HX3 mk3/mk4 additional info

HX3 mk3 jumper wires (supplied with HX3 mk3 board) configuring left MIDI DIN jack as standard MIDI OUT. For HX3 mk4 series, use plain jumpers (see text at bottom).

HX3 mk3 jumper wires configuring left MIDI DIN jack as secondary MIDI IN (wires may be replaced by jumper bridges). Jumpers for phantom supply of secondary MIDI input are not installed here.

FTDI Cable connected to HX3 board. Your board may be equipped with a non-angled or white pin header; just regard wire colours.

New HX3 mk3/mk4 boards are equipped with stereo Leslie® simulation, secondary MIDI input and configurable mono audio output jacks.

On factory default for HX3 mk3/mk4, menu item "Jack Config A" yields bass pedal on left (inner) audio jack, plain organ signal (like G-G on B3 AO28) on right (outer) audio jack. "Jack Config B" yields stereo Leslie® simulation on both jacks with added dry bass pedal signal. Both configurations may be changed to any combination with "AudioJ Conf A" and "AudioJ Conf B" menus (scroll down to access).

Jumpers JP5 und JP7/8 (I2C_REV) must be removed during operation - only needed for factory programming. JP6 must be set to REF position (not on HX3 Expander).

HX3 mk3/mk4 has an auxiliary connector PL8 behind the audio jacks which carries auido signal as present on jacks. Similar, two connectors PL18 and PL19 are swell (SWL) and footswitch inputs (connected to control jacks) for internal use.

PL16 (not installed) might be used for future use.

HX3 mk3/mk4 Tab/Switch Connection

HX3 mk3/mk4 does not have additional tab switch inputs PL8/PL12 with same functiononality as button/LED inputs PL7/PL11. Instead, button/LED toggle pins on PL7/PL11 may be configured individually as switch inputs by HX3 Remote software, Organ Defaults parameters 478 and 479. A checked box indicates a switch input, an unchecked box means a toogling button/LED input. Default is toggle inputs for Panel16 or button connection.

For other connectors, see page HX3 Board Installation.

HX3 mk3 boards have a spare footprint U12 for an additional PCA9554AD I2C port circuit which may be used to control external preamplifiers etc. If populated (standard on mk4), PL17 carries following signals (active high) with firmware #3.6 and up:

PREAMP_DBSELECT_UPPER Pin 1, Drawbar A/B Select for Upper Preset 1/15
PREAMP_DBSELECT_LOWER Pin 2, Drawbar A/B Select for Lower Preset 1/15
PREAMP_LESLIE_RUN Pin 3
PREAMP_LESLIE_FAST Pin 4
PREAMP_REV1 Pin 5, Reverb I
PREAMP_REV2 Pin 6, Reverb II
PREAMP_OD1 Pin 7 (not used)
PREAMP_OD2 Pin 8 (not used)

HX3 mk3 Secondary MIDI Input

Both MIDI DIN jacks are wired by internal jumpers as MIDI inputs with merge as pictured. Please disregard lettering on old HX3 MIDI expander back panel. You may use a MIDI master keyboard and a additional MIDI keyboard or MIDI drawbar controller. Original MIDI OUT configuration may be obtained by internal jumper setting. Also, MIDI phantom supply may be routed to left MIDI input by placing two additional jumpers.

Phantom supply on secondary MIDI IN may be enabled by placing one jumper to two rightmost pins of PL6 and one jumper on JP13. When phantom supply jumpers are installed, DIN jack carries ground on middle pin and +5V on two otherwise unused outer pins.

Factory default for "MIDI Custom CC" set is Nord C2 organ (works also with Ocean Beach DB-1 drawbar controller); all MIDI controller assignments may be changed by HX3 Remote application (USB adaptor cable required) to any desired value.

HX3 mk3/mk4 Firmware Update

On HX3 mk3, no additional jumpers must be installed for updating with HX3 Remote application. Please use HX3 Remote application contained in firmware update ZIP or HX3 Flash packages provided in Github Repo.

HX3 MIDI Expander: To access internal configuration port with FTDI USB adaptor cable, please unscrew front panel and remove top lid. MenuPanel should be left connected to view messages on display. Models with USB port use simple Mini-USB cable instead, no FTDI cable needed.

HX3 mk4 Changes

Inconvenience of jumper cables for MIDI in/out configuration was due to design quirk on HX3 mk3 boards and has been corrected on mk4 series. HX3 mk4 also has a "preamp control" output with rotary, reverb and drawbar A/B switch control signals on PL17 (see avbove). Summary:

• Preamp control circuit U12 is alsways populated to use PL17
• MIDI configuration connector PL6 has been renamed to PL10. You may connect switches to configurate MIDI IN/OUT or use jumpers (see below).
• Jumper setting for left MIDI OUT is 1-2, 4-5 and 7-8 on PL10 (3 jumpers, leftmost pin is 1)
• Jumper setting for left MIDI IN is 2-3 and 6-7 on PL10 (2 jumpers, leftmost pin is 1)
• For +5V phantom supply on MIDI IN set additional jumper on pins 7-8 and 9-10. When phantom supply jumpers are installed, DIN jack carries ground on middle pin and +5V on two otherwise unused outer pins.
• Jumper setting for left MIDI IN is 2-3 and 5-6 on PL10 (2 jumpers, similar second pic)
• PL14 has internal pullups so using FatarScan core with no scan board attached will produce noise.

HX3 mk4 MIDI Hardware Configuration

From factory, both MIDI DIN jacks are wired by internal jumpers as MIDI inputs with merge by two jumpers on PL10, bridging pins 2-3 and 5-6. The left MIDI jack may be configured as a MIDI output by placing jumpers on PL10 pin 1-2 and 3-4 instead of 2-3 and 5-6. Place an additional jumper on pins 7-8 for ground on MIDI output. Seen from back, PL10 pin 1 ist the leftmost pin.

A +5V MIDI phantom supply on outer pins of MIDI input for MIDISCAN25 bass pedal board may be obtained by two additional jumpers on HX3 PL10 pins 7-8 and 9-10. Do not install these jumpers if connecting other MIDI gear not using a phantom supply.

If the Extension board is installed, both MIDI jacks on mainboard should be jumpered as MIDI INs as the Extension board has its own MIDI OUT.