Tips, Techniques, Examples about my favorite musical instrument, the Twelve-String Guitar.

If you play guitar check out Playing Technique, or Strings / Setup. There are also some interesting posts about guitars at, you guessed it, Guitars.

If you want to spread your musical talents around, you will find some good info at Recording.

Marketing - meh - I'm probably the world's best bad example. Although you could find funny stuff there.

I've made some music videos through the years, and you can find them and other interesting music at Music I Like, Music I Play.

Saturday, January 20, 2007

Searching for the perfect 12-string microphone

I've had a few false starts and spent more money that I should have, but as of now I've settled on a matched pair of OKTAVA MC-012 with omni capsules and use them in a modified Jecklin array. I mic as close as I can get the guitar to the array baffle, so close that I sometimes hit it with the guitar!I needed microphones that will capture the sound of a 12-string. One way to audition a lot of microphones is by going to the Listening Sessions web site. They don't have any guitar with a variety of small diaphragm capsule (SDC) microphones, but there is an interesting collection of large diaphragm (LDC) microphones with guitar samples in session 5. At the bottom of the page are links to listening sessions on other sites. I like to listen to these using a double-blind method. I download all the samples, then play them in some repeatable but unknown order (I'm a programmer, so a quick perl script is all it takes),
making notes as I compare the sounds. The first thing I found is that I like the sound of Neumann microphones. Unfortunate, because they cost several thousand dollars each. Most of the really expensive microphones, like Scheops or Neumann sound better than the ones costing in the hundreds of dollars. The difference is quite obvious if you have decent monitor speakers on your computer.

Based on the listening tests, the first condensor mic I tried was an MXL1006 LDC. It sounded closest to the Neumann TL-103 in the Listening Sessions, very clear but no strident tizziness. I was never able to make this mic sound right. I didn't know that most acoustic guitar recording is done with Small Diaphragm capsule (SDC) mics because they capture more high end detail, including transients. This seemed a better fit for a 12-string. High on my double blind list were the Russian SDC microphones, MK-012 (aka MC-012), and they also got pretty good reviews from people who ran real recording studios as being particularly good for acoustic guitar. MojoPie, for one, has some good info in their review. I got 2 matched cardioid capsule mics, MC-012s, from the Sound-Room and experimented with x-y, a-b, and ortf configurations. This went on for a couple of years, concurrent with room placement experiments and treatments. Eventually it seemed that close mic'd AB, one pointed at the foot of the guitar and the other pointed at about the 7th fret gave the best sound.

My first 2 CD's were recorded with cardioid capsules, which I thought were necessary to eliminate room noise, but the Mastering Engineer of my 2nd CD (Jon at Naiant Studio) said he had to clean up some low frequency phase problems and advised omnis. I purchased matched omni caps for the MC-012's from the SoundRoom and noticed a big difference in the low end response. The low frequencies were more detailed and it was easy to localize the various sounds of the guitar. Room noise doesn't seem to be any greater a problem with omnis than with cardioid as I had feared, probably because I mic so close.

The modified Jecklin array gives better separation for the omni capsules. I separate the mics with a baffle made of a plywood, mouse pad and carpet. The mics are further apart than a strict Jecklin array and one points down towards the foot of the guitar and the other points up towards the 12th fret because I'm not interested in an accurate binaural effect as much as I am at capturing the main sources of guitar sound that I want.

A good microphone read is the FAQ page on the Home Recording microphone forum. Harvey Gerst has an excellent primer and I would have saved a lot of time and expense if I had read this carefully from the start.

Here are 2 abbreviated pieces of BWV999, 1.5 meg mp3, first of the LKSM-12 tuned down from E to C# (medium Elixir strings) and second of the Gibson B45-12 tuned to B (heavy Elixir strings).

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