Instruction manual guidePORT 3200 system

Planning the content
6-20
Note:
If the audio information for a certain category is missing in a certain
location, you have to redirect the audio information from another
category to it (see “Redirecting the audio information of all Storage
Events from one category to another category” on page 8-33). If not,
the visitor with a receiver set to this category will not hear any audio
information at all in that location.
Creating a list of all Storage Events
You require a list of all Storage Events. On it, the exhibits must be sorted
according to the locations in which they are to be presented.
Recording informational texts and setting the audio quality
For every exhibit there must be an informational text read out by a
professional speaker, mixed and recorded on a CD or hard disk in a
recording studio if possible.
Characteristics of the audio files In order for your Events to have optimum sound quality when they reach
the visitor, you should create the audio files in high quality. High quality is
achieved with the help of excellent microphones, high-quality recording
equipment and a file format with a high sampling rate (we recommend
44.1 or 48 kHz). You can record in mono or in stereo as you wish.
In order that the INM software can process the audio files, it is vital that the
audio files have the following two characteristics:
! File format: Windows Wave (.wav)
If you want to use recordings from a conventional audio
CD (file extension .cda), you will have to convert them to
the Windows WAV format using suitable sound
processing software.
! Resolution: 16 bits per sample
The INM cannot process higher or lower resolutions.
How should the audio files be
compressed?
The INM software compresses the WAV files (.wav) automatically as soon
as you assign them to a Storage Event. The Ogg Vorbis format (.ogg) is
used to compress WAV files in stereo (for licensing information see
page 18-2) and Sennheiser's own compression method is used for WAV
files in mono. Both methods guarantee excellent sound quality with
minimum strain on the memory.
When you assign an audio file to an Event using the INM software, you can
choose between the following compression levels, which differ in the
number of channels (mono or stereo) and in the sampling rate (16 to 48
kHz) used:
A sampling rate of 16 kHz is sufficient for speech. If you additionally want
to use music or sound effects, you should select a higher sampling rate.
The following diagram compares the sampling rates of the usual audio
Channels
Sampling rate
(kHz)
Suitable for Designation in the INM
1 (Mono) 16 Speech Speech mono (low)
2 (Stereo) 16 Speech Speech stereo (low)
2 (Stereo) 32 Music Music stereo (middle)
2 (Stereo) 48 Music Music stereo (high)