There may be those wondering what record mode to use and when. I'm only covering the modes I'm familiar with, there are others on Net MD and HiMD devices.
Mode Description:
Stereo:
Stereo is the standard recording mode for Minidisc. Stereo uses ATRAC compression to record two separate channels on the disc. In this mode the record time is indicated on the disc package plus an additional 59 seconds. A 74 minute disc is 74:59 and an 80 Minute disc is 80:59. This mode is compatible with all Minidisc players and recorders.
Mono:
Mono is another standard recording mode for minidisc. Mono uses ATRAC compression to record a single audio channel on the disc. Recorders will mix Left and Right channel information together to form a mono track. In this mode, record time is twice that of stereo as only half of the information is recorded.
LP2:
The LP2 mode is the high quality MDLP mode. LP2 uses ATRAC3 compression to record two separate channels on the disc. In this mode record time is double that of Stereo due to the enhanced compression. Recordings in this mode will play back as silence on non MDLP equipment, however track titling will still be available.
LP4:
The LP4 mode is the low quality MDLP mode. LP4 uses ATRAC3 compression to record a single audio channel PLUS a highly compressed stream of stereo difference information. This joint stereo mode does not provide full stereo separation. Users are likely to notice quality issues with this recording mode. In this mode record time will be four times that of Stereo mode due to the enhanced compression and the use of joint stereo. Recordings in this mode will play back as silence on non MDLP equipment, however titling will still be available.
Mode selection for recording music:
Stereo: Stereo Mode should be selected if the source program or programs are stereo (real or duophonic) AND the source program will fit within the recording time of the disc, AND the highest possible quality is desired, This mode should also be selected if compatibility is required for non MDLP decks. If changing modes is a hassle and the amount of Mono content is minimal it may be desirable to record both stereo and mono content in this mode. Examples include the Beatles Red Album. If both stereo and mono content to be placed on the same disc (such as a stereo LP album and a Mono Album) the stereo content should follow guidelines on recording stereo content, and the mono content should follow guidelines for mono content.
Mono: Mono mode should be selected if the source program or programs are Mono and will fit in the recording time available. Mono mode is also acceptable to provide maximum compatibility. Downmixing stereo content to mono to allow for more capacity on non MDLP equipment is also acceptable IF the stereo content is true stereo and NOT duophonic. Duophonic content should not be recorded in Mono. If both stereo and mono content to be placed on the same disc (such as a stereo LP album and a Mono Album) the stereo content should follow guidelines on recording stereo content, and the mono content should follow guidelines for mono content.
LP2: LP2 mode should be selected if the source program or programs are stereo (real or duophonic) and the user requires (or desires) the ability to fit more content on the disc. The user must be sure that all playback equipment to be used is MDLP capable. This mode ideally should only be used for stereo content as LP2 recording time is the same as Mono. If both stereo and mono content to be placed on the same disc (such as a stereo album and a Mono Album) the stereo content should follow guidelines on recording stereo content, and the mono content should follow guidelines for mono content.
LP4: LP4 mode should be avoided when possible for music recording. The quality is similar to or less than 128 kbps MP3. If such recording time is necessary, this mode can be used for stereo content and for mono content. Due to separation considerations, the user is advised to either test or avoid this mode for duophonic content. Again, it is only suggested to use this mode if the user finds the quality acceptable for purpose. If both stereo and mono content to be placed on the same disc (such as a stereo LP album and a Mono Album) the stereo content should follow guidelines on recording stereo content, and the mono content should follow guidelines for mono content.
Voice recording:
Stereo: Stereo mode should be selected if stereo separation in the voice content is required along with compatibility with non MDLP equipment. Since most voice recordings are suitable in mono, this mode is likely not required. The recording quality of this mode greatly exceeds what is needed for standard voice recording.
Mono: Mono is the best mode for voice content if stereo separation is not required and compatibility with non MDLP equipment is desired. The recording quality of this mode greatly exceeds what is needed for standard voice recording.
LP2: LP2 should be selected if playback on an MDLP device is desired and full stereo separation is desired. The recording quality of this mode greatly exceeds what is needed for standard voice recording.
LP4: LP4 should be selected if non MDLP compatibility is not required and full stereo separation is not required. This is the ideal mode for most voice recording applications when playback on MDLP equipment is possible. The recording quality of this mode greatly exceeds what is needed for standard voice recording.