Transcribers.

Transcribers.

Transscribers

1. General provisions.

Transscriber — this is a device that allows you to significantly speed up the documentation of sound recordings obtained operationally, as well as sound recordings of meetings, negotiations, lectures, interviews, etc.

Labor productivity when documenting sound recordings using a transcriber can increase by approximately 2-3 times or more compared to working only with a conventional tape recorder.

The advantages of the transcriber are especially felt when printing texts by non-professional operators.

Since during the documentation process the operator has to return to a certain place in the recording several times for repeated listening, as well as process the recordings made in various conditions (there may be interference, noise, unclear diction of the speakers, etc.), it is of great importance that a particular transcriber model has the following functions:

• ring repeater;
• slowing down the playback speed without changing the timbre of the speaker's voice;
• text editor;
• linking text and speech;
• digital processing during listening.

According to the method of working with the original sound recordings, transcribers are divided into devices in which the original information is digitized and recorded on a “hard” disk and devices that use built-in cassette decks to play back sound recordings (such as the DOW2 equipment from DAC).

Since all the transcribers considered below use digitization of the original analog signals to implement their functionality, the parameters of the ADC-DAC path are of great importance: converter bit depth, operating frequency band, dynamic range, etc.

2. Overview of transcribers.

Comparative characteristics of the equipment considered below are given in Table 1.

2.1.Transcribers from the company “DAC”, USA.

Two models “DOW1” and “DOW2” are presented. Both devices belong to the category of autonomous portable devices with built-in power supplies.

“DOW1” compact device that combines a digital tape recorder and means for cleaning records. Easy to operate. All controls and indicators are located on the front panel. In addition, there is a foot pedal that duplicates some of the main controls of the digital tape recorder. To operate, you need to rewrite the original soundtrack to the internal “hard” disk. The disk capacity allows you to store 79 minutes of recording. It is possible to connect an external disk.

The device contains a TMS320C25-36 MHz control processor and a DSP56200 processing processor, which makes it possible to implement an adaptive filter with 256 coefficients, a 26th order low-pass filter, and a high-pass filter with a cutoff frequency of 200 Hz and a slope of 24 dB/oct.

To display information about the recording being played, a 5-digit seven-segment LED indicator is used, showing the time in minutes and seconds.

To quickly find the desired place in the recording, there is a scanning mode that allows playback with 4x acceleration, although with deterioration in intelligibility.

The advantages of this equipment include ease of use and the presence of fairly powerful digital processing tools that allow cleaning up noisy recordings without the need for additional equipment.

Table 1.

“+” — yes; “-” — no; s.b.PEVM — system unit of the PC; n/a — no data

* — determined by the type of the installed sound card;

** — selected by the user depending on the required recording time.

*** — the sampling frequency can be adjusted in the range of 5.512-48.0 kHz.

The main drawback is the lack of a built-in text editor, which requires either a computer or a typewriter for normal operation.

“DOW2” is similar in functionality to “DOW1”. It uses a built-in two-speed stereo cassette deck to play back original recordings. To organize the ring repeater mode, the equipment has a buffer memory that allows you to store up to 60 seconds of audio information.

In “DOW2” There are 3 foot pedals that duplicate some of the controls of the cassette deck. It is possible to set the pedal modes using internal switches. The following modes can be set:

• REWIND(rewind) — PLAY(playback) — FAST FORWARD(fast forward);
• REVIEW(review) — PLAY(playback) — CUE(pause);

REVIEW(review) — PLAY(playback) — LOOP(ring).

The equipment has a ROLLBACK mode, when the PLAY button is pressed and held, the recording is returned for 1.2 or 3 seconds, depending on the position of the switches on the rear panel of the device.

The “DOW2” has more powerful recording cleaning tools than the “DOW1”:

• 500th order adaptive filter;
• a filter for suppressing low-frequency noise that occurs when recording signals in the room (the “rumbl” filter);
• a filter for suppressing high-frequency noise from the magnetic tape (the “hiss” filter).

2.2. Transcribers of the company «CRT», Russia.

The company's products are represented by the products «Caesar», «Caesar — T», «Caesar — SB», which are computer transcribers.

These devices are identical in their functional characteristics and differ only in their technical characteristics. The Caesar transcriber uses the STC-H141 Centaur sound card developed by CRT, the Caesar-T uses the STC-H126 with a telephone interface, and the Caesar SB can use any standard sound card compatible with the Sound Blaster standard.

The Caesar series transcribers have been developed specifically for the needs of office services that have large volumes of work on documenting audio recording texts.

The software supports both the functions of a text editor and a digital tape recorder.

A distinctive feature of the Caesar series transcribers is the ability to compare the typed text and the corresponding sound. The connection between text and speech is established automatically and allows you to instantly find and listen to the corresponding sound fragments of the speech signal in the typed text when you move the cursor to an arbitrary section of the text.

The undoubted advantage of the Caesar series transcribers is the convenient and simple software interface and relatively low cost.

2.3. Automated system for operational documentation of oral presentations “Allegro” by the CRT company.

This system is designed to receive texts of speeches at conferences, meetings, congresses, symposiums and is a local network of computer transcribers

“Allegro” allows:

• to perform operational (in real time) documentation of a meeting, serviced by a team of an editor — administrator and 3-5 typists;
• to completely abandon the services of stenographers, replacing them with qualified typists;
• receive a printed text of a speech literally a few minutes after its completion;
• instantly compare the text of the speech protocol with the corresponding fragment of the recording.

The Allegro system is built on the basis of IBM compatible personal computers and can function in the Microsoft Windows for Workgroups or Windows 95 environment.

The basis of the system is sound server, which provides high-quality input/output of sound signals to the computer, their recording in memory and transmission of fragments of the recording to the workstations of the editor-administrator and typists.

The editor-administrator controls the process of sound recording, the state of the processing process at the workstations of typists, the creation of the final document and compares it with the original speech, controls the process of printing the document on the printer.

Typists receive a fragment of the recording from the sound server, listen to it and type the text by ear.