Kawai / Teisco SX240 with Tauntek OS & New Memory Battery

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via this Reverb listing

Full Tuantek info & specs below.

"Very nice condition clean Kawai SX-240 with Tauntek OS and new CR2032 Lithium button cell battery installed. Works like a charm! Priced right unlike some exaggerated overpriced reverb ads you see.

This is the synth playfully known as the "Juno killer", it has Bob Grieb's Tauntek OS installed which I obtained directly from him which gives the synth a lot more abilities including SYSEX and CC control! Yes, you can load/save using SYSEX NOW! It also lets you choose separate midi channels for the split/dual mode! (see below). The synth has a built in sequencer too and can be MIDI CLOCK SYNC'ed as well as the old school FSK tone clock sync. This Sx240 has decent end cheeks too, not perfect but they are decent. Most have end cheeks that are all bashed up or worse. Make no mistake, although digitally controlled, this synth is an analog monster! It utilizes SSM-2044 filter chips! This synth is ready to play now! Just plug in and play!

The SX-240 has a big, wide and full analog sound, courtesy of its two analog DCOs and one sub-osc per voice. You have the options of poly-8, poly-4 and mono modes. In mono mode it is possible to have all 24 oscillators stacked into one for an extremely powerful sound. Leads, basses, brass, drones, pads and strings all have a unique analog sound on the SX-240. Strings and pads get especially warm and fluid when switching on the Ensemble effect, which is just a chorus. The SX-240 also has a function called Brass, which is actually a ring-mod effect.

Programming is super easy using a dedicated data-wheel to edit the values of selected parameters. Four scroll buttons allow you to select the parameter you wish to edit. All the parameters have an LED light on the right hand side of the face of the SX-240 to make it very easy to see what you're editing, though only one parameter can be edited at a time. Saving your edited sounds is very easy thanks to a huge electroluminescent display and using the keys of the keyboard to type the name of your edited sound alphanumerically.

SYNTH QUICK SPECS:
Polyphony - 8 voices
Multitimbral - Dual or Split (assignable voices for each split too)
Oscillators - 2 DCOs and 1 Sub-oscillator
Waveforms - Saw, Sine and Pulse with PW and PWM
LFO - 1 LFO with 3 waveforms: saw, square and tri. Speed, Delay, Reverse and Depth controls. Can modulate the DCOs, VCA, or VCF.
Filter - 24 dB/oct four-pole Lowpass with resonance, cutoff, envelope amount and dedicated ADSR envelope generator
Envelope - 1 VCA with HPF and ADSR envelope
Effects - Chorus, Hold, Portamento and Glissando
Sequencer - 1,500 note max / up to 8 songs
Keyboard - 61 keys
Memory - 48 Tone memories. Sequencer has 8 memories.
Control - MIDI In/Out/Thru
Date Produced - 1984

TAUNTEK OS INFO:
MIDI channel can be set by pressing number switches 1-8 while powering up the synth. If Bank switch A is also pressed, it adds 8 to whatever number is pressed. The new firmware saves this setting in NVRAM, and will display it on power up. To return to OMNI mode, press any number switch and also Bank B switch, while powering up the synth.

When Tape Enable is activated, two new number LED's will flash. Pressing 4 will transmit all programs out on MIDI. Each one is a complete sysex block, which contains the program number. When that block is sent back to the SX-240, the program number determines where it is stored. Pressing 3 will transmit all 8 sequence memory areas out on MIDI. It also sends a smaller area of memory which holds other sequence-related data. When either the programs or the sequences are loaded into the SX-240 over MIDI, the Memory Protect switch must be in the "Release" position. While the sysex data is being received, the display and LED updating will pause. This is normal.

Two MIDI receive channels are now supported - the one you select (A), and the next higher channel (B). If the selected channel is 16, the next higher channel is 1. In split mode, MIDI notes from the A channel are fed to the upper voices and B feeds the lower voices. If not in split mode, notes on the B channel are ignored. When using CC's to change voice parameters, CC's on channel A control upper voice parameters, and channel B controls lower voice parameters, regardless of mode.

A sort of "step sequencer mode" has been added. This setting only affects sequencer
playback. Sequences are recorded normally. In step mode, all time intervals are set
to the same value. Playback rate can still be controlled using the tempo setting. In
"Ex Tempo" mode, each pulse on CLKI will advance to the next note. For the step mode
to work correctly, recorded events must alternate between note on and note off. Play one key at a time, using just one finger, to insure that each key is released before the next one is pressed. The maximum number of notes in a sequence in step mode is ~180 or so. To toggle between "Real time" (normal) mode and "step" mode, press Tape Enable, then use the 1 switch to select the desired mode, then exit Tape Enable mode. The sequencer mode setting is retained when power is off.

