Here is what should work with 2 H9s (only). (This have been tested and done by many)
Both H9: Global tempo set to “NO”
First H9: (master)
– Midi output mode: “transmit”
– Enable Midi input clock: “NO”
– Enable Midi input Filter: “NO” (could also be set to yes as it is irrevelant)
– Enable Midi output clock: “YES”Show More...
Second H9: (slave)
– Midi output mode: “thru”
– Enable Midi input clock: “YES”
– Enable Midi input Filter: “NO” (could also be set to yes)
– Enable Midi output clock: “NO”
With this setup tapping a tempo on the first H9 will make it to send the midi clock to the second H9, which will adjust the tempo accordingly.
Note that the tap tempo is sent to the second H9 as a midi clock. (The “tap” itself is NOT sent)
Adding a 3rd H9 with the same setting as the 2nd one will also work.
But then this is not what you want to do when you will add the GCP in front of that… You have to understand that the GCP can’t send midi clock, it can just be configured to send a midi CC that could then be used by the H9s as a tap tempo. In this case all three H9s will be set the same way and none of them will send or receive a midi clock. They will all three internally generate the tempo from the received midi CC from the GCP. This have also been done by many and I (and others) could help if you run into troubles with that.