If in doubt, ask.

User Manual

Please refer to the image below:



House the FHX-1 in a Eurorack case of your choosing. The power connector is Doepfer standard. If using the power cable supplied with the FHX-1, the connector is keyed and will only insert into the FHX-1 the correct way round, in which case the red edge of the cable is nearest the edge of the PCB, and carries -12V. ("-12V" is marked on the PCB itself next to this end of the connector.) Be sure to connect the other end of the power cable correctly, again so -12V corresponds to the red stripe on the cable.

The FHX-1 also needs to be connected to an FH-1 module via its "Expansion IN" connector. A 10-way cable is supplied with the FHX-1. With this cable fitted as shown above, the red stripe should be oriented at the other end in the same way i.e. with the red stripe closest to the power connector.

Note: while the 10-way connector on the FHX-1 may look like the power connector on some Doepfer modules, it is not wired the same. If you connect this to a Doepfer power bus, you will almost certainly fuse the power supply and fry the FHX-1. This connector is only to be used for connecting the FHX-1 to an FH-1.

When multiple FHX-1s are to be driven from a single FH-1, they are daisy-chained. The first connection is from the FH-1 to the first FHX-1's Expansion IN connector. The second connection is from the first FHX-1's Expansion OUT connector to the second FHX-1's Expansion IN connector. Further FHX-1s are connected in the same manner. All the expansion cables are oriented the same way - if you find yourself twisting the cables, chances are you're inserting the ends incorrectly. With a row of FH-1/FHX-1s, all the cables should stay flat.

Note that each FHX-1 requires its own individual power connector as well as the expansion connector.


There are 11 possible jumper positions on the FHX-1's PCB.

Output level jumpers

The 8 jumpers numbered JP1-8, situated in a row above the jack sockets, set the voltage range for each output. The options are:
  • ±5V - jumper in lower position (factory default setting)
  • 0-10V - jumper in upper position
  • 0-5V - jumper not fitted

Expander selection jumpers

Next to the Expansion IN connector are two 3-way jumper blocks numbered JP9 & JP10. These are used to select which of the possible 8 expansion channels this FHX-1 responds to.

Channel 'zero' is the FH-1 itself. Channels 1-7 are the expansions channels, corresponding to outputs 9-64.

The expansion channel is selected by placing jumper links in a binary pattern between JP9 and JP10. As shipped (and as in the photo above), a jumper is placed in position '3', which corresponds to a value of 1, so the FHX-1 responds on expansion channel 1.

The position labelled '2' corresponds to a value of 2, and the position labelled '1' corresponds to a value of 4. Therefore, the 7 expansion channels are selected by placing jumpers as in the table below: