Audio Recording

Essential equipment for audio recording includes:

  • microphone
  • computer (smartphone, tablet, laptop etc.) for digitising and processing microphone signals, or handheld voice recorder
  • software for recording, playback and editing audio data
  • software for converting audio data into the MP3 distribution format
  • storage device

In simple cases, all of these elements may be provided by a single package such as a smartphone. Devices such as the iPhone can be surprisingly effective at recording audio close to their speaker, or through an external microphone. They often have built-in software or free / low cost audio processing applications such as Audiboo or Tinyvox. However, these devices have relatively little free storage space which may limit the maximum recording length that can be achieved. Therefore they are most effective for short recordings and informal situations.

For most member group meetings, a more effective solution is a laptop equipped with an external microphone.  Audio can recorded very effectively using software such as Audacity (free and open source, for Windows, Mac OS and Linux). The recording files in .au format produced by Audacity are subsequently converted to MP3 format using another open source program known as LOME. Depending on the recording quality selected, Audacity may generate in excess of 1 gigabyte of data for a one hour talk, so a modern fairly high specification laptop is needed, possibly with high capacity external hard drive. As noted above, the converted MP3 file will usually be much smaller and therefore suitable for posting on a web site.

Some care is required in the choice of microphone. To create an effective recording, it's essential that the microphone be located near to the speaker. This can be achieved with a simple and inexpensive (~£10) cable attached microphone. However, many speakers are unwilling to be tethered in this manner and therefore it's worth exploring alternatives. One of these is to use a bluetooth headset (of the sort used with mobile phones) which enables shortrange wireless communication with a bluetooth-enabled laptop. This is also inexpensive (~£10) but depends on the speaker's willingness to wear the headset. [There may also be some limits on the range supported by bluetooth.]

A third option is a wireless tieclip microphone kit of the sort frequently used in conferences. This kit consists of several main components:

  • microphone plus battery operated transmitter
  • base station receiver with cable connection to laptop
  • optional cable connection to meeting room AV system

This configuration is more expensive (~£100 with a single channel base station) but still affordable. Its major advantage is that it enables the speaker to move around freely within the room and the range is usually sufficient for most rooms. The base station plus laptop must be located close to a power socket but may be at the back of the room, which is usually convenient for the volunteer operating it. Another cable is needed if the recording system is used in conjunction with a meeting room amplification system, and the base station must also be located near an AV connection socket, but the recording process is completely independent of the AV system. Multichannel base stations (~£200) are also available which can support multiple microphones, including roving hand held microphones, but require a volunteer operator to switch channels when appropriate to the recording.

Current best practice is therefore to use Audacity software with a suitable laptop and a wireless tieclip microphone kit.

Note that, although an audio recording may be used on its own, many will be used in conjunction with a slide set in PDF format. By viewing the audio recording and slideset in separate windows, it is usually possible to follow the speaker's references to text and/or diagrams within the slide set, using audio cues to determine when to move to the next slide.

A better way of publishing recordings may be to use as web hosting site such as Slideshare. This enables upload of both slides in PDF format and audio in MP3 format, and has a editing tool which enables synchronisation between slides and audio to be achieved. The conbined presentation may then be played in a manner similar to a video recording. It also provides a range of tools for tracking audience response to a presentation.

Current best practice is to publish slides and audio recordings via Slideshare.

[Other more professional recording options include the use of high quality and/or specialised microphones and recording devices, at higher cost. More detailed information on these options can be found in telemeeting-solutions wiki (not under BCS control)].