MIDI Setup

ShowRevue takes two things over MIDI:

• MTC (MIDI Timecode) as a timecode source, from a desk, QLab or anything else that sends it.
• MIDI Show Control (MSC) GO from a grandMA2, which lands in the cue list like any other lighting cue.

It doesn't send MSC or MIDI notes back to anything. The only MIDI it sends is MTC from Timecode Output during playback.

How ShowRevue listens

There's no MIDI port to pick. ShowRevue connects to every CoreMIDI source on the Mac when it starts: USB MIDI interfaces, a desk plugged in over USB, network MIDI sessions, and virtual sources from other apps. It also watches for changes, so a device you plug in (or a network session you connect) later is picked up straight away without a restart.

The upshot: if macOS can see a MIDI source, ShowRevue is listening to it. To check what macOS can see, open Audio MIDI Setup (in Applications ▸ Utilities) and choose Window ▸ Show MIDI Studio. ShowRevue's own list is under Preferences ▸ Lighting Consoles ▸ grandMA2 (Connected MIDI Sources).

note

ShowRevue Timecode in a source list is ShowRevue's own virtual MIDI source, which carries Timecode Output during playback. It isn't a desk.

MTC timecode in

MTC works from any source that sends it: a lighting desk, QLab, a DAW or a timecode box with a MIDI out.

1. Connect the source to the Mac (a USB MIDI interface, the desk's own USB MIDI, or a network MIDI session, below).
2. Turn MTC on. Either pick MTC on the Timecode page of Launch New Show, or go to Preferences ▸ Timecode ▸ Input and switch on the MIDI Timecode (MTC) card.
3. Start the timecode at the source. The card reads Receiving with the current value. Until then it says Waiting for MTC quarter frames…

Things to know:

• ShowRevue reads MTC quarter-frame messages, the stream a running source sends. A source that's parked or only sends a locate message shows nothing until it rolls.
• It takes eight quarter frames to make one full timecode value, so the MTC readout moves in steps of two frames. That's how MTC works, not a fault.
• If no quarter frames arrive for a second, ShowRevue treats MTC as stopped.
• MTC sits below LTC, sACN and Art-Net in Source Priority. If one of those is also arriving, it wins and MTC is the standby. See Timecode.
• MTC input needs a Professional licence (it's part of network timecode). MSC cue input from a grandMA2 only needs Base.

QLab timecode over the network

QLab can send LTC and MTC from a Timecode cue, but it can't send sACN or Art-Net timecode. If QLab is on a different Mac and you don't want to run an audio cable, the network route is MTC over Apple's network MIDI (RTP-MIDI).

1. Set up the network MIDI session on both Macs

On both the QLab Mac and the ShowRevue Mac:

1. Open Audio MIDI Setup, then Window ▸ Show MIDI Studio.
2. Double-click Network.
3. Under My Sessions, click + to add a session and tick Enabled.

Then on the QLab Mac only:

4. In Directory, select the ShowRevue Mac and click Connect. It appears under Participants.

On the ShowRevue Mac the session now shows up as a MIDI source, and ShowRevue starts listening to it on its own.

2. Send MTC from QLab

In QLab 5:

1. In Workspace Settings ▸ MIDI, set one of the MIDI patches to the network session.
2. Add a Timecode cue. On its Settings tab, set Type to MTC, choose that MIDI Patch, and set the Framerate and start time to match the show.
3. Run the cue.

Timecode cues need a QLab licence (any kind). QLab's own docs cover the cue in more detail: Timecode Cues.

3. Pick MTC in ShowRevue

Choose MTC as the timecode source (in Launch New Show, or the MIDI Timecode (MTC) card in Preferences ▸ Timecode). With the QLab cue running, the card reads Receiving.

Caveats

• Network MIDI jitters. Timing over a network isn't steady, and QLab's own documentation warns against sending MTC this way for the same reason. Use wired Ethernet between the two Macs, not wi-fi, and check the readout runs smoothly before you rely on it.
• Every MTC source is merged. ShowRevue listens to all MIDI sources at once and doesn't keep their MTC apart. If two things send MTC at the same time (QLab and a desk, or two QLab cues), the readout jumps about or goes bad. Run one MTC stream at a time, and keep ShowRevue's own MTC output off while you're relying on MTC in.

