Samson DA-5L Manual page 22

About dbx
and Tone Squelch
About dbx® Noise Reduction:
All the components in the Samson UHF Synth System utilize dbx® noise
reduction so as to ensure the highest fidelity sound with an absolute
minimum of background noise and hiss. dbx® is a companding system;
that is, the signal being transmitted has its dynamic range compressed
and its high frequencies boosted (this process is known as pre-emphasis
encoding), and the signal being received has its dynamic range expand-
ed and high frequencies attenuated in an exactly opposite way (this
process is known as de-emphasis decoding). The pre-emphasis
encoding process is automatically carried out by the UT-5 and UH-5
transmitters and the de-emphasis decoding process is automatically
carried out by the UR-5 and UR-5D receivers. For this reason, you must
use these matched components in order for the noise reduction to work
as intended.
Note also that the headroom available from using the dbx noise
reduction system typically exceeds the peak limit of the UR-5 and UR-5D
Audio Level meter by approximately 20 dB. Therefore, you should
experiment (by listening or other method) in order to find the proper
signal level. In many cases, the meter will be well beyond its peaked or
pinned reading without incurring any distortion of signal.
About Tone Squelch:
The Samson UHF Synth System also provides an automatic tone
squelch feature that effectively prevents the UR-5 and UR-5D receivers
from passing unwanted audio signal generated by outside sources.
Here's how it works: Both the UT-5 and UH-5 transmitters add a super-
sonic 38.4 kHz tone to all audio signals they transmit. The UR-5 and
UR-5D receivers will refuse to pass through any received audio signal
that does not contain this tone (for example, radio conversation between
passing taxicab drivers).
Noise Reduction
®
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