Available Sound Properties; Design Guidelines; Motomixer - Motorola E398 User Manual

Technical Specifications for MP3:
Bit Rate: 65kbps max
Recommended File Size: 75k
Maximum Duration (NW dependent): 16-30 secs

Available Sound Properties

The following table describes the available MP3 encoding properties on the E398
Platform.
File
Type
MP3 24kHz
MP3 16kHz
*Overall bit-rate cannot exceed 64 kbps.

Design Guidelines

Since ring tones need to be at a consistent audible level, compressing the original content
to reduce the peak-to-average ratio is necessary. After the audio is compressed it is
advisable to re-normalize the audio to 0db before saving the compressed MP3 file.
Note: Ring tones are generally between 15-20 seconds in length. Based on the
recommended bit rates that would yield a file size between 75-150K per tone. It is
advisable to keep file size beneath 100K to allow the end-user to download multiple tones,
but there is no file size limit except for total free memory available on the device.

MotoMixer

The Motorola MotoMixer feature allows users to mix a repeating "base track" directly on
the Motorola E398 using the MotoMixer application. The base track consists of four parts:
three content-specified instruments and a drum. Four variations are provided for each part
in the base track file. Selecting one of the four variations for each of the parts at a specific
point in time creates the mix. The mix created by the user can be saved in a file referred
to as the "mix file" and can be recalled later to be used as a ringtone or sent to another
mobile phone using SMS or email. The initial release of the Motorola E398 will not support
mobile originated messages containing MIDI files.
24
Sampling Bit
Frequency Depth
16
16
Bit-rate
Mono/Stereo (kbps)
Stereo
Stereo
40
40