Download Basic sound Mackie24-4

Welcome to Ebenezer’s
Sound Tech Training
I’m sure this thing worked last Sunday
The Importance of Acoustics
What did he say?
The Effects of Too Much
REVERBERATION
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Impacts spoken word more than music.
Impacts those with hearing loss the most.
Makes certain words difficult to understand.
Causes listener fatigue.
How To Control
REVERBERATION
• Use construction techniques which
minimize reflections.
• Aim speakers to focus sound away from
ceiling and walls.
• Use equalization to reduce frequencies
which naturally resonate in the room.
As A Sound Tech,Your Biggest
Mistake is Adding Too Much
Bass
Or having stage monitor levels
set too high
The congregation needs to
listen to the main speakers,
not the monitors!
Always Check out the system
before the service….
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Mixer controls set normal.
Mikes connected and working.
Instruments connected and working.
Monitor speakers aimed correctly.
Wireless batteries in good condition.
Service tape loaded and ready to go.
Two minutes prior to start of service is NOT the ideal
time to begin a trouble-shooting process!
Mark
POWERING UP THE SYSTEM
ON FIRST
OFF FIRST
Avoid damaging “POPS” - always
turn power on or off in the order
indicated!
NEVER CONNECT OR DISCONNECT
MICROPHONES OR INSTRUMENTS….
Unless the channels are muted or
the system is off.
Pops, clicks, and buzzes can damage speakers!
Always use the right cable!
Small round shielded cable for instruments
Large flat unshielded cable for speakers
Examining Signal Flow
It All Starts Here…
DI Box
Mixer
The Big Picture
Peavey
From Signal Sources
AUX-2
70 Volt Amp
Fold-back
Speaker
70 Volt Amp
Class
Speakers
Bogen
MAIN
AUX-1
Mackie
EQ
CONTROLLER
Peavey
Tannoy
Main
Speakers
Tannoy
EQ
Monitor
Speakers
Peavey
Yamaha
Peavey
Class Speakers actually consist
of...
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Two speakers in the Narthex.
A speaker in the nursery.
A speaker in each of the young kids rooms.
A speaker in the kitchen.
Each room has its own volume control
located in the room.
DON’T MESS WITH THE
GRAPHIC EQUALIZERS!
You can cause real problems with the system.
Setting them requires the proper test equipment!
The Mackie SR24-4 Mixing
Console
TWO IMPORTANT SWITCHES
Master Power
Phantom Power
Both must be on at all times!
Mixer Rear Panel, lower left corner
What is Phantom Power?
• Low voltage applied to the mike lines by
the mixer.
• Used to power electret mikes and active
direct boxes.
• If the switch is off, choir mikes, podium
mike and Peavey direct boxes will be dead.
The Mono Channel Strip
Learn one and you know all twenty.
Signal Flow
Top to Bottom
The TRIM control
• The first stop for the signal at the mixer.
• Sets the overall level of the signal going
to the rest of the mixer circuitry.
• Compensates for differing levels of
various input devices.
• Proper setting is essential to low noise
and ample “head room”.
TRIM Control Warning!
TURN DOWN THAT TRIM!
If the red OL light comes on
then your trim control is set
too high!
What is ample HEAD ROOM?
No, its not having enough rest rooms on a ship!
Clip
Signal Level
Head Room
Normal
Noise
Time
Clipping Causes Distortion…..
Clipping
Signal Level
Clip
Normal
Noise
Time
…..and distortion can blow your speakers!
Yikes!
Hard Feedback Can Toast your
speakers too
If you go “ouch” after that last squeal, chances are so
did your speakers!
and so can pops, clicks, and
buzzes
caused by plugging/unplugging hot mikes or instruments!
Always mute the channel at the mixer first!
Ways to set the TRIM Control
The Traditional Way….
TRIM?
Back down from
clipping and hope
for the best.
Or…..
The MACKIE Way
sets the gain structure accurately
by using the VU meter lights
• Channel SOLO button down.
• SOLO MODE in Pre-fade (Up).
• Adjust TRIM for zero on the VU Meter.
The AUX 1 Control
• Controls how much channel signal is sent
to the stage monitor speakers.
• Always Pre-Fade, which means it is ….
• not affected by the channel EQ.
• not affected by the PAN control.
• not affected by the channel fader.
• affected by the MUTE control.
AUX 1 (Monitor) Rule
Never mix choir mikes into
the stage monitors!
Feedback will be too
difficult to control.
I wish I hadn’t done that!
The AUX 2 Control
• Controls how much channel signal is sent
to the stage fold-back speaker.
