Assignment 1

Assignment 1: Recording

In this assignment, you’ll learn how to make high-quality recordings of sounds that you can use in the next two assignments.

You will record several sounds that are not explicitly musical, focusing on making clear recordings with no distortion and low noise.

Goals

  • Get practice setting up a condenser microphone on a boom stand.
  • Understand the studio’s 16-channel 4-bus analog mixer and how sound signals may be routed through the mixer to the computer.
  • Optimize gain: control volume along the signal path.
  • Learn how to record into the ocenaudio program.
  • Record several types of sound for use in your music.

Choosing Sounds

Bring to the studio objects whose sounds you would like to record. Since we’re recording sounds that are not explicitly musical, avoid making sounds on musical instruments or electronic devices that play music (or are used when making music).

The idea is to record individual sounds — sound objects — rather than a musical performance having prolonged rhythmic and/or melodic features.

Make the following four types of sound with whatever you bring to the studio:

  1. a percussive attack, with or without ringoff;
  2. a sustained noisy sound (can be bumpy and irregular, but should be fairly continuous), with no discernable pitch;
  3. a sustained sound having some pitch, such as you might hear rubbing a wine glass or a prayer bowl; and
  4. a passage of you reading (or whispering) the newspaper (or similar) in any language (can be an excerpt from a poem or novel, as long as it’s in the public domain or you otherwise have permission to use it in your own music).

NOTE: When you record source material, get in the habit of making a series of versions — performances, if you will — that vary subtly, with each version separated from the next by a second or two of silence.

Each recording should be 15-30 seconds long, containing several versions of one sound source.

CAUTION: Please don’t bring fire into the studio (e.g., matches, lighters), even if cool sounds might’ve emerged. Be very careful with water and other stuff that could make a big mess. Use common sense.

Process

There are several steps involved in making a good recording in our studio.

  • Set up one AKG C414 microphone, and connect it to the mixer.
  • Set the mixer controls so that you get an optimum sound level from the mic — not too soft, not too loud — coming into the mixer.
  • Set the mixer controls to route the microphone signal into the computer for recording.
  • Prepare for recording in Adobe Audition, and adjust sound level coming into the program.
  • Record and save your sound.
  • Listen critically to your sound, and repeat the process as needed.

The more recordings you make, the better you will get at this process.

Details

Here are detailed steps you should take to do the assignment.

Preparation

  1. Look at the Furman power conditioner in the rack. If there’s a light blinking above “Delay 1,” then you will need to turn the studio power on by pressing the gray button on the power conditioner. The equipment will come on in a preset sequence, with delays. Note that the computer is the exception: its power should stay on. If it’s off for some reason, power it on manually by pressing the power button, which is on the back of the computer, at the lower left side.
  2. Zero out the mixer, if it hasn’t already been done: working up from the bottom of the mixer, pull all the faders down; leave the pan knobs set as they are (odd channels panned hard left, even channels panned hard right); set all EQ to center detents; set all Aux knobs to their leftmost position; set all Gain (i.e., trim) knobs to their leftmost position. Make sure all buttons are up.

Setting up the Microphone

  1. Set up one AKG C414 microphone on the mono mic stand:
    • The mics and cables are in the top drawer of the left filing cabinet that’s under the desk next to the door. Place the mic stand close enough to the mixer so that you can operate the mixer controls while speaking or otherwise making noise into the mic.
    • Plug the male end of the cable into input channel 1 on the mixer. The XLR jacks are on the top of the mixer.
    • Unscrew the set screws of the microphone shockmount a few turns so as to leave enough room to insert the microphone barrel. Bring the female XLR end of the mic cable up through the shockmount and, while holding the mic above the shockmount, plug the mic cable into the bottom of the mic.

      Just a reminder: the silver screen is the front of the mic, and is the part you would talk or sing into; the black screen is the back.

    • Now lower the mic into the shockmount. Tighten the set screws so that the shockmount holds the mic securely.

    • Turn on the mixer’s phantom power switch. (It’s next to the mixer’s power switch. Press the bottom part of the rocker switch to turn it on — to the position marked with a dash.)
    • When you are recording vocal sounds, including speech, you should use a pop filter to prevent plosives and breath from moving the microphone diaphram around too much. Normally, you don’t use the pop filter when not recording vocals.
  2. Set the microphone switches appropriately.
    • Pattern — choose between cardioid, hyper-cardioid, omni, and figure-eight. Usually, you’ll want cardioid.
    • Pad — set to 0 dB for speech and softer instruments, -10 or -20 dB for trumpet, percussion, screaming, etc. Without doing this, you might make a recording that sounds distorted, even though the meters on the mixer and computer do not show clipping.
    • Bass roll-off switch — Set to 70 Hz or 100 Hz to reduce mic stand vibrations, popping from voice, etc. The only time you will turn this off is if you’re recording low sounds: anything that has a pitch below the G string on the cello (c. 100 Hz).

Setting up the Mixer

  1. Set the mixer controls so that you get an optimum sound level coming into the mixer.
    • Set the microphone channel fader to unity (0 dB).
    • Speak or play an instrument (whatever it is you want to record) into the mic.
    • Adjust the GAIN control so that you see a little flickering on the green light above the channel fader, but you never see a red light. For speech, the GAIN knob will probably be at about 2 o’clock; for trumpet, maybe 12 o’clock.

