This is because the input amplifier stages of the card have been overloaded. Also, recording from a source with too low a signal level, such as plugging a microphone directly into a line level in- put, will result in a very noisy recording. Good signal to noise performance can only be achieved by using a record source with sufficient signal level to register high on the VU meter. Peaks in the red zone should occur occasionally for best signal to noise ratio.
Connecting the outputs of the Antex Card to equipment designed for a similar signal level is equally important. Turning the play- back slider controls in either the Antex Mixer application or the Antex Demo application way down to compensate for connecting to equipment which should have a much lower signal level will give poor performance. These slider controls operate in the digi- tal domain and reduce the signal level without reducing the noise floor, degrading the signal to noise ratio accordingly. The trim controls on the
PLAYBACK AND RECORD DEVICES
A “device” is essentially a .WAV file on a hard drive. It can be ste- reo or mono, at one of many different sample rates or formats. Devices are not to be confused with physical outputs on the Antex card. For example, all cards in this family have dual stereo device playback capability. These means that 2 stereo files may be played back at the same time. However, the Antex sound card has only one stereo physical output. This means that the 2 de- vices are mixed together in the DSP on the card and the mixed signal is sent out the stereo output of the card. Therefore, when playing 2 devices on one card, the 2 files can only be mixed by the Play 1 and Play 2 sliders in the Antex Mixer (or other software which mimics this function). They cannot be mixed using an ex- ternal mixing board. In order to be able to mix 2 files (devices)
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