• Like AUX 1, it is always Pre-Fade.
• Used to send voice to the front edge of
the stage.
• Speaker does not have the frequency
range to handle music.
The AUX 3 Control
You get a break - we don’t use it!
The AUX 4 Control
• Controls how much channel signal is sent
to the CD/TAPE machine for recording.
• Used in post-fade mode (PRE button up)
so that the signal….
• Is controlled by the channel fader.
• Is processed by the channel EQ.
• Is affected by the PAN control.
• Is affected by the MUTE control.
.
Please make sure the
PRE button is out.
This places AUX 3 and
AUX 4 in the post-fader mode.
The AUX 5 Control
• Controls how much channel signal is sent
to the SERVICE TAPE MACHINE.
• Always post-fader.
Today’s Sermon
The AUX 6 Control
• Controls how much channel signal is sent
to the VCR.
• Always post-fader.
Joe’s Rental Video
The Channel EQ Controls
• Make minor adjustments to
tone quality of the channel.
• Does not affect monitor or
fold-back speakers.
• Straight up (U) is flat (no EQ).
• For microphones always cut,
never add.
Use EQ Sparingly!
U
EQ
One or two tick marks is usually enough.
On Microphone Channels
Always cut, never add EQ
It avoids feedback
The HI EQ Control
Controls High Frequencies
Too much high - cut a little
The LOW EQ Control
Controls Low Frequencies
Too much bass - cut a little
The MID and FREQ EQ
Controls Work Together
• MID controls the amount of
add or cut.
• FREQ controls the frequency
to be added or cut.
• Set MID then sweep FREQ to
get the desired effect.
If you get confused…..
Just put the EQ knobs to their
center positions. The system
should sound acceptable with
the EQ flat.
The LOW CUT button reduces very
low.frequencies.
Depress it to reduce handling and
wind noise on hand-held, wireless
and pulpit mikes.
Leave it up for choir mikes and
instruments.
Now lets take a look at the
Mackie video….
and learn more about how EQ works
Note: The mixer in the video is different than ours
but it demonstrates the concept of EQ very well.
Volume
The Graph you’ll see on the
video….
Bass
Treble
Frequency
20 Hz
20,000 Hz
Mackie Video Review….
• We have only one mid EQ covering 100 Hz
to 8 KHz.
• Our bandwidth is fixed at 1.5 octaves so
there is no bandwidth control.
• The concept is the same as in the video.
• The HI and LOW EQ are the same.
• The LOW CUT filter is the same.
Continuing with our SR24-4….
The PAN Control
Since we combine the mixers
left and right stereo channels
into a single monaural output,
the PAN controls do nothing.
Simply leave the PAN controls
centered.
The Red OL Light
You’re Clipping!
TURN DOWN THE TRIM!
The Green Signal Light
You have signal - all is well….
The MUTE Button
• The only way to completely
disable an input….
• Always mute unused
microphones.
• Always mute before
connecting or disconnecting
input devices.
The SOLO Button
• Sends the channel to
headphones and VU meter.
• Good for troubleshooting.
• Used to set TRIM control.
• Can be used to set mix.
The L-R Button
Signal Buss Company
If you don’t assign the channel to a
BUSS, the signal won’t go anywhere!
For simplicity, always assign to the
main L-R buss.
The FADER Control
• Controls how much signal
goes to L-R and Post-Fade
AUX outputs.
• Used to set mix into main
speakers.
• Usually falls near “U” mark
if TRIM is set properly.
Now you know how to control 20 of the 24 channels
Only 4 more to go!
The Stereo Channels
• Channels 21 and 22 are combined.
• Channels 23 and 24 are combined.
• Used to combine stereo output from
tape and CD machines.
• The only difference from mono
channels is in EQ and use of the
PAN control.
The EQ Differences
Instead of swept EQ for the mid
range, channels 21/22 and 23/24 have
separate HI MID and LOW MID
controls.
Set these for the desired effect just
like you do for the HI and LOW EQ
controls.
Special PAN Control use
• Normally set to center.
• For Kids Choir split-track tapes
pan left or right to send only the
music track to main speaker
while voice and music tracks go
to monitor speakers.
Now for the output side of the mixer.
Don’t let it scare you - we don’t
use most of it!
There are 6 AUX SEND MASTERS
One for each buss. Remember….
1 - Stage monitors.
2 - Fold-back monitor.
3 - Not used.
4 - CD/Tape.
5 - Service tape recorder.
6 - VCR record.
Signal Buss Company
Channel AUX
AUX SEND
The channel AUX determines how much signal
gets on the buss.
