If you've ever wanted to be a dummy head for three-dimensional recording, here's your big chance. The OKM II K Classic Studio Binaural Stereo Headset microphone ($325), from German manufacturer Soundman, is one model in a series of in-ear mic pairs designed primarily for binaural recording. The headset is simple and inconspicuous and looks a lot like ear-bud stereo headphones. The mics are intended for use with compact recording devices that have ⅛-inch stereo input jacks, such as MiniDisc recorders and DATman-style devices.
The OKM II K Classic Studio mics are a computer-matched pair of tiny omnidirectional, electret-condenser elements. The capsules are embedded in molded-plastic ear buds that look like miniature yo-yos with six prongs jutting outward on each half. Although they are visually reminiscent of torture devices from the Spanish Inquisition (who expected that?), the prongs accommodate and effectively secure a set of foam screens to protect the capsules and your ears. The headset comes nestled in a black plastic case that incorporates a spooling device for the slim mic cable to safeguard against tangling and damage. An extra set of foam screens is included.
The headset includes an A3 adapter, which supplies DC power to the electret elements. The A3 purportedly offers increased dynamic range and quieter operation over directly plugging the mics in to the ⅛-inch mic jack on a portable recording device. The adapter is housed in black plastic and runs on a 6V battery. The battery is supposed to last 100 hours, and a battery check button activates an LED indicator to let you know if power is low. Features include a switchable -20 dB attenuation pad and a selectable low-cut filter.
The OKM II K headset and accessories come in a black wooden box and fit snugly into a formed plastic tray coated with a red velvety covering. The lid is lined with foam and is also dressed in red velvet, which gives the package a classy look. It also includes an owner's manual and a demo CD offering an introduction to various uses.
Testing 1, 2
I took the mics to a number of live recording gigs and conducted a few controlled tests. I don't own a MiniDisc recorder, so I made a custom cable to use the mics with a portable Sony TCD-10 Pro DAT machine and a Panasonic SV-3800 DAT machine.
For the live tests, I recorded several bands in small- to medium-size venues, with and without sound reinforcement, all with a variety of instrumentation. In addition to playing the dummy-head role, I recommend placing the mics ¼ inch apart on a flat surface to serve as boundary-layer microphones.
For the controlled tests, I binaurally recorded a drum set (from the player's perspective) and compared that with my usual technique of using overhead cardioid condensers in an XY configuration. I also recorded acoustic guitars with the OKM II K in a boundary-layer arrangement and checked out the A3 adapter's -20 dB pad and low-cut filter. Because the setup was so portable, I couldn't resist using the mics to record ambient sounds and effects while walking around too.
Listen to This
The OKM II K reproduced the original listening experience fairly well, especially when listening back on headphones. Any time I moved my head to check levels, however, the stereo image shifted. When you wear the mics while recording, think “mannequin.” The microphones captured ambient sounds quite well with minimum hassle. Although the recordings weren't on par with audiophile levels, they were quite good.
The OKM II K mics don't sound very transparent, but they have a punchy low end with good presence. The highs are a bit gritty and biting, and the upper mids sound slightly distorted. Midrange frequencies between 250 Hz and 500 Hz are lacking; although that characteristic reduces warmth, it makes some rooms sound less boxy. On sources such as baritone sax and upright bass, the mics sound a little thin. Compared with the Oktava MC012s as drum overheads, the binaural mics represent a more dramatic spatial image, but transients are less clear and the sound isn't as full. Nonetheless, the recorded results sound realistic enough.
The microphones are small and low profile. After years of toting around a loaded rack, mic stands, and a case full of microphones and accessories for stereo recordings, using the OKM II K gave me an immediate sense of emancipation. The Soundman OKM II K Classic Studio Binaural Stereo Headset microphone is an excellent low-profile option to make club recordings and to collect sounds in the field, but it's not exactly professional quality. At the price, however, the mics make an affordable and handy addition to anyone's low-pressure recording arsenal. Even when you consider its limitations, the OKM II K headset is a bargain for convenience and decent sound quality. If you need to be stealthy while recording, the mics are a fine choice.