Monday, August 18, 2008

EQing an amp

I've learned a bit about EQing (setting up the bass, mid and treble) an amp over the years. I've made some pretty big mistakes and learned some good tricks that I'd like to share:

Mistake #1: EQing the amp so it sounds good if I'm the only one playing.
The goal with EQing an amp is to make it sound good through a sound system in the context of a full band playing. When you're setting up your amp it's tempting to make it sound great as an individual instrument. The result will be a warm sound with a lot of bass that will sound great when you practice, but won't cut through the mix when a band is playing. This goes back to knowing your roll in the band - it's the bassist job to lay down the low end, not yours. If you're both adding bass things will get muddy fast. I don't like the tone of my tube screamer when I play by myself, but when the band is going strong it cuts right through and does it's job perfectly. I had kind of known this, but it got hammered back into my head a few weeks ago when I was EQing my amp for the new scumback speakers. I had my housemate, who's a great live sound engineer and also a bassist, give me a second pair of ears. He gave my amp less bass than I would have but I realized he was setting it for what he wants to hear coming out of a sound system so he can mix it with the rest of the band, not setting it so it sounds great on it's own. Brilliant.

Mistake #2: Not listening to what's really coming out of the speaker.
I used to do this too. I'd be standing with my head 4 feet above my amp and think to myself, "I don't hear enough highs," so I'd bend over and boost the treble. The problem with this is that guitar speakers shoot strait out like a laser. This illustrates the problem:





If you're listening from outside the "sweet spot" it's going to sound different... and most importantly it's going to sound different than what the mike is picking up right in front of the amp. When EQing the amp, make sure you're listening to the sweet spot. Either bend down and listen, or tilt the amp back so it's shooting at your ear.

The important things are that you're EQing 1) for the mike and 2) to fit into the band. Happy EQing!

2 comments:

Derek Pribnow said...

Mike, you've really hit on one of the disconnects between musicians and sound techs.

As a sound tech, I've generally let the guitarist keep their amp on stage eq'd to their preference, and then boosted and cut frequencies (sometimes quite hard) as I needed at the board. That way, everything is in their own register without needing to start a battle over amp settings that guitarists will often fight to the death over.

The problem happens when the musician listens to the live recording. They can't help but notice that it sounded different and walk away wondering what happened to the tone that they were used to hearing out of their amp.

Great explaination.

rhoy pamparo said...

i think it still starts with a good tone on the source. it also depends a lot on the guitarist's sensitivity. you don't want to boost your mids while there are vocals in the mix but might want to when soloing.

from my limited understanding, EQ on the boards should be done to put the sounds on the right registers (freq) on the whole audio bandwidth. it should not try to compensate on a lousy sounding equipment that has to be fixed on the source. BUT, i am not a "real" sound guy so what do i know! :)