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Mobile Rig Archival Recording Guide

21 Apr 2017

General Information

  • The mobile rig is equipped with a rack mounted Tascam CD player / SD Recorder for the purpose of both playing back audio from CDs and creating archival recordings of each and every show.
  • The Tascam unit has two balanced analog audio inputs, typically used for a stereo input recording. In order for us to be able to record everything coming out of the mixer, as well as an ambient mic to pick up the room, we have repurposed these two inputs so that the left channel takes everything coming out of the board, and the right input takes audio from an area mic which will be set up and plugged into the AREA MIC input on the back of the rig (more details below). The Tascam then takes these inputs and sums them into a single mono audio file.

If you are in the Penthouse:

  1. Skip steps 3 and 4 below, you will use one of the hanging house mics in the space instead. To do this go into the 901 patchbay and patch CEILING MIC 3 to TIE LINE 3. If you need only room mics for your recording, you can use both of ceiling mics 3 and 4 to tie lines 3 and 4. Pick up that tie line at the AVP (near the lighting board) and patch it into the area mic input of the I/O panel on the back of the mobile rig. You will not need 48+ Volts.
    Proceed from step 6 below.

How to set up a proper recording

  1. Make sure you have correctly set up the mobile rig and turned it on.
  2. The audio being sent out of your mixer will automatically be sent to the left input channel on the Tascam as long as you have your Mono master fader (the black master fader) turned up to 0db.
  3. Get a microphone, mic clip and stand from mic storage. The microphone would preferably be a small diaphragm condenser microphone (colloquially known as pencil mic) like our KSM 137s. If both of these are unavailable, then grab one of our SM27s (our large diaphragm condenser mics). If these are unavailable, then just grab an SM57 or in last case scenario an SM58.
  4. Place the mic stand and microphone somewhere in the house, preferably some place you will receive a robust ambient signal from both the stage and house without picking up too much chatter from the technical crew. Point the mic at the stage and cable it back to your mobile rig without creating a trip hazard for anyone.
  5. Plug into the AREA MIC input in the I/O panel on the back of the rig.
  6. There is a single channel Behringer mic-pre on top of the Tascam unit. Your area mic goes through this and into the Right input channel of the Tascam. From the front of the rig you can control the gain and other parameters (+48 volts, limiter…) for your area mic. If you grabbed a condenser then you will need to give it 48+ volts, and make sure the limiter button is pressed down (regardless of the type of mic).
  7. On the Tascam unit, press MENU (button) -> UTILITY -> MEMORY FORMAT -> YES (enter) before every show in order to empty the SD card and ensure enough free space for your entire show.
  8. Hit the record button on the Tascam to put it into standby mode and activate metering. During sound check, adjust the gain knobs while looking at the metering on the Tascam digital display. Optimally you want to plug your headphones into the PHONES input on the front right of the Tascam and adjust levels until you are getting a nice mix between the output of your board and the area mic. If you can’t do this, just make sure neither one of the input signals is clipping or alternatively not showing any signal. When mixing these channels, consider the type of program when determining the levels of these two channels (more close mics for lectures and panel discussions, more area mics for jazz shows or mostly unamplified events). Check your mix often.
  9. When the show starts, hit the record button on the Tascam and then hit the play button next to it to start recording. Again, make sure you are getting signal by looking at the meter on the digital display.
  10. When the show ends, hit the stop button, eject the SD card, plug it into a computer, and send the file to erinbrenner@uchicago.edu via WeTransfer.com.

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