I don't know for sure, but from the description in the torrent I think
he used something like this
MZRH10
Hi-MD™ Walkman® Portable MiniDisc Digital Music Player/Recorder
CORE SOUND STEALTHY CARDIOID MICROPHONE SET(tm)
Our Stealthy Cardioid(tm) microphones are very popular for taping concerts in very large halls, for taping at a distance, and for excluding crowd noise to the side and rear. They are not the ideal choice for taping outdoors, or in small and medium halls.
INTRODUCTION
Core Sound is pleased to offer our new Stealthy Cardioid microphones. The Stealthy Cardioids are a pair of matched miniature condensor microphones especially suited for recording situations where you are distant from the sound source, recording in a venue with an inherent bass boom, and/or want to exclude crowd noise. They are specifically designed for recording very loud concerts from the audience.
Unlike our very popular Core Sound Binaural microphones, the Stealthy Cardioids are designed to *not* have a flat frequency response. Their slightly peaked high frequency response is ideal for recording from afar, and their gentle bass frequency roll-off is perfect for audience recordings from sound reinforcement systems in large halls. Their cardioid (heart-shaped) pickup pattern works wonders at eliminating much of the crowd noise that an omnidirectional microphone can't help but record. (These same features make the Stealthy Cardioids less suitable for binaural recording or for stereo recordings when a flat frequency response is necessary -- use our Binaurals in these situations.)
The Stealthy Cardioids are provided as a matched pair and provide a level of sonic performance and stealthiness unmatched in their price range. Their transient response is clean and fast, typical of condensor microphones. They provide a very pleasing frequency balance and the ability to record tremendously loud sounds with very low levels of distortion. When combined with portable DAT and Mini-Disk recorders (e.g., Sony TCD-D8, PCM-M1 and MZ-R900) they make a very small, rugged, easy-to-use and good sounding recording setup.
Core Sound microphones are used by professional and for-pleasure tapers all over the world, including the United States, Canada, Brazil, Australia, China, Japan, Singapore, Korea, Hong Kong, New Zealand, France, Belgium, Germany, Austria, England, Scotland, Italy, Norway, Ireland, Sweden, Finland, Poland and others.
The Core Sound Stealthy Cardioids are engineered with the same extensive modifications that give the Core Sound Binaurals their ability to record extremely loud sounds without distorting.
DESCRIPTION AND MOUNTING OPTIONS
The two microphone cartridges are each mounted in their own satin-black metal shell. The shell is approximately the size of a jelly bean: roughly a quarter-inch (.6 cm) in diameter and a half-inch (1.2 cm) long. Being all metal, the microphone mounts are very durable. The black finish is heat-fused plastic and is much more durable than paint. Removable black foam, light duty windscreens are provided. Heavy duty windscreens are available.
The microphone cable enters the shell from the side. The shell can have either a fixed or a removable miniature alligator clip attached to its base. The clip can be used to attach the microphones to any convenient mounting surface, including your eyeglasses, lapels, collar, shoulder, hats, headband, lighting grids and many others. The alligator clips are finished in black and their handles are covered with a pliable black plastic. The fixed clip is permanently fastened to the microphone shell. The removable clip sits on a black nylon disk that snaps into and out of the microphone shell.
A very flexible shielded cable (designed expecially for us) exits the microphone. The cables from the two microphones join into a single cable roughly twelve inches from the microphones. The cable runs for six feet and terminates in a high reliability locking multi-pin connector; also connected to the multi-pin connector (in a "Y") is a two foot cable terminating in a gold-plated mini-stereo 1/8" (3.5mm) phone plug -- other connectors can be supplied on request. (October 4, 2002: A high quality right angle plug is now available as an option.)
If necessary, the cable can be easily split for its entire length, so that the microphones can be separated as much as 12-feet apart. This is especially useful if you use the microphones for interviews: one microphone can be mounted on the interviewer and the other on the interviewee.
The microphones are very small and unobtrusive. When the cable is routed down a shirt or sweater, there's little evidence that you are creating a very high fidelity recording of a sound event. (We strongly recommend that before you record, you obtain permission to do so.)
for more info about the mic's check here
http://www.core-sound.com/cardioid.html