      NOTE: Turning the gain knob all the way up to amplify soft sounds is counterproductive, because the top range of the mixer’s mic preamp is noisy. Better to keep it < 4 o’clock, and be sure to record in 24-bit resolution.

  2. Set the mixer controls so that the mic signal is routed into the computer for recording.
    • On input channel 1, where you connected the mic, keep the fader at unity gain, and engage (i.e., press down) the 1-2 button. This routes that input channel to the 1-2 sub outs (or group outs) in the mixer’s output section. You will notice that those are labled MOTU IN 1-2. This means that the sound goes to those input channels on the MOTU Ultralite AVB audio interface in the rack.
    • Note that the pan knob on input channel 1 should be all the way to the left.
    • In the output section, raise the sub out 1 fader to unity gain.
    • In the SOURCE section, engage the 1-2 button. This meters the signal arriving at the 1-2 sub outs. (To listen to the sound with headphones, raise the CTLROOM/PHONES knob.)
    • Make sure the L/R fader at the far right, controlling the level of sound for the front speakers, is all the way down! Otherwise, you could generate painful feedback!

      This happens because the sound coming out of the speakers enters the microphone, which comes out of the speakers, which enters the microphone, etc., at each stage reinforcing the amplitude of the signal.

      Always make sure the speakers are off while recording!

    • Make some noise into the mic, to make sure you see level in the meters.

Recording

  1. Record your first sound in Adobe Audition.
    • In the Mac’s Dock, click the Audition icon to launch the program.
    • You may need to log in to Adobe Creative Cloud. Use your iu.edu email address to do so. Once you enter this, you will see the usual IU Login screen.

      If you have already logged into Creative Cloud on more than one computer, it will ask you to relinquish one of them. (This is temporary.)

    • An empty document opens.

      Click the red circular record button in the Transport panel.

      A dialog box appears, requesting that you name the sound file and choose the sample rate, the number of channels, and the bit depth. Choose Mono, and Change the bit depth from 32 (float) to 24.

      After you press OK, recording begins immediately.

    • Make some noise into the mic. While Audition records, watch the levels on the meter in Audition, and set your recording level. To control the level of signal reaching the computer, use the sub out 1 fader (labeled MOTU IN 5) on the mixer.

      Aim for peaks no higher than about -3 dB in Audition. It’s okay if your peaks are rarely above -12 dB. If they are much less than this, your level is too low. Or you’re recording a sound that is inherently soft, such as whispering or pins dropping. These guidelines are just rough rules of thumb.

    • Once you have a good level, stop recording. (Press the space bar.)

      Choose File > Undo to remove the recorded material.

    • Press the record button again to record for real this time.
    • Save your file now (using File > Save), but don’t play your sound yet!
  2. Listen to your recording.
    • On the mixer, make sure you have the mic channel muted (MUTE button) while playing back your sounds!

      This is to prevent feedback between the mic and speakers. (Do you see how this can happen?)

    • The sound will come from the computer via the MOTU Analog 1-2 mixer channels, which are channels 9 and 10. Raise both faders to unity.
    • On those input channels, engage the L/R buttons to assign the signal to the main mix (i.e., “Speakers L/R”).
    • In the mixer’s output section, raise the “Speakers L/R” fader at the far right.
    • Play back your sound in Audition. (Press the space bar.)
    • Before you resume recording, turn the speaker fader down all the way, and unmute the mic.
  3. Record more sounds.

    To record into a new file, choose File > New > Audio File.

Ending your Session

  1. Tidy up! At the end of your session...
    • Turn off phantom power, wait a few seconds for the power to wane, then disconnect the mic(s) from the mixer.
    • Coil cables neatly, binding them with the Velcro strip, and return everything to the file drawer (cables on top of the mic box, not below it).

      Practice coiling cables, using this video as a guide.

    • Zero out the mixer.
    • If you are likely the last person to use the studio for the day, please power down the studio, but not the computer. Do log out of the computer. Make sure the fluorescent lights are on first, or else you’ll be left in the dark! Then press the gray “Turn Studio On Here” button once. Everything except the computer will power down.

Submission

  • Select your best recording of each of the four types of sound mentioned above (in the Choosing Sounds section), making sure that they are in this format:

    Broadcast Wave
    Mono (single-channel)
    44.1 kHz sampling rate
    24-bit resolution

    Each recording should be no more than about 30 seconds long.

  • Follow the assignment submission instructions to submit your recordings using Canvas.

    Keep the recordings in your account on the MC304 computer.

Grading Criteria

This assignment will receive a letter grade based on the following criteria. The highest grade is A. There will be a one grade-increment deduction (e.g., from A to A-) for each of the following problems, except for the first, which counts two increments.

  • missing recording (should be four) [2 increments]
  • a sound that doesn’t reasonably fit the four types mentioned above
  • clipping, where the meter goes into the red, and the waveform is flattened off at its top and/or bottom
  • really low-amplitude waveform, unless the sound is inherently very soft (e.g., whispering, pin drop, etc.)

Any other problems are forgiven. But please leave silence between performances of your sound-making object.

Manuals

Manuals for the Mackie 1604 VLZ mixer and AKG 414 microphones are in the Manuals folder on your Desktop.

For more detailed help with Audition than the assignment guidelines provide, consult the manual.

Course content is copyright ©2009–2024 John Gibson, Alicyn Warren