Alternatives

• LTC from QLab to an audio input. Set the Timecode cue's type to LTC, send it to a spare audio output, and patch that into an input on the ShowRevue Mac. Pick LTC as the source. This is the steadiest option.
• LTC over Dante. If both Macs are on Dante (Dante Virtual Soundcard or an interface), send the LTC output over the network as audio and pick that Dante channel as the LTC input in ShowRevue.

grandMA2 cue input (MIDI Show Control)

A grandMA2 sends a MIDI Show Control GO each time a cue runs. ShowRevue records each one as a lighting cue. It's receive only: ShowRevue can't fire cues back to an MA2.

On the grandMA2

These settings are in the MA2's MIDI Show Control menu (press Setup, then MIDI Show Control under the Console tab, per the grandMA2 manual). Set the out row:

Setting	Use
Mode	MIDI. ShowRevue listens on MIDI ports, not MSC over Ethernet.
Exec	Default Only is simplest. ShowRevue reads the cue number whatever this is set to.
Command (format)	Any. General Light, Moving Light and All all work.
Device / Send to	Any. ShowRevue accepts any MSC device ID, including All (broadcast).

The MIDI channel doesn't matter, because MSC is SysEx and doesn't use one. Then connect the MA2's MIDI out to a MIDI interface on the Mac.

note

If the menu isn't where you expect on your software version, look for MIDI Show Control in Setup.

In Launch New Show

Pick grandMA2 on the lighting console page. Its setup page lists the MIDI sources the Mac can see. There's nothing to choose, because ShowRevue listens on every one. Press GO on the MA2 and the Cue received from the desk check ticks with the page and cue number it got. There's no fire-back test, because ShowRevue doesn't send to an MA2.

In Preferences

Preferences ▸ Lighting Consoles ▸ grandMA2 shows:

• MIDI listening (or No MIDI sources), how many sources are connected, and Last cue, the time since the last GO arrived.
• Connected MIDI Sources, the list ShowRevue is listening to.
• How to connect GrandMA2 and an MSC Protocol Reference.

Only the MSC GO command is read. Other MSC commands, and MIDI notes, are ignored.

See also grandMA2.

Choosing a MIDI interface

MSC travels as SysEx, and that's where cheap interfaces fall over. Unbranded USB-MIDI cables (the sort sold as "Funs-tech" and similar) often pass notes fine but drop or corrupt SysEx, so an MA2's GOs go missing. They can also mangle MTC timing.

Use a class-compliant interface from a known maker. The Roland UM-ONE mk2 is a good, inexpensive choice that handles SysEx properly. It needs no driver on a Mac.

To check an interface before the show, there's a free MIDI test app at showrevue.com/tools/miditest (a Mac download). Run it, send from the desk, and see whether every message arrives intact.

Troubleshooting

No cues arriving from the MA2

• Check the source is in Connected MIDI Sources. If it isn't, macOS can't see the interface: look in Audio MIDI Setup, try another USB port, or replug it (ShowRevue picks it up without a restart).
• Check the MA2's MSC out Mode is MIDI, not Disabled or Ethernet.
• Watch Last cue in Preferences as you press GO. If notes get through but GOs don't, suspect the interface dropping SysEx and try a better one.
• Cues only go into the cue list while you're recording. The wizard check and Last cue work any time.

MTC not arriving

• Make sure the MIDI Timecode (MTC) card is switched on, and that the source is actually rolling.
• Over network MIDI, check the session is Enabled on both Macs and the QLab Mac shows the ShowRevue Mac under Participants. Check QLab's MIDI patch points at the session.

Readout jumps or looks wrong

• More than one thing is sending MTC. Stop all but one.
• On network MIDI, move to wired Ethernet, or switch to LTC.

Wrong frame rate

• ShowRevue records the frame numbers it receives. Set the frame rate at the source (the QLab Timecode cue's Framerate, or the desk) to the show's rate, and match it on every other device chasing the same timecode.

The timecode pill

• Green (LTC LOCKED): timecode is arriving from the winning source.
• Gold (LTC WEAK): an LTC signal is there but not clean. Check the level on the LTC input.
• Red (NO LTC): nothing is getting through.

When MTC is the source that's winning, check the MIDI Timecode (MTC) card in Preferences ▸ Timecode as well. It shows whether MTC is being received and the current value.