HX3 MIDI expander module

HX3 MIDI expander is a tonewheel organ in a small box! Controlled completely via MIDI, selectable CC-sets for NI B4, Hammond XK, Hamichord and other. 30 presets (to be stored locally), many "secret" HX3 parameters tweakable by menu with incremental encoder - like key contact flex and damping for key click response, or AO28 gain adjustments for more or less percussion punch etc. And, of course, it yields the legendary unmatched HX3 sound.

Kit Assembly

You will need only a phillips screwdriver to build! The HX3 expander kit comes with fully functional boards, front and rear bezel/panel, cables, screws and aluminum enclosure. Make shure you have a size 1 PH screwdriver handy, also small pliers or metric 5.5 mm wrench to holt the nuts while fastening.

• Install HX3 main board to rear panel. The 4 jack nuts hold the eintire board. The 4 washers are to be installed outside of rear bezel.
• Use M3 screw, locking washer and M3 nut to fasten the voltage regulator to back panel. The voltage regulator's body should have full contact to back panel as it is used as a heat sink.
• Fasten MenuDisplay board to front panel using 6 M3 bolts with spacers. Space between board and front panel should be approx. 12 mm. Be shure not to bend LED wires.
• Fasten side panels to front panel using 4 self-tapping screws.
• Insert bottom panel into slots of side panel.
• Connect 2 flat-ribbon cables to board connectors as pictured.
• Set jumper JP6 on HX3 main board to appropriate operation: In position "MONO", organ main and pedal outputs are mixed to one channel on MIN/BASS output jack, in other position to separate channels (pedals on plug "ring", right channel).
• Be shure to remove jumper JP12 (near DC jack) if using a 9 to 12V DC power supply (default: no jumper). If you plan to use a 5V power supply, move jumper from AGND spare position to JP12. Note: Damage will occur if higher voltage than 5V applied whith JP12 installed!
• Fasten side panels to back panel using 4 self-tapping screws.
• Affix 4 self-adhesive bases to bottom panel in each corner.

You're done! Time to try out: Plug in appropriate power supply 9 to 12V 800mA min. to DC jack. Display will illuminate and show welcome message, serial number and owner information (your name per default). Turn knob to select a preset. LEDs on right side will show corrsponding vibrato/percussion setting.

Using the Menu System

HX3 expander may be remoted via given MIDI CC set, but some settings are available via menu system only.

• Use the incremental encoder button "DATA ENTRY" to change parameters or presets in main UPR/LWR menu.
• Press incremental encoder button to go back to last menu intem used (Leslie Amp Volume by power-on default).
• Use Up/Down buttons to scroll through menu items.
• Press incremental encoder button for 2 seconds ore more to save a changed parameter (also by MIDI CC) or preset permanently (non-volatile).

The menu system consists of about 60 entries. Pressing and holding the Up/Down buttons will enable fast auto-repeat which will stop shortly on menu group borders. A "<" mark will direct to the parameter to be changed.

Main Group Upper

These parameters are saved to upper manual preset when encoder knob is pressed more than 2 seconds.

• UpperDB 1 to UpperDB 16 - drawbar setting for upper manual
• UPR<LWR Vibr - vibrato/chorus ON/OFF for upper manual
• UPR LWR Vibr< - vibrato knob setting V1 to C3
• Percussion - will step through available percussion options
• UPR XXXXXXXXX - default main menu, shows upper drawbars, incremental knob changes preset nummer upper

Main Group Lower

These parameters are saved to lower manual preset when encoder knob is pressed more than 2 seconds.

• LWR XXXXXXXXX - shows lower drawbars, incremental knob changes preset nummer lower
• UPR LWR<Vibr - vibrato/chorus ON/OFF for lower manual
• LowerDB 16 to LowerDB 1 - drawbar setting for upper manual
• PedalDB 16 to PedalDB 8 - drawbar setting for pedals
• PedalSustain - changes pedal sustain release time. Set to 0 to obtain B3 pedal sound. Saved to lower preset
• BassOnLeslie - routes pedal signal to Leslie simulation if ON
• KeyboardSplit - set split ON or OFF, default pedal to lower, 2 octaves. If one key pressed while switching to ON on lower manual, this key will be the "pedal to lower" split point. If one key pressed while switching to ON on upper manual, this key will be the "lower to upper" split point, lower manual switched off. If two adjacent keys pressed while switching to ON on upper manual, this key will be the "pedal to upper" split point. Note: split point setting is only valid until power-off.
• LeslieVolume - adjusts Leslie Amp simulation volume from 0 to full (overdriven tube amp).
• ReverbLevel - adjusts reverb level OFF, 1, 2 or 3.

