The Sound Bible
The Flow of Sound 2
1/4 inch audio jack
1/8 inch audio jack 3
Wireless Microphones 8
The Soundboard 10
Overview of Function 14
Control Channels 15
The Flow of Sound
● Sound first is picked up by a microphone and converted to an electrical signal
or a signal is provided by an electrical device (such as a phone).
● Stage Ports
○ These XLR ports are connected to the patch bay in the light booth.
○ At the patch bay the signal goes into the stage box, which compiles all
of the electrical signals into a digital signal.
○ The single cord carrying the digital signal connects to the soundboard,
which directs this into all of the original electrical signals.
● Wireless Microphone
○ Wireless mic packs and handheld mics convert the electrical signal
through into radio signal.
○ Antenas by the sound board pick up the various radio signals produced
by all of the wireless mics and send them to the receivers.
○ The receivers, which are underneath the soundboard are tuned to a
specific radio frequency and they receive the signal transmitted on that
○ The receivers are each connected individually to the sound board.
○ The electrical signal is send directly to the soundboard.
● At the soundboard the audio is altered, and then all of the outputs are
compiled into a single digital signal and sent to the patch bay.
● At the patchbay the digital signal is dissected into individual outputs by the
● From the stage box the outputs are sent to the proper amplifier. These increase
the amplitude and power of the signal so it is enough to power the speaker.
● After the signal is amplifies it is sent to the proper speaker.
● At the speaker the electrical signal is converted into sound we can hear.
● This is the most commonly used cord for sound. It usually has 3 pins (but can be
found with up to seven), positive, negative, and ground. Sound travels out of
male into female connectors.
● Extra pins are used to transfer power, have two way audio transfer, or other
applications. (Headsets have four, our omnidirectional mics have seven).
● Mini XLR also exists for applications with limited space, such as the pencil mics.
1/4 inch audio jack
● Used for many output and input needs, such as guitars and amps, and smaller
sound boards. Professional headphones also use this connector. Usually only
male connectors are used with devices, which have female ports.
1/8 inch audio jack
● Used for smaller output devices, such as phones.
○ This is the most common pickup pattern.
○ The microphone picks up sound best right in front of
it, and basically none at all directly behind it.
○ Our handheld mics are cardioid.
○ This is a difficult pickup pattern to obtain and therefore it is
○ The choir mics we have are omnidirectional, along with our
○ These microphones pick up sound on two opposite sides of
○ They usually have some component that separates the two
sides of the mic.
● These are the most common type and most durable.
● They work by having a diaphragm that is connected to a coil of wire which
vibrates past a magnet when sound hits the diaphragm.
● This system produces an electrical signal, so additional electrical power is not
● Dynamic mics work best when fairly close to the source, they don’t pick up
sound like our ears.
● Most likely have a cardioid pickup pattern.
● They are not the best when fine detail or general ambience is needed to be
● All handheld microphones we have are dynamic.
● These are more responsive and do much better at picking up details than
● A capacitor works by storing electricity in the space between two metal plates.
These microphones work by having one of the plates attached to a diaphragm
do when sound hits it and moves the plate, the electrical signal changes
● Condenser mics have the benefit of being able to pick up mics in
omni-directional and bidirectional patterns, along with cardioid.
● Unlike the dynamic mics, condenser mics require additional power to work.
● This additional power is called “Phantom Power” and is 48 volts.
● Usually the sound board provides this power.
● Our lavalier mics, pencil mics, and omnidirectional mics are all condenser mics.
● The frequency that is transmitted can be adjusted on the microphone and the
frequency a receiver “listens” on can also be adjusted. These must be the same
for a microphones sound to be picked up by a receiver.
● If two microphones are transmitting on the same frequency, the signal gets
warped and the signal is not clearly transported, resulting in strange sounds.
● Many devices produce radio signals, so frequencies must be chosen so that they
don’t have interference.
Reading the Receivers
● The largest number is the frequency of the receiver shown in megahertz. Use
this to compare with the other recievers; if two frequencies are too close
together they can interfere with each other.
● Above this number we can see the number 15.8. This is the “frequency bank”
selected. Frequencies are divided up into multiple banks and slots, in the image
bank 15, slot 8 is selected. The exact selection doesn’t matter, but it makes it
easier to communicate.
● The leftmost meter shows the strength of the radio signal. If this is high that
does not mean that any audio is being received, rather that a connection is
● If a microphone is nearby and on, the RF should be all the way up.
● When it goes really far away, such as the dressing room, the RF will look more
like when the microphone is off.
