Must Read Before the School Festival! PA Course for a Successful Live!

This blog is a must read for all of you who are preparing for a school festival or event!
I would like to tell you why some events and live performances are far from what is considered to be a top-notch sound.
I will explain with examples so that you can easily understand what I mean.

No.1The sound coming out of the PA speakers is not consistent

When you connect drums, guitar, bass, vocals, etc. to a mixer and play the sound out of the PA speakers, you may have heard something like, “Hmmm......... the guitar is kind of loud, but I can't hear the bass drum at all,” or “The vocals are fine, but when the instruments are added, I can't hear the vocals at all. You may have some familiarity with this phenomenon.

This is not surprising, since the loudness and dynamic range of each sound is different.
Yet, many people are struggling to match the level of the sound by fiddling with the faders while the band is playing.
To put it bluntly, “That's impossible!"

There is a simple device that solves this problem.
It is a compressor/limiter.

dbx / 266xs Stereo Compressor

Classic Pro / CPCLII Stereo Compressor/Limiter

Connect this to the send return of the mixer you are using.
That's all you need to do.
Once the compressor is connected to the aux of the mixer, the amount of signal sent to the aux (comp) of each channel should be determined for each instrument.
For example, a channel with a loud percussion sound should send a little more signal to the comp, while a channel with a sustained sound with little volume variation should send almost no signal at all.

Many people think that compressors work by compressing.
This is not incorrect, but if you know the principle of operation, you will realize that it is not compression.
Since it also amplifies the input sound, when used in a mixer, it reduces the variation in volume among instruments and produces a well-balanced sound that is very easy to listen to.
It also has a limiting element, which is a very nice bonus that prevents damage to speakers caused by excessive output.

No.2No Powerful Low Sound

This is common in college student clubs.
You want the bass drum sound to be strong, but it doesn't happen.
After a lot of tinkering, the PA speakers go all weird (and the sound is lame).
This is impossible unless you use a bi-amp system.
You can't just connect the signal from the mixer to the power amp and then connect it directly to the PA speakers, no matter how much you tweak the EQ on the mixer!
The reason is that the woofer speakers have midrange components mixed in.
Use a channel divider to separate the bass from the signal from the mixer, connect it to the power amp, and then connect it to the speakers. Then you get a sound like a top-notch live music club.

BEHRINGER / CX2310 V2

dbx / 223xs Crossover (Channel Divider)

ART / CX311 Channel Divider

However, the speakers must be bi-amped or a speaker system dedicated to bass must be provided.
In addition, a power amplifier for it is also necessary.

No.3Microphones Feedback

The most effective is graphic EQ.

BEHRINGER / FBQ6200HD

dbx / 231s Graphic Equalizer

BEHRINGER / FBQ3102HD

ART / EQ351 31-band Graphic Equalizer

A 31-band stereo type is better for PA use, but 31-band mono is also acceptable if it is to be used specifically for vocals.

The reason for 31 bands is that feedback is similar to the resonance of a very narrow band of sound.
Reduce the level of only that narrow bandwidth.
If you reduce the level of only that part, the overall sound quality will not be affected.
If the level is lowered to 10 bands or so, even if the level of the howling band is lowered, the nearby bands will also be lowered, making the sound completely unusable.

No.4Choose the Sound You Want to Get Out of Your PA Speakers

If you only have a small, low-channel mixer, not all sound has to go into the mixer.
If you go by priority, first place is vocals, second is drums, and third is bass.
Vocals can only be heard through a PA. Drums are instruments whose volume cannot be adjusted.
Bass can adjust the volume with an amplifier, but it is necessary to spread the sound throughout the band's ensemble.
Guitars and keyboards should be loud enough if the amplifiers are well connected.

I think it would be useful to know this much.
Good luck with the school festival.

Next time, I'll continue with “Creating an Active Servo DC Supply” that I'm in the process of making!
Please look forward to it.