Main Group Defaults

These parameters are saved to power-on defaults when encoder knob is pressed more than 2 seconds.

• MIDI Channel - sets MIDI base receive channel 1 to 10 (upper manual, lower manual is on +1, padels on +2).
• MIDI Option - sets MIDI routing behaviour to 'ReceiveThru' (MIDI OUT is THRU), 'ReceiveSend' (MIDI received, only own MIDI key events to MIDI OUT), 'RcvSendMerge'(MIDI received, own MIDI key events and incoming MIDI events merged to MIDI OUT) and 'RcvSndMgNoCC' (as before, but MIDI CC commands discarded). On expander module, only valid setting is 'ReceiveThru'.
• MIDI CC Set - sets recognized MIDI CC set to 'NI B4' (default), 'Voce', 'Hamichord', 'Hammond XK', 'Hammond SK' or 'KeyB Duo'. Note: Hammond changed MIDI CC set between XK and SK series, so try out which will fit.
• SplitOption - split setting on power-up, 'PedalToLower', 'LowerToUpper' or 'PedalToUpper', engaged when split set to ON (see above).
• Transpose - transposes from -6 to +7 semitones. Notes beyond 5 octave limits of B3 will not produce any sound due to accuracy of physical model.
• Vib1 AmplMod - adjusts amplitude modulation caused by delay line on V1/C1 knob setting.
• Vib2 AmplMod - adjusts amplitude modulation caused by delay line on V2/C2 knob setting.
• Vib3 AmplMod - adjusts amplitude modulation caused by delay line on V3/C3 knob setting.
• Vib1 FreqMod - adjusts frequency modulation on V1/C1 knob setting.
• Vib2 FreqMod - adjusts frequency modulation on V2/C2 knob setting.
• Vib3 FreqMod - adjusts frequency modulation on V3/C3 knob setting.
• ChorDryMix - adjusts vibrato chorus mix dry (unmodulated) part in C1/C2/C3 setting.
• ChorVibMix - adjusts vibrato chorus mix wet (FM/AM modulated) part in C1/C2/C3 setting.
• PercNormLvl - adjusts percussion level in PERC ON, NORMAL tab setting.
• PercSoftLvl - adjusts percussion level in PERC ON, SOFT tab setting.
• PercLongTm - adjusts percussion length in PERC ON, SLOW tab setting (higher value = faster).
• PercShortTm - adjusts percussion length in PERC ON, FAST tab setting (higher value = faster).
• TG Flutter - adjusts tone generator "sloppyness" (spring clutch tension, bearing precision).
• TG Leakage - adjusts tone generator leakage to 'OFF', 'New Organ', 'Old Organ' or 'Sleazy Organ'.
• TG OldCaps - sets generator red caps (OFF) or wax caps (ON).
• No DB1 @Perc - disables drawbar 1 cancel when percussion ON.
• No DB16 Foldb - disables foldback on lowest octave ("all way down" when ON).
• TrebleEqu - mimics TONE pot on AO28 amp.
• BassEqu - bass equalizer, adjusts bass response of different AO28 models (rather subtle).
• ContSpringFlx - adjusts key contact spring flex, affects click length
• ContSpringDmp - adjusts key contact spring damping, affects click frequency
• HornSlowTm - Leslie simulation horn revolution timer when set to SLOW
• RotorSlowTm - Leslie simulation rotor revolution timer when set to SLOW
• HornFastTm - Leslie simulation horn revolution timer when set to FAST
• RotorFastTm - Leslie simulation rotor revolution timer when set to FAST
• ScanBoard - sets scan core for attached scan board (MIDI only on expander)
• ExpanderMode - disables all analog control pot/drawbar inputs despite swell pedal (ON default on expander)
• SwellInEna - enables swell pedal input jack, default ON
• FixedSwell - fixed swell volume if swell pedal disabled
• TonePotEna - enables analog control input for TONE pot (OFF on expander)
• LesVolPotEna - enables analog control input for 122 Amp simulation volume pot (OFF on expander)