A guide to choosing and using a portable digital audio recorder, covering everything from digital dictaphones to professional field recorders. If you need a self-contained device for recording audio on location, audio note taking, or for any other scenario where recording with a computer is impractical or inconvenient, this document examines the alternatives.
In this document we look at self-contained portable digital audio recorders - the modern equivalent of the dictaphone or field tape recorder. These recorders can vary widely in cost, features and quality, and here we compare a few representative models, and give some general guidelines and comparative specifications to help you choose a machine suitable for your needs.
Many of the new generation of smart phones also offer the ability to record audio, and we'll consider their performance when compared to purpose-built devices.
- Portable recorders self-contained and powered by batteries
- Flexible usage in many differing scenarios
- Many have built-in microphone(s)
- Range of recording file formats and resolutions (WAV, MP3 etc)
- Varying methods, formats and capacities for storing and transferring audio data
- Ideally paired with good quality monitoring headphones
Who are they for?
Portable audio recorders are an excellent tool for generating podcast material, capturing interview footage, recording seminars, lectures or group sessions, and making field and location recordings of all kinds of material. There are many potential uses in education both for teachers and students, including podcasting, recording audio feedback, recording lectures, interviews or group sessions etc.
Sound quality will be dependent on the type and features of the device you use, and its price range. The most basic handheld ‘dictaphone' style machines are fine for many types of voice capture, and for audio notetaking, as are some mobile phones; midrange all-in-one recorders can capture at surprisingly high quality, and are convenient and easy to use; top quality field recorders can deliver broadcast quality audio when paired with suitable microphones.
One of the key benefits of the portable recorder is that it frees the recordist from the PC, as well as the visual and technical distractions which can accompany it, and can thus often help capture more relaxed and spontaneous performance and voice-over, delivered in varied locations. For location recording, these machines are usually quite small and discreet, and powered by batteries.
The disadvantages include their limited on-board editing and processing features, and the extra stage of the workflow (when compared to recording directly into audio software) required to transfer recordings to a PC audio workstation. They also generally have more limited storage and audio resolution - again when compared to a fixed workstation.
For many users the advantages will outweigh the limitations, and certain projects require location recording, and hopefully this guide will help to make an informed choice when picking a recording device.
Portable recorders generally share these common elements:
- Built-in Microphone and/or Microphone input(s)
- Analogue-to-Digital (AD) converters
- Storage media - built-in and/or removable
- Audio output(s) (inc. headphones)
- Data connection
In addition to these, there will be controls for the interface, and other features particular to specific devices.
Built-in microphones can be mono or stereo, and will have (like any microphone) particular pick-up pattern(s), frequency and dynamic responses, and ‘sound', all influenced by different factors in their design.
Microphone Inputs for external mics can be on a stereo TRS minijack (3.5mm) connection, as found on many consumer stereo microphones (e.g. Sony ECM range), or on separate XLR or jack connectors for each channel (L&R for left-right stereo)
The device's Digital converter is a significant factor in determining the resolution and quality of the recorded signal, converting the microphone's signal into digital audio, and will determine the sampling rate, bit depth etc of the recorded digital data stream.
The Digital file storage medium can take several forms: internal hard disc or solid-state memory, or removable media in the form of a memory card. The amount of storage space available (measured in Gb or Mb) will determine the total length of recordings which the device can hold
Audio outputs for monitoring recordings and listening to results, can be for headphones and/or line level output for plugging into an external amp and speakers. Some devices additionally have a small built-in speaker for playback.
Data interface - usually USB, although some devices (again mostly phones) have wi-fi and other wireless data transfer interface...
Accessories can include carrying case, microphone stand mount, windshield, memory card(s), USB cable, tabletop stands, external microphone(s), headphones
Most recorders offer a range of recording formats, which balance sound quality with file size.
Compressed - usually MP3. Smaller files, but some audio degradation, especially noticeable at lower bit rates (sub 128kbps). Once on computer, MP3 files can be easily tagged with ID3 metadata.
Note: Some devices (again usually phones) record to unusual audio formats such as .amr, which may not be compatible with your editing software, or easily converted to a standard format. Make sure that you choose a suitable format, or test your phone's format before using it for anything important.
Types of portable digital recorder
There follows a small selection of portable digital audio recorders, with a simple comparison of some of their specifications and features. This is by no means an exhaustive list, but hopefully is representative. Jisc Digital Media do not endorse any manufacturer or product, and no endorsement should be inferred.
Designed primarily for handheld voice recording, digital dictaphones feature built-in microphones, simple interfaces, and often extended long-play (though reduced quality) recording modes. Their emphasis on voice capture means that they are generally less suited to critical audio work, but if informal voice recording and note-taking are your main needs then they offer good value and ease of use. Note - not all dictaphones offer easy transfer of files to computer.
Olympus VN-5500PC DNS
A simple but flexible digital dictaphone and note-taker. Different quality/file size modes to suit different applications. Also includes a voice-to-text feature which claims 99% accuracy in generating text from voice recordings, though we have not had the opportunity to test this claim.