Modular Synth (the Doepfer has replaced my old Peavey PC1600). It acts as clock master, runs sequences on MIDI and non-MIDI gear — but the deciding factor was, of course, its generous quota of flashing lights...

It's quite possible that for some people, the Regelwerk offers too many features. Control junkies, though, can never get enough. It's great to sequence notes and their velocities but I'd like to be able to sequence MIDI controllers too. Others may wish for the maximum length of a SysEx string to be increased or perhaps to be able to add checksum calcuations.

If you need a MIDI fader box and have any interest in sequencing, then I'd recommend the Regelwerk highly. Judged as as sequencer alone, maybe it doesn't yet have all the bells and whistles, but by layering, or switching between, eight different tracks, more options are available than appear at first. Ultimately, the Regelwerk's greatest strength is found not in a mere list of functions but in its interactivity. There's something 'real' about these physical controls that no computer screen or mouse can ever match.

Steps In Time

Step-time sequencers seem to be increasing in popularity, rather like arpeggiators, but the difference between them is worth noting. Arpeggiators generate rhythmic musical patterns based on notes that you actually play; step sequencers cycle through a series of notes the values of which are set by knobs, or in this case, sliders. The resulting 'sequence' is invariably a pattern that you wouldn't stumble upon by playing a keyboard and forms the distinctive backdrop for many electronic compositions.

Step-time sequencers (sometimes called analogue sequencers) are not to be confused with MIDI recording programs such as Cubase (which are also often referred to as sequencers); nor do they have much in common with hardware MIDI recorders such as the Yamaha QY700. Typically, the output from a step sequencer involves short, looping patterns of notes which can be manipulated extensively during playback. Tip of the day: almost all step sequences benefit when delay effects are added.

System Update

As I tested the Regelwerk, I discovered a couple of bugs either with features which only partially worked or which didn't work at all. Apparently, these are known to Doepfer and fixes are planned for February 1999. However, since the operating system is stored in EPROM, this will necessitate opening up and replacing the chip when the bugs have been hunted down — sadly, Flash ROM was deemed prohibitively expensive.


  • 24 sliders and buttons, assignable to whatever you wish.
  • Step sequencer and fader modes work in parallel.
  • Triggers non-MIDI equipment too.
  • Looks great in the dark!


  • No names for fader presets, sequencer patterns or snapshots.
  • Some bugs.
  • Fixes and new features require EPROM replacement.


An impressive collection of facilities for the money. As a fader box, it offers more controls per pound than the competition and as a step‑time sequencer it offers eight simultaneous tracks of 16 steps. There are a few bugs to iron out but they're not show-stoppers.


£449 including VAT.

EMIS +44 (0)117 956 1855.