The AUX SEND MASTER determines how much
signal gets off the buss.
Need more keyboard in the monitor mix - turn
up AUX 1 on the keyboard channel.
Need more of everything in the monitor mix turn up the AUX 1 SEND MASTER.
Each AUX SEND
has a SOLO button.
Want to hear what’s going to the
monitor speakers? Press the AUX 1
Send Master SOLO button. You’ll hear
the whole mix.
The VU Meter also reads the level of
the signal going to the monitor speakers
while the SOLO button is pressed.
The VU Level Meter
• Used to measure signal levels.
• Main L/R Output if no solo
buttons pressed.
• Channel Signal when a solo
button is pressed.
The RUDE SOLO Light
Flashes to warn you when the VU meter is
reading a SOLO channel signal, rather than
the main L-R signal.
The SOLO LEVEL
Sets the level of signal coming over the solo
buss.
Normally, set it about half way (U).
The SOLO MODE
• Determines if the individual
channel solo is taken before
or after the fader control.
• Normally left in the post
fade AFL (down) position.
• Exception when setting
TRIM controls.
Never Press These!!!
Pressing TAPE RETURN TO PHONES will
kill all headphone output.
Pressing TAPE RETURN TO MAIN MIX
will kill all main speaker output.
Disappearing Sound
PHONES/C-R LEVEL
Adjust for a comfortable headphone
level.
Note: C-R stands for Control Room.
MAIN MIX FADER
Adjusts the overall level going to the
main and classroom speakers.
Adjust talkback level here
Push MAIN MIX for main speakers
Push AUX 1&2 for stage and foldback speakers
TALKBACK
• Sends console mike to main,
stage, and foldback speakers.
• Sound Tech can talk to Choir
Director during rehearsals.
Now for some accessory items….
Dynamic Microphones
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General purpose hand-held.
Working range 3 to 6 inches.
Good for solos and small groups.
Low output - trim above 3/4 full.
Requires no phantom power from mixer.
Electret Microphones
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Condenser element with built-in preamp.
Requires phantom power from mixer.
Used for choir and pulpit.
Sensitive - working range 2 feet or more.
Exhibit bass when you get too close.
High output - Trim set between 1/4 and 1/2
full.
Wireless Microphones
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There are two wireless receivers.
There are three wireless microphones….
One receiver works with a lapel mike.
One receiver works with the other lapel
mike OR the hand-held wireless mike,
never both!
Use only name brand alkaline or lithium batteries
in the wireless mikes!
Neveready discount
battery
I’m sorry
The Telex Wireless Receivers
Signal Light
Diversity Light
The Telex Wireless Receivers
Diversity
Light
Signal
Light
• Signal light indicates RF signal received.
• Diversity changes orange/green to indicate
antenna receiving the best signal.
The Diversity Receiver
Reflective Surface
A
B
Direct and Multipath signals cancel at antenna B.
Receiver picks antenna A which still has a good signal.
Receiver Squelch Control
• Not a normal sound tech adjustment.
• Located on the rear of the receiver.
• Cuts receiver off to prevent “hiss” when no
RF signal is present.
• If set too high, sound will chop off as mike
is moved about.
• If set too low, “hiss” will be present when
transmitter is turned off.
Observe the 3 to 1 Rule for
Microphone Placement
1 FT
3 FT
The distance between microphones is at least 3 times
the distance between the singer and his microphone.
Why the 3 to 1 Rule?
• Minimizes picking up the same sound with
multiple microphones.
• Minimizes Comb Filtering effect which….
• Often causes a “hollow” sound.
• Causes sound to change with movement.
When two or more microphones pick up the same
sound source from different distances, Comb-Filtering
is the result.
Due to the difference in sound travel time, certain
frequencies cancel when combined at the mixer.
Comb-Filtering makes the signal sound “hollow”
Volume
Comb-Filtering….
“like the teeth of a comb”
Bass
Frequency
Treble
Choir Microphone Placement
6 - 9 FT
6 - 9 FT
Always use the minimum number of
mikes necessary to cover the area.
Position the Choir Mikes
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6 to 9 feet apart.
2 to 3 feet in front of the front choir row.
2 to 3 feet above the heads of the last row.
Pointing at the last row.
2-3 FT
2-3 FT
Always Point Mikes at the Sound
Source
Like this
Mikes are more directional at
high frequencies so they exhibit
more bass off-axis.
Never like this
Keep the number of open mikes
to a minimum….
• It improves gain before feedback.
• It reduces noise and reverberation pickup.
• It minimizes comb-filtering effects.
Never use two when one will do!
The Pro Co DB-1 Direct Box
• Also known as a “DI” Box.
