A number of years ago, Avid released the PRE, an 8 channel microphone preamp designed to work either as a standalone unit or to integrate with a Pro Tools HD system. In terms of sound, it has sometimes been described as boring or clinical. It does, however, offer a low noise floor and minimal colouration. One area in which it really comes into its own though is in its ability to be remotely controlled over MIDI from Pro Tools. In fact, the PRE protocol has been implemented by a number of third party microphone preamp manufacturers. More on this later.
PRE receives its remote control commands via a standard MIDI connection. In order to accommodate this, you will need a suitable MIDI interface. A connection from the MIDI Out port on the PRE will need to run to an available MIDI In port on your MIDI interface. Another MIDI cable will make the connection between the MIDI In on the PRE and the MIDI Out on the MIDI interface. Up to 9 Avid PRE’s can be used in a single Pro Tools HD setup. If you’re controlling more than one PRE from a single MIDI port, each PRE will need to be assigned a unique MIDI channel number. To do this, press the MIDI Chan switch on the front of the PRE turn the Gain/Param control to select the desired MIDI channel for that unit. Assign each unit its own channel number.
The Avid PRE outputs line level audio on a DB-25 connector. With an appropriate cable for your audio interface, connect this straight into 8 line inputs. If you’re using an HD I/O with analog inputs, the connection is made with a single DB-25 cable. Some older interfaces, such as the 96 I/O will require a DB-25 to TRS cable.
Configuring MIDI in AMS or MSS
This next step will be slightly different depending on whether you’re using a mac or a PC. From Pro Tools, choose Setup > MIDI > MIDI Studio.
On mac systems, Audio MIDI Setup will launch or on PC, MIDI Studio Setup. If you’re on a mac, make sure the MIDI Studio window is visible. Next, add a new device and choose Digidesign for the manufacturer (yes, it’s still listed as Digidesign!) and choose PRE for the Model.
Assuming that your MIDI interface is already connected properly, you should see it represented in the MIDI Studio window. On the mac, draw cable connections between your MIDI interface and PRE to represent the physical connections.
If you're working on a PC, select the port to which the PRE is connected and choose the send and receive channels. When using multiple PREs, this will of course reflect the MIDI channel number you selected from the front port of each unit.
In part 2 of the article, I'll be describing how to configure PRE in Pro Tools, how to assign its outputs to your audio interface and some of the third party remote controllable preamps which support the PRE protocol.