My First Sound System

Christopher Plummer Full Class Period Exercise, Introductory, Project

Students put together sound systems in small groups and demonstrate basic vocabulary and drafting standards individually.

Recommended Class Size:

This depends on the amount of equipment available. I split my class of 20 in two so I have 10 students that are then broken into 3 groups of 3 or 4.

Activity Objectives:


Given the opportunity to work in small groups wiring a sound system to a given specification students will demonstrate positive interaction in collaborative problem solving measured through instructor observation and the success of all group members on the individualized written component.
Translation: Did the group set-up the system or one member of the group? The instructor needs to watch and perhaps step in and redirect groups where one person is doing the set-up and the other students are not engaged.

Given a description of a sound system and the necessary equipment students in groups of 2 to 3 will assemble a small sound system.

Using their assembled sound system students will demonstrate:

  • The use of an equalizer to increase intelligibility
  • Effective use of a gate
  • Mitigating a sound source problem using a compressor
  • One way a sound system can decrease intelligibility

After assembling a sound system each student will demonstrate his or her understanding of the groups set-up by drafting a block diagram.

When documenting their sound systems students will show understanding of signal flow by drawing arrows indicating signal flow on all cables in their block diagram.

When documenting their sound system students will employ professional standards of audio drafting in creating their block diagrams. This applies to the drafting detail as well as the titles and aesthetic presentation.

From the in-class instructor and group demonstrations each student will, in a short written answer, demonstrate understanding of the following terms:

  • Serial processing in analog audio
  • Parallel processing in analog audio
  • Pre-fade auxiliary send
  • Post-fade auxiliary send
  • Insert point
  • Intelligibility

Description:

Overview

In groups of 2 to 3 students will assemble a sound system from a written description.

The instructor will use one of the constructed systems to demonstrate several key concepts:

  • Using EQ for vocal intelligibility
  • Using compression to tame dynamics
  • What happens when gates are set incorrectly
  • The difference between pre- and post-fade sends

Based on this demonstration (and earlier class work) each group will creating the following sound examples:

  • Poor intelligibility
  • EQ set-up for good intelligibility
  • A well set-up gate
  • Effective use of compression
  • Two different examples of digital effects

Based on notes taken in class each student will do a block diagram of the sound system and in writing answer key conceptual questions about the activity.

Preparation:

You must collect enough equipment for groups of up to 5, but ideally 3, to each put together a sound system. Each group requires:

  • 1 microphone
  • 1 mixer
    • Must have an insert point and pre and post fade auxiliary sends
  • 1 compressor
  • 1 reverb/digital effects processor
  • 1 speaker
    • There is no need to do stereo for this project and doing it in mono often opens up the opportunity to talk about when stereo is appropriate and when it isn’t. For example even though students only have one speaker they usually try and wire their digital effects unit in stereo until they are asked why they are wiring it that way.
  • It is recommended that each group also have one graphic EQ
  • Cables to make the above work
  • An example of sound system drafting.
    • I recommend using the proposed student drafting standards available from the USITT sound commission on the USITT web site.

Before students attempt this project they should have been given definitions of Serial Processing, Parallel processing, intelligibility, and been introduced to audio drafting standards and examples.

In order to make this project more affordable I usually break my class in two and ½ the class watches an instructional video while ½ of the class does this project and then the next class we switch. This also limits the number of students that I am watching.

Distribute you weak and strong students evenly. A group made up of all weak students will not make it through this project (unless you are doing it late in the semester).

Student Instructions:

During class you and one or two partners will set-up a sound system and will receive 25 points for making it work and creating some interesting sounds with the processors. Your system will consist of a microphone, a mixer, two serial processors (compressor and EQ), a parallel processor (reverb), an amplifier and a speaker. Your compressor must be inserted on your microphone channel while your EQ must be wired in between your mixer and your amplifier.

The remaining 75 points of the assignment will be earned by individually creating a diagram of the signal flow of your sound system and answering a few questions. You will be given system diagram examples to refer to. You will be required to:

  • Label all inputs and outputs with their correct names (ie. Aux 1). Labels must be neat and inside the equipment clearly associated with a contact point. (17 points)
  • Every piece of equipment in your system should be labeled (Make and Model). The labels on your drawing must be clearly associated with the piece of equipment and provide enough information for some one to set-up the system. (15 points)
  • You must have a bounding box for the drawing and a title block with the project name, date, the names of every one in your group, and your name as the individual who did the drawing. (7 points)
  • Have a clear direction of signal flow. Your drawing must follow the left to right signal flow convention where possible and include arrows on all cables clearly indicating signal flow. (10 points)
  • Produce a clear and attractive drawing (can be drafted on the computer or by hand but not freehand). (6 points)
  • On a separate page answer the following questions (20 points):
    • Explain serial and parallel processing.
    • Explain whether you would use a pre- or post-fade send with a digital effects unit.
    • What is an insert point and why is it useful?
    • What is intelligibility and how could your sound system increase or decrease it?
During Class

Walk the room and provide assistance – try and use guiding questions so students ‘discover’ the answers for themselves.

