MIDI Configuration
Gravitas allows all of its parameters to be controlled via control change messages, it's presets to be saved and
recalled with program change messages, and its tempo controlled with MIDI clock messages.
To use MIDI with your Gravitas , you'll have to do the following:
1)
Attach a Chase Bliss Audio Modified Empress Midibox “Ring Active” port using a standard ¼” TRS patch
cable to the TAP/MIDI jack on your Gravitas. The Midibox is not included with the Gravitas . If you do not
have a modified Empress Midibox, but a standard one from Empress, you need to use a custom TRS cable
that flips the tip and the ring. See
www.chaseblissaudio.com
to purchase these items.
2)
Gravitas is set to MIDI channel 4 by default, but it is easy to change if you need to. If you want to change it,
simply hold down both stomp switches when you provide power to the pedal (hold down TAP and BYPASS
switches simultaneously) and then you can let go. The pedal is now looking for the first “Program Change”
message it sees, and it will set itself to whatever channel it gets that first message from, permanently (until
you change it again, of course).
Recalling a preset via MIDI
You can activate a preset by sending a MIDI Program Change message. For example, sending a Program Change
message of 1 activates preset 1. There are 122 total preset slots available. Slots 1 and 2 are the presets that can be
saved and activated directly from the pedal via the preset toggle. Slot 1 is the right slot, Slot 2 is the left slot.
Sending a Program Change message of 0 puts the pedal in “Live” mode which is identical to when the preset toggle
switch is in the middle position, in normal pedal operation. If you do not save something into presets 3 through
122, nothing will be recalled. There are no factory presets besides the two that come loaded in slots 1 and 2. The
idea is for you to create your own.
Saving a preset via MIDI
You save a preset by sending a MIDI Program Change message while holding down both the TAP and BYPASS
stomp switches. For example, sending a Program Change message of 45 while holding down both the TAP and
BYPASS stomp switches will save your current settings to preset 45. There are 122 total slots. Slots 1 and 2 are
the presets that can be saved and activated directly from the pedal via the preset toggle. Slot 1 is the right slot, Slot
2 is the left slot.
MIDI Clock (aka MIDI Beat Clock)
The Empress Tremolo2 will respond to MIDI Clock messages. MIDI Clock specifies quarter notes, subdivided into
24 MIDI Messages. By using the tap selection toggle, you can select different types of notes so that they correspond
to 1 period of tremolo’s waveform. On the tap division toggle first bank: 1 = whole note, 2 = half note, 4 = quarter.
On the tap division toggle second bank: 3 = dotted eighth, 6 = eighth, and 8 = sixteenth note. I chose these notes as
I thought they would be the most useful.
