Doepfer A-198 Trautonium Manual / Ribbon Controller
Module A-198 is a Trautonium Manual resp. Ribbon Controller. The controlling element of the A-198 is a linear position sensor (length about 50 cm) that has available a pressure sensor too.
Touching the sensor with a finger generates a control voltage CV1 that is proportional to the position of the finger. The scale (i.e. the relation between position difference and voltage difference) is adjustable with a potentiometer at the front panel. A hold switch is used to determine if the CV voltage is held after removing the finger (hold = on) or if the CV voltage jumps to 0V (hold = off). In the last case (hold = off) a gate signal is derived from the CV voltage whenever a finger touches the sensor (e.g. for triggering an envelope generator).
A sensitive pressure sensor located below the position sensor generates a second control voltage CV2 that increases with higher pressure of the finger. Even for CV2 the scale is adjustable. A second gate signal is triggered as soon as the pressure exceeds a certain value. The gate threshold is adjustable at the front panel.
The sensors are located in a separate metal frame (length about 600 mm, width about 30 mm, height about 18 mm, weight: about 900 g, color: silver-grey). The connection between the module and the sensor frame is made by a 4 pin cable (same as used for USB connections).
Typical applications:
Trautonium manual, the string is replaced by the position sensor that is much easier to use and cheaper than the string. In combination with the Subharmonic Oscillator A-113, the Trautonium Filter A-104 and some auxiliary modules a complete Trautonium replica may be realized. In combination with the Quantizer A-156 exact semitone intervals are possible. More details about the Trautonium principles are available on our web site (use this link: The Trautonium project).
Ribbon Controller for any A-100 parameter (e.g. pitch, filter frequency, loudness, panorama, speed, modulation depth and so on)
The English user's manual is available on our web site as pdf file: A198_man.pdf (~ 200 kB).
We have available some mp3 sound examples that were made by our Italian A-100 user Enrico Cosimione (ecosimi@chitarre.com). He plays very virtuoso on the A-198. Even some well known musical phrases of Oskar Sala are among the examples. Only these modules are used: A-198, A-110 (VCO), A-122 (24dB low pass filter) and A-123 (24dB high pass filter). No quantizer, no VCA or other modules are used, only a bit of reverb is added. The following sound examples are available:
a198_free_scales.mp3 (~ 350kB): This is an example of playing the ribbon with four fingers of right hand, alternating tapping and sliding; I have used a A-110 with PWM put into the 122 and 123 just for cut a little bit of bass click noise on finger lift-off.
a198_salas_theme.mp3 (~ 430kB): Is obviously the beginning of glissando caprice; I'm not sure that mine is the correct tonality..., I have scaled the ribbon CV to very LARGE interval, just for sake of note centering :-)
a198_scales_gliss.mp3 (~ 750kB): The position CV goes to A-110, the pressure CV goes to A-122 cutoff frequency; no quantizing, obviously; you can hear the passages between tapping (furiously) and sliding.
Remark: R2M (Ribbon-to-Midi) is the stand-alone version of the A-198 with MIDI and CV/Gate outputs. R2M offers a lot more features than the A-198 (e.g. quantizing, gate function even in the hold mode, inverse scaling and many more). R2M is available even without manual so that an existing A-198 manual can be used. For details please refer to the R2M information.
Remark (valid only for the old version of the pressure sensor used until 2005): This pressure sensor was made with conductive rubber located below the position sensor and worked not as accurate as the very precise position sensor. The resistance of the conductive rubber changed with varying pressure and caused a variable voltage. But the coherence between pressure and resistance/voltage was not very accurate - except that an increasing pressure caused an increasing voltage. Even some difference of the pressure sensor behaviour over the length of the manual was possible as the conductive rubber had tolerances over this length. From 2005 the A-198/R2M manual is equipped with a much more sensible pressure sensor and the improved sensor works even along the entire manual. Details can be found in the R2M information.
Width (module): 8 TE / 8 HP / 40.3 mm
Depth (module): 40 mm
Current (module + manual): 40 mA
Manual measures: about 600 x 30 x 18 mm (without covering cap) / about 600 x 30 x 30 mm (with covering cap at the right end)
