Question: Other Olympus digital voice recorders have more quality modes than the DS-4000 and also record in Windows Media Audio (WMA) format. Why does the DS-4000 have only two quality modes?

The DS-4000 is designed as an Olympus Professional Dictation Device, whose primary function is to record dictation files for transcription. The two DSS quality modes – SP (Standard Play) and LP (Long Play) – are optimized for transcription. They feature a narrow frequency response and high compression; these attributes result in small files, which in turn provide the additional benefit of extended recording time.

Recordings made in the SP quality mode can be converted in DSS Player Pro for Windows to a WAVE audio format file with the properties necessary to be compatible with voice-to-text applications commonly used by transcriptionists. Recordings made in the LP quality mode may not be used by these applications; however, the trade-off is that they allow much longer recording times than are possible in the SP quality mode.

The additional quality modes available in some other digital voice recorders provide enhanced audio detail, compared with the DSS files created by the DS-4000. However, this extra detail is not necessary to faithfully reconstruct a dictation file used for transcription, and it will increase the file’s size, which in turn will restrict recording capacity. Therefore, these quality modes were not included in the DS-4000.

The DS-4000 is not recommended for recording music or interviews intended for broadcast where a broad frequency response would be desirable
Verification Source: Olympus Website