Thursday, February 16, 2012

Audio-Technica AT4050ST Stereo Studio Condenser Microphone

A nekkid AT4050ST

With a list price of $1,625 and a street price of $1,299, in this economy, you have to remind yourself that this is a stereo condenser side-address mic with two separate capsules under the grille; a cardioid and a figure of eight. Well, you can sort of see that in the picture on the left.

The AT4050ST came out in September 2009 along with three or four other significant A-T mics. In the land of microphone manufacturers, Audio-Technica is a giant. They make so many microphones that when they decide to release three or four at the same time it’s easy to lose track of them. The AT4050ST is part of Audio-Technica’s top of the line 40 Series. In that line alone there are about fifteen different microphones. 

The AT4050ST is a clever repurposing of existing AT4050 transformerless technology. They already have the BP4025 X/Y stereo field recording mic that has a fixed-position pair of one-sided large diaphragm capsule mounted in one head grille. Why not take it a step or two further? How about a 90 degree X/Y, a wider 127 degree X/Y and a discrete Mid/Side array, all in one mic? Your choice via a three-way switch. Add a 10 dB pad and an 80 Hz high pass filter and you have the AT4050ST.  

The dual membraned AT4050ST capsules are externally polarized requiring 48V DC phantom power capable of 6.4 mA. Each 50 ohm capsule is separately powered. The grille is very transparent, reducing internal reflections. The mic uses a five-pin XLRM connector and a 16-foot, 8-conductor, shielded cable with two 3-pin XLRM-type connectors at output end is provided as is the AT8449 shock mount for 5/8"-27 threaded stands. 

Two Can Be Better Than One
In case the implications are not apparent. Having two capsules mounted in the same head grille means more solid stereo imaging, especially if your audio will ever be heard in mono. And trust me, it will. FM radios “blend” the stereo to mono when reception becomes challenging. Clock radios, elevators, in-store overhead systems, message on hold and other audio playback system are mono. 

A stereo mic gets high points for practicality. One mic, one cable, one mic stand; done. Drum overheads, individual acoustic instruments, even amps can be stereo miced. Drum overheads is a no-brainer, but which of the three arrays to use might cause you to think a bit. If you can’t figure out which to use, go with the Mid/Side array recording the front-facing cardioid and side-mounted figure of eight to separate tracks. Record the figure of eight to two tracks. Then, before mixing, hit the polarity switch on one of them, pan each full left and full right and subgroup them. Start with the front-facing cardioid. As you bring up the figure of eight tracks the spread will widen. 

Wide or W i d e r
If you start with the wide 127 degree array and find a hole in the middle, either pull the mic back some or switch to the 90 degree array. You can also just reduce pan during mixing to pull the edges back in. There may be some cancellation due to the overlapping, but it may be inaudible or non life-threatening.

Stereo micing solo instruments can also improve your sound. While setting up a typical left/right recording of an acoustic guitar, I found the 127 degree array provided a very wide stereo image. But don’t stop there. If you’re micing acoustic double bass, remember, there are sounds coming from both the upper and lower bouts, even the fingerboard. Instead of left/right, position the mic so it get the top and bottom of the bass. Because the sound of a clarinet and sax comes from the bell and the body, you can do the same thing there to get the whole instrument.

Sure, it’s a stereo mic, but you don’t always have to use it in stereo. The figure of eight is my favorite singer/songwriter pattern for vocals. For those who can play and sing at the same time. Here’s a way to mic both voice and guitar separately and still get enough isolation to work with each track separately.

Orient the figure of eight so it’s horizontal to the ground; sideways, if you will. Slide the mic into place for vocals while someone is singing and playing acoustic guitar. Listening with headphones, twist the mic in the suspension mount until the acoustic guitar is in the null of the figure of eight. Then, put a hypercardioid on the guitar and aim it so the singer’s voice is off the back. Record to separate tracks. Notice the amount of separation you get.

Or, even more simply, try either of the AT4050ST X/Y patterns, but as with the bass and wind instruments, position the mic to go up and down instead of left and right. Aim one lobe at the mouth and let the lower lobe pickup the guitar. When I tried it, I liked the 90 degree array best. Your mileage may vary. The AT4050ST also works really well on any stereo amps with chorusing or other stereo effects.

But wait, there’s more!
If you’re into nature recording, the AT4050ST will probably need some wind protection, but whether it’s a busy cityscape, rolling ocean waves at the beach, crickets around a campfire or a summer rain the results will be well worth it. 

So two mics and a Mid/Side matrix for $1300. If you’re used to spending $150 to $399 for mics, this may seem like a lot, but the AT4050ST is a very solid microphone. I’m thinking it’ll be an upgrade from where you’re at and a very versatile one at that. 

Ty Ford may be reached at