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 • 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.
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…. • 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
It All Starts Here… DI Box Mixer
The Big Picture Peavey AUX-2 Fold-back Speaker 70 Volt Amp Class Speakers 70 Volt Amp Bogen From Signal Sources Mixer Main Speakers EQ CONTROLLER MAIN Peavey Tannoy Tannoy Stereo Amp AUX-1 Monitor Speakers EQ Peavey Yamaha Mackie Peavey
Class Speakers actually consist of... • 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!
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 Head Room Normal Signal Level Noise Time
Clipping Causes Distortion….. Clipping Clip Normal Signal Level Noise Time
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…. Back down from clipping and hope for the best. TRIM? Or…..
The MACKIE Waysets 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.
The Graph you’ll see on the video…. Volume 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.