Digital File Formats

.mp3Very common – used by a range of digital recorders. Easy to handle and transcribe.
.dssThe best format for digital transcription. Used by Olympus, Grundig, Philips and Lanier. DSS files are compressed and easy to email.
.wmaWMA files are the Microsoft competitor for MP3. Smaller sized files.
.wavHighest quality option, often seen in studio recording. WAV files use up a lot of disk space and are harder to process.

Other file types include p3, au, aif, vox, VoiceIt (sri), RealAudio (ra and rm), Sony Recorder formats (msv, dvf), For The Record’s TheRecordPlayer (Court and Police Station Transcription Software), Sanyo Digital Recorder format, DSP TrueSpeech, GSM 6.10, mp2, PCM, ALaw, ADPCM, CELP and SBC. We have included lists of the usual types of digital files we can transcribe from. We also assist with others, so if you cannot see your file type below, please let us know.

Digital Audio Types

AIFC (Compressed AIFF)
CAF (Apple Core Audio Format)
DCT (Express Dictate, MSRS, etc.)
DS2 (DSS Pro)
DSS (Grundig, Olympus, Philips recorder)
DSP TrueSpeech
DVF (Sony recorder)
DVS (Royal recorder)
MSV (Sony recorder)
RA / RM (RealAudio)
WAV (Including ADPCM, aLaw, GSM 6.10,
PCM, and uLaw codecs)

Digital Video Types


If you have any questions about the file types we can assist with please contact us.

Further information about the different file types is below.

File Type – M4A

File extension: .m4a

Format type: Compressed Lossy

It is an MPEG-4 Audio file and is most often found in Apples iTunes Store as the format of song downloads because it’s smaller in size and higher quality than other audio file types. It’s often seen as the successor to the MP3 and more and more developers are including support for M4A. However it still can’t compete with MP3’s universal compatibility which is why it often needs converting into MP3.

File Type – MP3

File extension: .mp3

Format type: Compressed Lossy

MP3 is an MPEG audio layer 3 file format that uses a compression algorithm to reduce the file size. This has made it the most widely used and compatible audio file format. It is popular for all mobile audio-playing devices. Best used for audio file sharing due to its small compressed size.

File Type – MP4

File extension: .mp4

Format type: Compressed Lossy

MP4 files are commonly confused as being the newer and better version of MP3 files but this is not correct. It is an MPEG-1 layer 3 file format and unlike the MP3 file which can only store audio and MP4 file can store audio, video, still images, subtitles and text.

File Type – WAV

File extension: .wav

Format type: Uncompressed Lossless

It is a Waveform Audio file that stores waveform data and is a gold standard in studio recording. It captures and recreates an original audio waveform at the highest quality. WAV files are most commonly used in Windows systems and are usually uncompressed audio files.

File Type – WMA

File extension: .wma

Format type: Compressed Lossy

It’s a Windows-based alternative to the MP3 file format and is most commonly a lossy compression. It was created to compete with MP3 and is often used for streaming online music.

How to Convert from one File Type to Another

There are many applications on the internet that allow you to convert between different audio file formats. For a secure conversion please send us your files. Alternatively you can convert files yourself online using one of the sites below.


Which File Type is Best for the Clearest Audio?

The best one to use would be a lossless file format because the quality remains the same. Out of these five the best would be WAV as this has the best sound quality. However the files can be quite large and take up a lot of storage

Which File Type is Best for the Smallest File Size?

The best one to use would be MP3 or M4A depending on the sound quality that you want. Generally M4A has a better sound quality at a small size however MP3 is more widely used.

Which File Type is the Most Popular?

MP3 is the most popular as it is the most widely used and has a good compatibility with most digital media players. It’s become popular due to its small file size.

What is Microsoft’s preferred audio file type?

The preferred file type is WMA as it is the windows based alternative to MP3.

What is Apple’s preferred audio file type?

The best known is MP3 but Apple prefers to use ACC that Apple claims is equal if not superior to MP3s encoded at the same or a slightly higher bit rate.

What is the best file type for recording speech files

A low quality MP3 file can work fine if there is only one person in the room but generally the way you record is more important than the file type you record in.

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