As you have noticed, I mention leaving the EQ alone a few times.
The human brain is much more powerful than we realize.
In fact your brain will auto-correct anything you do as you apply EQ. Increase the bass and your ear will try to attenuate it. Increase the sibilance, the same will occur.
You can prove this to yourself by simply speaking into a microphone with all settings flat. Slowly, start cutting out the mids to make your voice sound like an FM radio announcer… more… more… until you sound like a huge Elvis. Then switch the EQ out. Your voice will sound awful, nasal, middy!
Now, stop talking, move the mic away… wait 5 seconds… without the mic, start speaking. Slowly bring the mic back to your lips. Listen. You’ll be amazed. I did this last night at a jam to prove it to a guitar player. He finally stopped messing with the EQ.
All of this to say, leave the EQ alone. At least for now - use it for sweetening if you must. But if you’re going to do anything dramatic, get rid of some bass using a high-pass filter. This will help eliminate low-frequency resonance without affecting the instrument’s overall tone.
Amplifier and monitor with phase reversed. (click to enlarge)
We humans are most sensitive to mid range. This is where we communicate and differentiate tonal character. Eliminating the mids may at first sound nice, but our brains will automatically try to bring it back, as our example proves.
And when you cut mids, you will invariable increase lows and highs, and then increase the level to compensate. This will only serve to cause more feedback.
Luke, close your eyes… and trust the Force!
Peter Janis is the president of Radial Engineering Ltd. He has spent years trying to figure out why most things do not work and eventually figured out that he is actually the cause.