Remind students (many times) to take careful notes and ask questions so they are prepared to do their block diagrams and write responses to the questions.

Demonstrate that a pre-fade send to the reverb doesn’t fade out when you fade the microphone channel. And demonstrate that a post-fade send maintains a ratio of direct and processed sound.

Shout and whisper into the microphone and demonstrate good and bad settings on the compressor. What it can help with and what can go horribly wrong. This is introductory so don’t get too detailed. Focus on keeping shouting from being painful and a gate closing too much and removing words.

Encourage students to play with some of the stranger effects on the digital units. Doing a demo of a strange digital effect can often start a burst of playing where students discover tools available for sound design.

After Class

Put the equipment away and grade the student’s drafting and short answers based on the rubric that is part of the instructions.

Time Length

This should take a relaxed 90 minute class.

Required Materials

You must collect enough equipment for groups of up to 5, but ideally 3, to each put together a sound system. Each group requires:

  • 1 microphone
  • 1 mixer
    • Must have an insert point and pre and post fade auxiliary sends
  • 1 compressor
  • 1 reverb/digital effects processor
  • 1 speaker
    • There is no need to do stereo for this project and doing it in mono often opens up the opportunity to talk about when stereo is appropriate and when it isn’t. For example even though students only have one speaker they usually try and wire their digital effects unit in stereo until they are asked why they are wiring it that way.
  • It is recommended that each group also have one graphic EQ
  • Cables to make the above work
  • An example of sound system drafting.
    • I recommend using the proposed student drafting standards available from the USITT sound commission on the USITT web site.

How can I afford this?

  • Arranging the class in groups means less equipment is needed.
  • Half the class can watch a video or do a different project further limiting the number of set-ups you need to provide.
  • Carefully schedule this activity between shows so you can raid all of your performance spaces for equipment.
  • Make sure any equipment purchased for this activity is useful elsewhere.
  • Buy really cheap equipment! Audio fidelity isn’t important for this assignment. Note: this probably violates principle number 4.

Evaluation

Informal Evaluation
  • This project will allow you to observe students working through technical challenges. Watch for:
  • Who demonstrates prior knowledge
  • Who takes charge of groups
  • Who helps other members of their group understand what is going on
  • Who asks the group questions when they don’t understand what some one else did
    • This one is very important as not all group members may be working on the same issue.
  • As you listen to the questions are students asking to learn about the audio system or are they simply taking the notes they need to pass the written part of the assignment.
Formal Evaluation

The formal evaluation is clearly spelled out in the instructions given to the students. The rubric divides the project into the in-class group portion and the take home individual portion.

The group portion is graded on whether each group has a working sound system by the end of class. Class is structured so that every student will get full points on this part of the assignment. It would be possible to be more formal with the presentations and to assign individual points to each group for presenting key concepts with there sound system. This would largely be dependent on when in the semester students do this project. When done early in the semester it is best to keep the in-class portion low key on the presentation side and high encouraging students to play with the sound system. Later in the semester, or based on your teaching style, it may be useful to be more rigorous in the presentations.

If you feel the need to tie graded evaluation to the affective domain objective you could assign a few points of the group success to reflect the quality of individual work turned in. For example, for groups to get the full 25 points of group success all students individual work must be A quality, if the average of student work is a B then the group only gets x points of group success.

During the group portion of this project instructor feedback is essential. Students will make mistakes or will be have trouble

The individual portion of the assignment is broken into many small specific benchmarks. Each aspect of the drafting is assigned a certain number of points and each written question is assigned points.

  • Label all inputs and outputs with their correct names (ie. Aux 1). Labels must be neat and inside the equipment clearly associated with a contact point. (17 points)
  • Every piece of equipment in your system should be labeled (Make and Model). The labels on your drawing must be clearly associated with the piece of equipment and provide enough information for some one to set-up the system. (15 points)
  • You must have a bounding box for the drawing and a title block with the project name, date, the names of every one in your group, and your name as the individual who did the drawing. (7 points)
  • Have a clear direction of signal flow. Your drawing must follow the left to right signal flow convention where possible and include arrows on all cables clearly indicating signal flow. (10 points)
  • Produce a clear and attractive drawing (can be drafted on the computer or by hand but not freehand). (6 points)
  • On a separate page answer the following questions (20 points):
    • Explain serial and parallel processing.
    • Explain whether you would use a pre- or post-fade send with a digital effects unit.
    • What is an insert point and why is it useful?
    • What is intelligibility and how could your sound system increase or decrease it?
Hints for Success

Remind the students to review the material required on their drawings frequently while they have their systems set-up. If you don’t they will not take the notes they need to be successful.

Encourage the students to play with the sound system. The EQ and digital effects can be particularly fun and can open up their ears to new possibilities. This is not a time to talk about nuance and artistic integrity.

Christopher Plummer, Michigan Technological University

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