● When the microphone is off, the RF should be all the way down. If there is
substantial RF when the microphone is off, that means there is the potential for
● When RF is below a certain threshold, the receiver automatically mutes the
● The second meter is audio signal. This is the sound signal volume that is being
received, shown in decibels.
● There does not need to be a strong radio signal to receive audio.
● If there is a lot of AF when the microphone is off, there is interference and a
better, cleaner frequency should be selected.
● The top of the meter will light up when the audio “peaks.” This means it is so
loud, the audio signal can’t be completely communicated, so it can become
“crackly.” If this is happening the sensitivity of the transmitter can be reduced.
● When properly calibrated, a microphone should rarely, if ever peak.
● A sign a microphone is broken, without listening to the audio from it, is if it is
● If there is a substantial radio signal the receiver will display the battery level of
the transmitter, shown in thirds.
● If the battery level is displayed the receiver has a considerable connection with
● If the battery is not shown the transmitter could be dead, but the more likely
reason is the microphone is simply out of range, such as the dressing rooms.
● Hillcrest has two models of lavalier microphones usually referred to as “black”
● The tan microphones are Point Source CO-8WS omnidirectional microphones.
These microphones produce a much clearer sound and are higher quality than
the black microphones. The have a rigid boom that stick out along the side of
the wearer’s mouth. Avoid bending this or adjusting it as it can be very fragile,
and if this component breaks it can’t be fixed.
● The black microphones are not stiff, and have a lower sound quality, however
the audio can be improved with proper utilization of an equalizer.
● When connecting the headset to the “mic pack” the connector should be
securely screwed until it can be screwed further. This is the component most
likely to break, so it needs to be secured and not bent when placed in the belt.
Taping the Microphones:
1. The first piece of tape should be placed next to the mouth.
When the wearer smiles, the end of the microphone should
stick out just past where their skin folds, right where the upper
and bottom lips meet. If is sticks too far in front of this line, the
microphone will pick up the breath of the wearer. The tape
should be placed right behind of the microphone.
2. This piece of tape should be placed behind the ear, below where the stiff
section of the microphone ends. This piece of tape should keep the mic securely
positioned around the ear of the wearer, without uncomfortably distorting the
3. This final piece of tape is optional, but recommended. It provides additional
restriction of movement. It should be placed on the middle of the neck, towards
the bottom. When placed, the wearer should turn their head all the way to the
right to prevent the tape from being pulled off when their head is turned.
Understanding all of the capabilities of the soundboard and how to effectively
use it is the most difficult area of sound. There is a lot to know in order to go from
being able to turn on a mic, to mixing together multiple microphones and inputs,
making them sound good, and sending them out to various speakers and outputs.
The board Hillcrest has is an SI Expression 3. It is digital board. On analog
boards, each dial and fader only has one purpose, and it does not change. With
digital boards, the function of all the controls can be customized, and changed. This
means that is can do more with fewer controls and a smaller board.
1. Control Channels 7. Bus Selector/Fader Follow
2. Control Channel Encoders 8. Assignable Channel Strip
3. Solo Controls 9. FX controls
4. Faders 10. Touchscreen Interface
5. Main Mix Control 11. Metering and Monitoring
6. Cue Controls
Overview of Function
Before jumping into individual components is important to understand how a
soundboard like this functions. First and foremost, you must understand how fluid and
changing the board is. Faders, dials, and buttons can all change their function.
Looking at the soundboard you can only see 30 faders, along with the two main mix
masters, but the board actually has four times as many controls. There are multiple
“layers” of faders, which can be changed with the fader selector. When a different
“fader” is selected, that is a different
layer of controls. It is sort of confusing
because the individual sliders are called
faders, and the layers of these are also
called faders. Therefore, to differentiate
they will be called sliders and faders,
respectively. So, layers of sliders can be
accessed by changing what fader you
are on. All of the inputs and channels
controlled when fader A is selected are
completely separate from the inputs and
channels that are controlled when fader
B is selected, etc. Along having four
faders, the sound board also has two
additional layers that function as
equalizers that will be discussed later. This structure is illustrated in the image.
Another important concept to understand is how sound is outputted. The
different outputs can be called “Mix Buses.” A mix takes sound from certain inputs,
alters it, and then sends it to a single output. On the soundboard there is a “Main
Mix,” this is the master. When no mixes are selected, you are controlling the main mix.
The sound from this is sent to the master LR and Mono channels, which we have set
up as the house speakers. The soundboard can also “bus” sound to multiple other
outputs, each of these collections of channels, settings, and inputs is another mix.
A control channel is the collection of dials and buttons, along with the slider,
that control a channel/input.
