Monday, October 27, 2008

Where to Place the Microphone when Recording Acoustic Guitars

As Mike said in the previous post, things have been a little hairy on this side, so I must apologise for the lack of new content over the last few weeks. With the formalities out of the way, let's get started with the good stuff...

When recording acoustic guitars, it is typically best to use a microphone rather than its built in pickup. The reason for this is that an acoustic guitar is known for its acoustic sound (i.e. the "natural" sound it makes in a room) rather than for the electronically reproduced sound its pickup would create. However, the quality of the recording is also highly dependent on the quality of the mic. So, this leaves you with two options: either buy a decent mic (preferably a condenser mic), or use the built-in pickup if it sounds better than your cheap mic.

Okay, so I've now convinced you to get a decent mic, and you probably think that it makes no difference where the mic is placed, as long as it's fairly close to the guitar. Well, that's simply not true, your mic placement is extremely important. Let me explain...

If you place the mic far from the guitar you will get more of a room sound than a defined guitar sound. In other words, your guitar track will sound quite spacious, as if there was a reverb effect on it. On the other hand, if you place your mic close to the guitar, you will get more guitar sound than room sound. This seems pretty obvious, and it is... but sometimes it's good to hear the basics. I can see you're a bit disappointed, so let's go a little deeper...

If you place your mic close to the bridge, you will get a very twangy sound (i.e. loud mid to high frequencies with little bass) and you will also hear the pick hitting the strings. However, if you place the mic close to the bottom of the neck, you will get a bassier/warmer sound. The reason for this is that the strings have more room to move on here than they would at the bridge, meaning that the higher frequencies of the note are produced where the string is tight and the lower frequencies are produced where the strings are loose. You may not want to place your mic right by the sound hole because it is typically too bassy and loud there, so your mic will start clipping.

You can see from the pictures below, that I like to place my mic by the bottom of the bridge, but aimed towards my strumming hand. By placing my mic here, I will get a warm mix (meaning a mix with a fair amount of bass but still with a defined mid and high tone). By aiming the mic towards the strumming hand, the sound of the pick hitting the strings will become clearer, which most artists consider to be a good thing because it adds definition. The nice thing about this setup is that if you want to remove bass later, it is simple to add a high-pass filter in Ardour (or any other DAW) to get a thinner and clearer mix.

I have recorded the sound of the guitar whilst moving the mic from the nut to the bridge and whilst moving closer to and further away from the guitar. Once you hear this, you will understand completely what I've been trying to get down in writing. The MP3 is available from the link below:

AcousticMicing.MP3 (1,619 kB)

Other posts you might find interesting:
What Gives a Guitar its Tone?
Microphone Review: Shure's SM57
Sound Proofing and Room Acoustic Basics
Sound Mixing Tips: EQ vs Volume
Stereo Panning Tips: Panning for Gold


robvp said...

Hi Brian,

I really appreciate all the work you do for the `open source recording fanatics'! Thanks very, very much!

Commenting on this article I would like to add some experience I had when recording classical guitar. I am not a pro, not as player nor as recording `engineer' but perhaps this helps other musicians.

My best recording so far (in my humble opinion) came from aiming just slightly above the sound hole at about 30 to 40cm from the guitar at a 45 degree angle. This way I pick up some noise of the fingers (which I think do add to a recording because live you cannot escape it so why hide it in a recording?). Then again it really depends on which guitar you are recording.

My concert guitar needed another approach as the cheaper ones so I guess it's a matter of try and failure. I have posted my recording here;

(just added a very slight reverb to the original recording)

I use a Studio Projects B1 mic which is much better then the Samson C01 I used before and it comes for a very reasonable price.

Thanks a lot for all your work! Much appreciated by this linux and music lover!


Brian the Lion said...

Hey Rob,

Thanks for the awesome feedback and encouragement. It's great to hear that what I write is useful.

I certainly agree with your ideas of recording the finger/pick sound, because it sounds more natural and for an acoustic guitar that is exactly what you want. Although, it's nice to know what affects the overall sound for those times when you feel like being creative or experimental.

Thanks again.

nalmeth said...

I'd like to second Rob's comments. I really appreciate your posts and the effort you put in to make them.

I just eat up this type of thing, and I must say its very refreshing to see not only linux-specific studio content, but just generally the experience you share with us.

Oh, and the Hydrogen templates - fantastic idea!
It's great how you're post actual media. It makes the information much more useful.

The community needs more of what you do, my friend! Please keep it up!

Brian the Lion said...

Hey Nalmeth,

Wow, what a compliment! Thanks so much, I really appreciate it. It's really fantastic to know, that the stuff I do makes a difference.


Noel said...

I'd like to add my own thanks for all you do. Also, I wanted to tell you that I used this mic technique last weekend while recording some acoustic guitar tracks. I set up the mic as you suggested, and also simultaneously recorded another track using my acoustic's onboard pickup. I then doubled the guitar part using exactly the same technique, panned the two pairs of tracks slightly left and right, applied some EQ (slightly different for each of the track pairs to give them a little separation), and ended up with what I think is a beautiful, lush, acoustic guitar sound for the song. I'm VERY pleased with how it turned out.

Thanks again!

Brian the Lion said...

Hey Noel,

Thanks for the excellent feedback. That sounds like a good idea, could you maybe post a link up of your acoustic guitar sound?


Noel said...

Sure. You can find a brief sample here. This is audio is unmastered and undoctored except for the EQ I had on the tracks. I simply muted the other instruments, exported this bit of audio, and normalized it in ReZound to get the volume up a bit. I'd post the whole song but it's not ready yet. As always, I'm struggling with lyrics... :-)

Brian the Lion said...

Thanks Noel