Several weeks ago I wrote about stage volume and beaming when it comes to using an amp on stage. Today I want to talk about my experiences using microphones to send the guitar sound to a PA system.
First let me start by saying that I don’t have extensive experience miking amps, and I generally don’t need to either because I either use a multi-fx pedal going straight into a PA system, or the amp itself was enough without needing to have it mic’d.
Having said that, there was a period of time when I did need to use microphones to get my guitar sound into the main speakers controlled by a PA system. I spent quite a lot of time trying to learn the best methods to do so, and after a lot of trial and error, this is what worked best for me.
The main thing that I found, as mentioned in the article I mentioned above, is that the amp has to have enough volume before being mic’d or else you’ll just be amplifying a small, weak guitar sound. The other things that I learned are 1) that you need to find the correct mic placement, 2) that you need to find the best mic angle, and 3) that you need to find the best distance of the mic from the speaker.
The placement of the microphone in front of the amp speaker is very important. The closer the mic is to the center of the speaker (the little central circle called the “dust cap”), the more harsh and trebbly the sound going to the PA will be. As you move the microphone further away from the center, it becomes darker, and as you get out toward the outer edge of the speaker (near the “surround”), the sound gets dark and muddy. The trick is to find the sweet spot for the tone you want.
To get this right, you need to get the mic plugged into the PA system you’ll be using, put it on a stand, and play your guitar with the mic in different places on the speaker. Listen to each as you play, but if you can, try to also record each position so that you can hear the difference while just sitting and listening. Once you find a place that isn’t too harsh, but also isn’t too muddy, you’ll then want to move onto….
The angle used to point the mic toward the speaker is also very important. A straight-on angle will produce a harsher sound and will send more high end treble to the PA. However, turning the microphone so that it points toward the “sweet spot” at a 45 degree angle will produce a warmer, less harsh sound. This, of course, can vary based on whether the mic is unidirectional, omnidirection, etc., but the point is that the angle of the mic can make a difference and different angles should be tried while you’re working on finding the right way to set the mic.
Some guitar players like to have the mic right up against the speaker grill. Some like to have it a couple of feet away. I found that for me, in the places I play live, I liked having the microphone a few inches away from the speaker grill. Again, this is something to play with while you’re working on getting the best sound through the mic to the PA.
Once you’ve found the right spot for the mic, it’s not a bad idea to put a piece of tape or something on the speaker grill so that you can quickly set the mic in the right placement each time you set up.
Thanks for reading about my experiences placing a microphone in front of a guitar amp, and I hope that it will provide some insight on getting a good live sound when you need to do the same.