The Olympus WS-300M series recorders have an external microphone plug that allows for a much better audio capturing system than using the built-in microphone.

The microphone plug is a 3.5mm (1/8") "Mini" plug input. While this outlet may seem universal, (it's the same outlet that most audio headphone jacks use on consumer devices) there are several drawbacks to the mini plug jack; mainly the lack of a ground line that professional XLR jacks have.

A Note on Quality

Even with the best, or most expensive microphone, small dictation devices like the Olympus WS-300M still do not compare to the quality of high-end digital recording devices. The reasons are: the type of preamplifier built into the device that raises the audio signal from the microphone, and the type of analog-to-digital converter that interprets the sound signal into a digital file.

Audio capture is a two-step process:

1. A microphone captures a range of tones, at various polar patterns and methods (Better microphones capture a wider range of tones, and use polar patterns that help improve sound input).
2. The preamplifier/amplifier will take the sound and accurately raise the signal, then interpret them into a digital signal at a particular frequency.

Recommended Microphone 

For audio broadcasting situations, small audio dictation devices are not recommended. However, if there is no alternative, acceptable quality audio can be captured. The ideal situation is to eliminate some of the variables that cause poor quality recordings. One such option is to add a better quality microphone rather than using the built in mic on the device.

For field recording, we recommend the SP-MMC-1, a custom microphone built by SoundProfessionals.com that uses AudioTechnica microphone parts.

The SP-MMC-1 microphone's high quality, wide frequency range, directional pickup pattern and small size make it an ideal choice for a small audio recorder. While we recommend this particular microphone, various other microphones may serve as a good choice. Pay attention to:

• Frequency response (range of tones it can capture)
• Maximum sound input level
• Size, durability
• Polar pickup pattern (shape of its audio capture range, i.e. omni-directional, cardioid, shotgun, etc.)

Polar Pickup Pattern

Microphones have various polar grids that depict the three-dimensional space in which they capture audio. Omni-directional microphones, such as the ones built into the Olympus recorder, pick up audio equally from all sides. Cardioid microphones are more directional, and allow for directing the microphone toward the source of audio. Super-cardioids, and shotgun microphones are very directional, and if you are not careful you may miss audio if the microphone is not pointed exactly at the audio source. Read more about microphones here.

Dual-Mono Wiring

Some microphones will come wired for "Dual-mono." This simply means that the microphone is built with a stereo connector, but it sends the same exact audio signal to both channels equally. If you purchased a microphone that is wired for dual-mono, then you have the freedom to use either the recording settings for "Stereo", or the recording settings for "Mono". (Mono is recommended since it uses less memory.)

NOTE: Some recording devices only allow for a mono style plug. If this is the case, a stereo plug — such as the one that comes on the dual-mono wiring — will not work. If you are not sure whether your recording device will accept a stereo or mono plug, then you should purchase a microphone that is wired for standard mono (true mono). Doing this will ensure the greatest compatibility. However, if you attempt to make a stereo recording, a standard mono plug will only record to the left channel.

The Olympus WS-300M series recorder will accept a dual-mono (i.e. Stereo connector) wiring option, or a mono plug (but in stereo recordings it will record to only one channel).