MD-021 "codec and bitrate testing"
This disc was originally authored late in 2021 or early in 2021 to compare the differences between SP, LP2, and LP4 recording.
The disc was recording using CD-quality LPCM WAVs or high quality apple lossless files using Quicktime Player and Sync Rec on a Sony MZ-R700, which has MDLP but not Type-R or Type-S.
The NetMD tracks were written on the MD-N505 using WebMinidisc Pro to test whether or not I can hear the differences between optical and NetMD recordings. In particular, the modern NetMD software uses open source ATRAC encoding libraries, which aren't the same as Sony's original libraries as part of SonicStage.
Track Listing
- SP, Optical: All Around The World // ATC
- LP2, Optical: All Around The World // ATC
- LP2, NetMD: All Around The World // ATC
- LP4, Optical: All Around The World // ATC
- LP4, NetMD: All Around The World // ATC
- SP, Optical: Barcelona // Russell Watson
- LP2, Optical: Barcelona // Russell Watson
- LP2, NetMD: Barcelona // Russell Watson
- LP4, Optical: Barcelona // Russell Watson
- LP4, NetMD: Barcelona, Russell Watson
- SP, Optical: History Repeating // Matt Dusk
- LP2, Optical: History Repeating // Matt Dusk
- LP2, NetMD: History Repeating // Matt Dusk
- LP4, Optical: History Repeating // Matt Dusk
- LP4, NetMD: History Repeating // Matt Dusk
Conclusions
The listening for these conclusions was done on an MZ-N1, which does not have Type-S MDLP decoding.
Watch this space for further updates as I come upw ith some other tracks to test, however, it's worth noting that MiniDisc isn't (nor was it ever) an audiophile format. The format was created for convenience, customization, portability, and durability.
Improvements over the years meant that SP minidisc sound good enough for most use cases, but even an SP minidisc recorded on a Type-R machine, played back on the "best" player is not as good as CD quality. (This was possible with Hi-MD starting in 2004, however I have never seen notes about people using it this way, by then anyone who wanted to play a CD on the go had a very good portable CD audio player, and had for a decade.)
For my part, based on the files on this disc (please let me know if you recommend I try out other files, these just happened to be the highest-bitrate files I had on hand when I first made this disc in 2021-12) - Long play modes are perfectly usable. Music recorded in LP4 isn't less enjoyable than music recorded in SP, even with mid-range headphones.
The file I listened to in most detail so far (2022-05-22) was "All Around The World", and after several listens, I did notice the file gets slightly "muddier" with each further level of compression, with the open source ATRAC encoding performing slightly worse than the R700's encoder. The song is still thoroughly enjoyable even on the NetMD LP4 transfer.
Historical Perspective
(This section may need to move to a more generic page, it's interpretive based on anecdotal evidence.)
MDLP and NetMD are, on their own and individually important advancements to the format. They improve on the original goals by allowing more music at decent quality to fit on the disc and introducing/continuing flexibility like groups for things like putting multiple albums on one disc. As people started using their computers more and having more music handy, it's likely they would have wanted to either bring fewer discs with them or get more out of each disc. LP modes were used heavily on discs I got with NetMD machines in particular.
In the early 2000s, most computerized music was stored at a relatively low bit-rate. 128 kilobit MP3 was common, you might use 192 or 256k if something was special or you had intended to put it on a CD and needed it to sound nearly CD quality, even though those file formats and rates aren't really MP3 quality.
On top of all of that, Sony's own advertising spent a significant amount of time framing MDLP, Hi-MD, and ATRAC/MP3 CDs as a way to carry even more music with you. The 2004-06 Walkman catalog in Japan featured a graphic reading "My 490 favorite songs" for example.
This environment then created the moment of digital music stores that delivered music in highly compressed formats, such as the original 128k protected AAC format of the iTunes Music Store, which would allow the disk space on an iPod to go further than, say, if the files were delivered at 320 kilobit or more.