Toshiba Type F / OB-1056A

Output Impedance - 600 ohms

Bass cut implemented by moving a mechanical baffle.

The following is translated from the Japanese data sheet for the Toshiba Type F:

Applications: F-type velocity microphones are widely used for public address systems in various halls, theaters, conference rooms, and assembly halls.

Features: This compact, highly sensitive mid-range velocity microphone features a continuously variable acoustic tone control, allowing you to fine-tune the tone to your liking. Our proprietary reinforced ribbon ensures even longer life. Its bidirectional design also avoids noise and harmful wall reflections, preventing feedback and producing a beautiful tone.

With an F-type velocity microphone, the side without the cord is the front, but because it is bidirectional, the rear has almost the same characteristics. Virtually insensitive to sound from the sides. When a velocity microphone is used too close, the proximity effect increases sensitivity to low frequencies, reducing intelligibility. In such cases, turn the knob on the bottom of the microphone toward H. Also, keep the microphone in the "H" position if frequent handling is expected, or if it will be transported or stored for an extended period of time. If you want to emphasize the low frequencies in particular, turn the knob toward L. The internal wiring is as shown below; we recommend using a balanced configuration.

Please note the following points to ensure long-term use of the microphone.

1. Do not use in extremely strong winds. Also, please open and close the storage box as quietly as possible.

2. The microphone uses a strong magnet, so it is not suitable for use in places with a lot of iron powder. It is safer to avoid bringing watches and other items close to it.

3. Do not apply a tester to the microphone terminals or pass any current through them.

4. Store in a dry place.

5. Remove the seal and bring the product to us or Aoshiba Shoji for repairs without opening the product.

A description of the Toshiba F ribbon microphone at Soviet American Audio