What is "NetMD"?Announced in mid-2001 and first introduced on the Sony MZ-N1 portable recorder in December, NetMD is an extension to the Minidisc format that allows direct transfers of compressed, ATRAC audio from a PC to Minidisc via USB interface. Audio transfers can be conducted at rates considerably faster than realtime (up to 64x for LP4 audio on certain units).
Why is it considered a "format extension"?NetMD equipment requires complementary NetMD PC software for control and data transfer functions to be conducted. By standardizing the PC<->MD USB protocol, Sony assures compatibility between NetMD equipment and NetMD software packages from various manufacturers.
What NetMD software packages are there?Commercial
Sony also has instructions for downloading and using RealOne Player.
(Note that none of the non-commercial packages provide high-speed downloading from a PC or Mac since the secure DRM aspects of the NetMD USB protocol have not been cracked)
What equipment supports NetMD?So far:
What restrictions does NetMD impose on transfers?
What is known about the information transferred over the USB link?NetMD hacking is still in its infancy. So far, however:
The PCM is encrypted in transit because Sony is trying to prevent unauthorized access to "locked" ATRAC3 audio that may have been purchased from online music distributors; failing to encrypt the PCM data would allow hackers an easy way of making off with an "open" copy of the song.
Is there any way of transferring MP3s to MD without using OpenMG Jukebox?Dino Inglese, a Minidisc T-Station message board member offers this tip for using Simple Burner to circumvent OpenMG Jukebox (see his humorous original posting). CAVEAT: You will need Nero, and Nero's Imagedrive feature, or something similar that can create a virtual CD disc image and allow you to mount it to your desktop.
I am not an expert, but I found these first 3 steps took around 2 minutes or less for a regular size audio CD (i.e. burning and converting about 10 MP3 tracks to an audio CD 'image' on my hard drive). I have a 1GHz/PIII, so that helps with the MP3->PCM conversion times. A faster machine would mean proportionately faster MP3 conversion and image creation.
If your machine is fairly fast then Simple Burner's CD->ATRAC conversion is done in on-the-fly in RAM with the disk hardly ticking over at all.
Wouldn't the transfers go even faster with USB 2.0?Current NetMD download speeds require less than 20% of USB 1.1's 12Mbps peak bandwidth:
What other NetMD FAQs are there?
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