Amplifying your Rhythm Guitar

Guys like Freddie Green and Allan Reuss routinely managed to cut through Big Bands using only an acoustic archtop guitar.

How'd they do it? - Well it helps that those bands existed in the era before amplification. Even with 9-14 horns, those bands had to play softly enough to hear Count Basie's or Jess Stacy's piano. The instruments of the day were designed to be much quieter - gut bass strings, calf skin drum heads, etc. So the question for us now is "How do we can that now?"

Today, most bassists play with amplification, often pianists have to use synthesizers, and drum kits are designed to keep pace with Marshall stacks. To balance properly, the rhythm guitarist has to be amplified as well.

The key to amplifying rhythm guitar is to keep the acoustic sound of the instrument in tact. Boomy and bass heavy sounds will muddy the sound, and moreover will be much, much more prone to feedback. The main choices are pickups or microphones. I recommend using a microphone because the sound is closest thing to sound of your actual guitar. You can use a piezo/transducer pickup if necessary, but the microphone will sound much more natural. A lot of guitar players I know who don't like to use mic, have had problems trying to use the wrong kind of mic in the wrong setting. Here are some tips on mic selection and usage:

• Mic Type - Use a hyper-cardiod, small diaphragm condenser. For those of you who have no idea what that means, hyper-cardiod, just means that the mic captures more of what it's pointed at, and less of the other stuff around it. Small Diaphragm refers to the microphone element itself, and without going into excessive detail, Small Diaphragm mics are more sensative than a Dynamic mic (ala SM57 / 58), and not as sensitive (or fragile) as a Large Diaphragm (think big studio quality vocal mics). So a mic that is sensative (but not too sensative) and pretty focused on its target (capturing less of the drummer to your left or the sax player to your right) is the right tool for Rhythm guitar.
• Internal Shockmount - Again without too much information, bascially that means the mic element is shockmounted inside the mic case, and thus it wont need one of those spider mounts to protect it from bumps. With an internally shockmounted mic you can move the mic, bump the stand, etc., without creating a really loud low boom. Your soundman and/or audience will appreciate it.
• On / Off Switch - Having an on/off switch means that you can turn the mic off when you are finding your music, or when you adjusting your mic, or changing guitars, or most importantly when you are talking to the guys on stage. How much of the between song conversation do you want the audience to hear? Also, you can minimize fedback by only having the mic on when you need it to be.
• Battery powered - All Condenser mics require power, but most PA systems already have phantom power. But for those occasions where the system does not have phantom or when you might want to use an "acoustic" guitar amp (usually these don't have phantom either), a battery-powered mic, will generally take phantom power, but use the battery when it needs to.
  
• Proper mic placement - Clearly this can be a selective thing, but I've had the best results with the same position. Point the mic down at the bridge of the guitar, and position the mic 6 inches to a foot away from the top of the guitar. You can always experiment for different stages, instrumentation, etc., but that's a good place to start. What you don't want to do is place the mic closer than 4 inches off the top, and definately pointing into one of the f-holes. The "proximity effect" (which means that at very close range mics exaggerate bass frequencies - good for full vocals, not for natural acoustic guitar) will take over less than 4 or so inches away, and the most boomy sound comes from the f-holes (where the air is pumpin out of the guitar. Also - boomy = feedback city.
• Stage setup - If posible, set up so that there are no other instruments behind you. Playing right in front of drummer will just cause the drums to bleed into your mic. Also, being right in front of the bass can be feedback inducing, because the boomy bass can bleed into the mic.
  

I personally use a RODE NT-3. It has each of attributes I mentioned and sounds superlative! When I started using it, I got compliments from the musicians I was playing with about how great it sounded. And its pretty cheap - under $200 street. I think a lot of other companies make something in the same style., though when I checked out the RODE, I stopped looking. I had given up on mic-ing my archtop guitar live, but once I found the NT-3, I knew there was only one way to go. It allowed me to stop compromising my on-stage sound.

If you absolutely must use a pickup, I recommend the K&K Archtop transducer. You could also try the Fishman bridge pickup, but I haven't tried that myself. The bottom line with pickups is that they'll never sound as good as a mic. After all, you don't listen to your guitar with your ear pressed up against the sound board.