This is the slider that controls the output level of the channel. The measurement
along the slider are how much it is adding/subtracting from the input level. At the
bottom is the infinity symbol, meaning it is subtracting infinite decibels, so it outputs
no sound. Further up the slider is the 0 mark, this means that it is outputting the exact
level of the input. It is referred to as “Unity,” and this it is when the slider is here that
the audio level should be what is desired. You might be asking, if a microphone is so
loud that the sound is way to loud when the slider is as unity, what do you do then?
That is where gain comes into play, which will be discussed later. After the slider goes
past 0, or unity, it is adding decibels onto the output level.
Along the side of the slider there a light strip that helps communicate what
type of channel it is or how it is controlling it. The key for what each color means is:
The soundboard has monitoring capabilities that are enhanced by the ability to
solo certain channels. Underneath the bottom left corner of the board there is a port
for headphones. When no channels are being SOLOed, the soundboard will send the
audio from whatever mix is selected, with all of the alterations, to the headphones.
When the SOLO button of a channel is pushed, the audio from only this channel will
be sent to the headphones. Multiple channels can be soloed and be listened to at a
time, which is extremely useful when trying to troubleshoot issues. For example, if
there is a crackling sound being heard, you can solo out each microphone individually
to determine which one is the cause.
This function has the quirk that if only one channel is being SOLOed, it will
send the audio level if the slider was at unity, regardless of where it is or whether the
channel is even ON. This is called PFL routing. This is also extremely useful because it
allows the soundboard operator to listen to a microphone for issues and troubleshoot
without turning it up for the whole audience to hear. Once more than one channel is
selected, only levels that are actually being outputted will be send to the headphones.
This is called AFL routing. The volume of the headphones or “monitor” can be
adjusted with the dial labelled “monitor” in the top right corner of the board. Above
this dial there are lights that indicate what type of routing is being using.
Additionally, all SOLO selections can be cleared with the button labelled “SOLO
CLR” above the FADERS buttons.
This is the Select button. When this button is hit, the entire Assignable Channel
Strip, along with controls on the touchscreen all control whatever channel has been
selected. Only one channel can be selected at a time. The master slider for each mix
can also be selected. This button is also used with the “Interrogate” function of some
other buttons, which is explained later.
This button, simply controls whether the channel is on or not. If a channel is not
on no audio will be outputted from it.
These lights display that activity of the gates and compressors that control the
channel. They will be discussed in the section for the Assignable Channel Strip and the
Gate and Compressor sections.
This is a dial that can control one out of the following three characteristics:
Gain, Pan, or the High Pass Filter. Generally, the most useful option is the Gain, and
this is what will usually be selected. The selection can be changed with the three
buttons to the right of the encoders.
Gain is the very first alteration to the audio that is inputted. It either subtracts,
or usually adds to the amplitude of the audio signal, measured in decibels. It is also
the first thing that should be set for a channel because all other settings are reliant
upon the level determined by the gain. Gain can only be set in the Main Mix.
This collection of buttons determine what “layer” of channels and slider is being
controlled. There are four faders and two layers that control a Graphic Equalizer.
Each fader has a default setup which can later be changed. That default setup is
While this is the default setup, the function of each slider across the four faders can
The Graphical Equalizer or GEQ can be accessed with two bottom buttons of
the FADERS section. It is only available if a mix master is selected using the SEL
button above the slider. This equalizer is split into LO and HI, each having 14 ranges
that can be controlled for a total of 28 levels of control for the equalization of the
mix. Equalizers will be further explained in the Assignable Channel Strip section.
This section of the soundboard contains all of the buttons for the different mix buses.
When one of the mixes is selected, the control channels will light up and now control
the levels sent to that particular mix.
Pre and Post Fade
Each mix master, along with each individual channel, has the option of being set as
either a post fade or pre fade.
Post fade means that the input into that mix is the output from the main mix.
For example, if the slider in the main mix is set to -∞, none of that channel
audio is being outputted, so in a mix set to post fade, no matter what the levels
are at, nothing will be outputted out of the mix being nothing is being inputted.
This is useful when you want the output of two sources to match, and so you
don’t have to change levels in the mix when they are changed in the main mix.
Often post fade is used and all of the sliders in the mix are set to unity so that
the mix output matches exactly the main mix.
Channels that are set to post fade will glow green.
Pre Fade means that the input is directly from the source; the main mix and the
mix are getting the same input for that channel and altering it differently. This
is useful for when you want the output of a mix to remain constant regardless
of changes in the main mix.
Channels that are set to pre fade will glow yellow.
The type of fade can be chosen if the channel or mix master is selected. Then, in the
INPUT menu of the touchscreen interface, the fade setting for each mix can be