Orla DSE-24 & 12 Dynamic Sound Expander (1980?)

Italian FM expander from the eighties rebranded from the German model Böhm 12/24 originally based on Yamaha FM chips.

There are 2 rackmount models:
- DSE 24: voices polyphony
- DSE 12: voices polyphony.
There are 2 DSE versions with different design: a black one and a grey one.

Note: we do sold this machine long time ago, if you want to add something or some contribution (patch, sounds, documents) just drop us a line.

RACKMOUNT a single unit. Main panel features a simple segments display, 15 buttons and 1 volume knob. NOTE: all available synthesis functions are printed above the rack.

Back panel terminal connectors:
- master out
- Midi interface
- tape interface
- footswitch input for patch increase.

VOICE up to 24 voices polyphony which hardware is based on Yamaha YM chips:
- 4 oscillators operators
- 8 connection diagram algorithms (LIST DIAGRAM).

 

FM SYNTHESIS concept is close to 4OP Yamaha TX-81Z concept but with only sinewave and thus no harmonic variations.
There are 4 sinewave operators organized as algorithms, assigned as carrier or modulator linked between them on different pathways interacting on their harmonic contents depending on the variable feedback strength.
- carrier: defines the amplitude and the spectral frequency
- modulator: sets the sound timbre and the relative harmonic contents.
The module offers 8 algorithms with frequency ratio or fixed frequency: the output is fed back to its input with 7 different levels feedback, as general rule: high values feedback results in richer harmonic contents.

LFO 2 delayed modulators with variable depth amount and 2 destinations:
- LFO amplitude
- LFO pitch.

ENVELOPE up to 5 EGs:
- 1 EG for each OP: 4 segments +1 sustain time
- 1 EG pitch and 7 preset templates
- EG scaling tracking amplitude on lower or higher octaves.

PERFORMANCE up to 16 parts with some functions:
- monophonic mode with glide option
- voices stack
- detune mode.



EFFECT internal analog chorus based on BBD TDA 1022.

MEMORY machines exists in 2 different OS versions (ROM sets):
- 1 bank of 100 patches
- 2 banks of 100patches.
MIDI implementation responds to Midi System Exclusives dump.

EDITOR not much around:
- UNIMAN for Atari ST (pic below):

RELATED FAMILY:

	Bohm Dynamic DSE-24 Original German version... the same.
	ORLA DSE-9 seems to be a half rack module. Still with 4 OP structure VIDEO

 

 

VST PLUGIN / SAMPLED VERSION nothing directly related to Orla or Bohm, but galore of free FM VST and commercial samples set:

name price download demo -DEXED -MDA DX10 -OXE FM SYNTH -VX7 -HEXTER free VST

 

AUDIO DEMO

HYDROGENE FM DEMO demo by Alessandro Petrini

 

VIDEO CLIP SELECTION Böhm 12/24 synthesizer

 

 

 

 

-DSE12 / DSE24 manual and schematics

DSE ALGORITHM enlarge