The later Kawai SX-240 firmware had a special test mode, which makes performing some of the calibration steps much easier. To access it, hold C, E, and G at the bottom of the keybed when powering up the unit. Then use C to step through the different modes. You can set DAC offset, DAC full scale, and the resonance point of each voice using this firmware.

SX-240 CC information (numbers are decimal, except for offset)
Function CC # Global Parm Range Value Addr Offset
DCO Bender Amt 03 0-99 0-99 08/88
Porta Speed 05 0-99 0-99 09/89
DCO1 Saw On/Off 14 0-99 0,1 3C/BC.4
DCO1 Pulse Wave 15 0-99 0,1,2 3C/BC.7-5
DCO1 PW/PWM 16 0-99 0-99 0C/8C
DCO1 Sub Osc On/Off 17 0-99 0,1 40/C0.1
DCO2 Coarse 18 0-99 0-99 22/A2
DCO2 Fine 19 0-99 0-99 23/A3
Pitch Range 20 0-99 0,1,2 3C/BC.3-1
DCO2 On/Off 21 0-99 0,1 3F/BF.6
Brass On/Off 22 0-99 0,1 40/C0.0
Noise 23 0-99 0-99 0F/8F
VCF EG Amt 24 0-99 0-99 14/94
VCF KCV Amt 25 0-99 0-99 12/92
VCF LFO Amt 26 0-99 0-99 13/93
VCF Bender Amt 27 0-99 0-99 21/A1
VCF EG Attack 28 0-99 0-99 18/98
VCF EG Decay 29 0-99 0-99 19/99
VCF EG Sustain 30 0-99 0-99 1A/9A
VCF EG Release 31 0-99 0-99 1B/9B
VCA EG Amt 32 0-99 0-99 15/95
VCA EG Decay 33 0-99 0-99 1D/9D
VCA EG Sustain 34 0-99 0-99 1E/9E
LFO Speed 35 0-99 0-99 0E/8E
LFO Delay 36 0-99 0-99 0D/8D
LFO Waveform 37 0-99 0,1,2 3F/BF.2-0
LFO Reverse 38 0-99 0,1 3F/BF.3
LFO Trig 39 0-99 0,1 3F/BF.4
LFO On/Off 40 0-99 0,1 3C/BC.0
Auto Bend 41 0-99 0-99 0A/8A
HPF 42 0-99 0-99 17/97
Ensem On/Off 43 0-99 0,1 3F.5
Glissando On/Off (upr) 44 0-99 0,1 3B.6
Damper Pedal -- 64 0-127
Porta On/Off (upr only) -- 65 0-99 0,1 3B.5
VCF Resonance 71 0-99 0-99 11/91
VCA EG Release 72 0-99 0-99 1F/9F
VCA EG Attack 73 0-99 0-99 1C/9C
VCF Cutoff 74 0-99 0-99 10/90
DCO LFO amt 77 0-99 0-99 0B/8B
VCA LFO amt 92 0-99 0-99 16/96

Use selected MIDI channel for Upper notes (all notes in Dual mode) and parms Channel + 1 for lower notes and parms

All parameters need range of 0-99 for MIDI control. Even on/off ones.
On/Off Parms: 0-49 off, 50-127 on
Three-valued parms: 0-33 first value, 34-67 second, 68-127 third
All CC values > 99 are set to 99.
Addr Offset shows locations in SX-240 RAM where this value is stored for upper and lower programs. It is not used for CC control, just shown for completeness.

SX-240 Sysex format:
Patch dump:
F0 Sysex start
40 Kawai mfr ID
7E special byte
06 indicates patch data dump
pp program number (0-2F/47dec)
dl low nibble
dh high nibble
dl low nibble
dh
dl
... 140dec bytes (70 patch bytes)
F7 MIDI EOX byte
Saving patches to MIDI always saves all 48 patches (7008 bytes)

Sequence dump:
F0 Sysex start
40 Kawai mfr ID
7E special byte
07 indicates sequence data dump
pp sequence number (0-7)
dl low nibble
dh high nibble
dl low nibble
dh
dl
... 1024dec bytes (512 sequence bytes)
F7 MIDI EOX byte
Saving sequences to MIDI always saves all 8 sequences, plus the extra data (8726 bytes)

Sequence extra data dump:
F0 Sysex start
40 Kawai mfr ID
7E special byte
08 indicates sequence extra data dump
01 always a 1
dl low nibble
dh high nibble
dl low nibble
dh
dl
... 480dec bytes (240 sequence extra data bytes)
F7 MIDI EOX byte
Patch and sequence loading requires Memory Protect to be Released"