• The most versatile.
• Takes Instrument, Line, or Speaker Level
Inputs.
• Converts them to microphone level.
• Has a HI-CUT filter for speaker inputs.
• Has a ground-lift switch to reduce hum.
The Pro Co DB-1 Direct Box
LO-Z XLR Output
to System
Instrument or
Speaker Output
Instrument or
Speaker Input
Also known as a “DI” Box
The Pro Co DB-1 Direct Box
Ground/Lift
Switch
Hi-Cut/Flat
Switch
Speaker/Instrument
Switch
The Peavey Direct Box
• Active - requires phantom power from the
mixer.
• Has the best frequency response.
• Takes only line and instrument level inputs.
• Converts them to microphone level outputs.
• Simple to use - no switches to set.
• Peavey is the first choice unless you need
the versatile features of the Pro Co.
The Peavey EDB-1 Direct Box
DI Box
Lo-Z XLR
Output to
System
Hi-Z Input from
Instrument
Power
Light
Only two connections are needed
In-Line Transformer
Transformer
• Small and easy to use.
• Good only for instruments such as guitars.
The Shure In-Line Transformer
The Headset Monitor Adapter
Volume
Plug to monitor
speaker
Used for the
drummer
The Service Tape Machine
VU Meter
Record Level
Normally used for recording
Tape Speed
Don’t use DOLBY on Church
Recordings
You never know if the person
playing it back will have the
Dolby capability.
If you don’t use Dolby to
record then the tape is good
to play back on any machine.
Make sure the Tape Speed is
centered during recording!!
Dolby
and the Dolby is off.
Tape Speed
centered
.…or Speed Fixed
To Queue a Tape, next song….
Press Music Search >>
To Queue a Tape, repeat song….
Press Music Search <<
The CD/TAPE Unit
CD Track Select
CD Controls
Tape Controls
Normally used for playback
The CD/TAPE Unit
Output Switch to MIX position
or their will be no output from the CD!
Make sure the tape speed is
centered during recording!!
Tape Speed
and the Dolby switch is off.
Dolby
The CD/TAPE Unit
Single..Cont
• Single to play only selected track.
• Continuous to play selected track forward.
To Queue a CD Track....
3. Press Track Number (use +10 for tracks greater than 9)
4. Press Play
2. Press Queue
1. Select Single or Continuous
To Queue a Tape, next song….
Simultaneously Press….
Play
and Fast Forward
To Queue a Tape, repeat song….
Simultaneously Press….
Play
and Rewind
What is a Split-Track Tape?
• A special choir tape with voices on one
channel and accompaniment on the other.
• Using the Split-Track tape switch, you can
play back voices, accompaniment, or both.
• Generally, use both during practice sessions
and accompaniment during the performance.
Split Track Tape Switch
Selects record or playback of left only, right only, or left and
right channels.
HEADSET
RECORD
LEFT
L+R
CD-TAPE RIGHT SERVICE
RECORDER
Headset is for monitoring mixer.
This switch prevents the possibility
of a feed-back loop during record.
You can send music and voice to
the monitors with music only to
the main speakers.
• Good to help out the kids choir.
• Switch to L + R position.
• Pan mixer channel hard left or right to
select music only for the main speakers.
• Remember - choir mikes will pick up some
voice from the monitors.
The Cable Test Box
A good way to check for defective cables….
1
2
3
Never Connect Anything but
Cables to the Test Box!
I love it when
they do that.
Microphone Sales Guy
To check any 3-wire cable
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Mike cables with 3-pin XLR connectors
1/4-inch Tip Ring Sleeve (TRS) connectors
Press button #1 and light #1 comes on
Press button #2 and light #2 comes on
Press button #3 and light #3 comes on
To check any 2-wire cable
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1/4-inch Tip Sleeve (TS) connector
Press button #1 - lights #1 and #3 come on
Press button #2 - light #2 comes on
Press button #3 - lights #1 and #3 come on
Now a word about Video….
JOHN
Video System Wiring
Audio from Mixer
Audio to Mixer
TV
VCR
Switch
RF
Modulator
TV
Amp
TV
Scan
Converter
TV
Cart
Computer
Console
Stage
The Master Power Switch for the
Video Monitors….
is located in the electric closet
As a Sound Man you will
normally only operate the VCR
• Make sure the VCR/COMPUTER switch is
in the VCR position.
• Make sure the monitors are turned on and
set to channel 3.
• Push play on the VCR.
• Un-mute and adjust the VCR channel level
on the mixer for the desired volume.
We’ve made it Sound Man!
He’s finally done!