In article
(Scott Soderlund) writes:
Hi,
I recently started working on a project where the computer captures
samples of someones's speech. Each of these samples is run through a
noise gate to improve the quality of the sample. I've done a lot of
reading to figure out how noise gates work and have pretty much come
up with that they help to lower the perceived background noise. Is
this correct? In my case, I've got a checkbox that is checked to
start running the samples through the noise gate. There is also a
slider bar that adjusts the threshold from 0 to 100. The comments
I've found inside the program indicate that the "0 to 100" is supposed
to represent the percentage of total signal strength. Is this likely
correct? What does this mean? I understand that when I change the
threshold that everything above the threshold is supposed to get
louder, but how does this relate to the total signal strength (and the
threshold being somewhere in between 0 and 100)?

Thanks in advance for any advice!

Scott

A noise gate works by sensing the signal amplitude and comparing it with a
threshold value: if the signal exceeds the threshold, it is passed through; if
it drops below the threshold it is not passed. This has the effect of turning
off low-level sounds, like background noise, as long as they are quieter than
the threshold level. Signals above the threshold don't get louder (unless the
gate also adds gain), but signals softer get turned off.

There are many approaches to gating and some are more complicated in terms of
the time course of the signal switching on and off and the amount of
attenuation below the threshold, but they all do essentially the same thing.

-Jay
--
x------- Jay Kadis ------- x---- Jay's Attic Studio ----x
x Lecturer, Audio Engineer x Dexter Records x
x CCRMA, Stanford University x http://www.offbeats.com/ x
x-------- http://ccrma-www.stanford.edu/~jay/ ----------x

Scott Soderlund wrote:
Hi,
I recently started working on a project where the computer captures
samples of someones's speech. Each of these samples is run through a
noise gate to improve the quality of the sample. I've done a lot of
reading to figure out how noise gates work and have pretty much come
up with that they help to lower the perceived background noise. Is
this correct? In my case, I've got a checkbox that is checked to
start running the samples through the noise gate. There is also a
slider bar that adjusts the threshold from 0 to 100. The comments
I've found inside the program indicate that the "0 to 100" is supposed
to represent the percentage of total signal strength. Is this likely
correct? What does this mean? I understand that when I change the
threshold that everything above the threshold is supposed to get
louder, but how does this relate to the total signal strength (and the
threshold being somewhere in between 0 and 100)?

Thanks in advance for any advice!

Scott

In layman's terms: If a sound is "35" or louder (35 being an arbitrary
number, which would usually be in dB anyway, no?), the signal passes through
with no change. If the level is quieter than "35", the gate closes and no
sound passes through. Ergo, when someone is talking, the gate is open and
nothing's different to the original recording; when they stop talking and
all you can hear is the background noise, the gate closes and you hear
silence.

--
TJ Hertz
http://www.whatyourenot.com

"David B. Thomas" wrote in message
...
....ice thing about ....oise gates is ....emove noise without
...urbing the sound quality.

LOL

....ice thing about ....oise gates is ....emove noise without
...urbing the sound quality.

David


Classic. LOL.

Wayne

Think of it like this, you walk into a room and the light switch will only
come
on at a particular loudness, lets say as loud as the sound when you just
slamed
the door. It turns on the light and you walk across the room to the other
door
open it and slam it closed and the light go's out.







Ok I've got one- you're God ok? and if you only want saints in heaven you would
set your pearly gates threshold really high but if your willing to let
republicans in you would set your threshold really low. However even at the
high saints-only pearly gates setting some republicans would still get in if
they enter at the same time as the saints but you (God) will not notice them as
much.

"Phoephus" read this in the National Enquirer :

Ok I've got one- you're God ok? and if you only want saints in heaven you
would set your pearly gates threshold really high but if your willing to let
republicans in you would set your threshold really low. However even at the
high saints-only pearly gates setting some republicans would still get in if
they enter at the same time as the saints but you (God) will not notice them
as much.



LOL. Too bad its gonna be lost on most of the people.




-- TAPKAE
http://tapkae.com

"We're the cleanup crew for parties we were too young to attend"
(Kevin Gilbert)