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shorter126
09-17-2012, 12:20 AM
Hi all

I've been trying to deal with an issue in Adobe audition that causes a great deal of frustration for me. When i record my podcast I have no "noise" in the background , thanks to a noise gate on my compressor and a ground loop isolator.

However during post production, when i normalize and use the multi-band compressor tool , hissing is introduced. I hear a lot of podcasts out there where this hiss is not present. Am I doing something wrong ?

Thanks,:confused:

mcphillips
09-18-2012, 03:51 AM
A compressor reduces audio dynamics and, therefore, reduces your signal-to-noise ratio. Think about it like this. If your compressor reduces your overall volume by 10 dB on a peak, when the compressor "relaxes", or does not attenuate, it essentially turns UP your volume by 10 dB. So, if the normal noise floor on your audio is -45 dB, after running the audio through a compressor set for 10 dB compression, your noise floor is only -35 dB. That's one possibility.

Why don't you post a before and an after clip of your audio so that we can try to hear what you're doing? Compressors are difficult to set just right. Most people set them incorrectly. There could be something else going on.

andrewzarian
09-18-2012, 08:09 AM
I know Mike would have an answer for this :)

shorter126
09-18-2012, 11:13 AM
My last episode of tektalk5 was recorded and processed with Adobe Audition. You can hear it here (http://tsquareg.net/wii-u-is-ready).

A sound file with no compression is attached77

Thanks a bunch !

mcphillips
09-18-2012, 07:56 PM
I apologize if you've posted this information elsewhere already, but what mic and mic preamp are you using? How is your preamp or mixer connected to the computer? What sound card are you using? How far away from the mic are you talking? What sort of acoustical treatment do you have in your room?

Something doesn't sound exactly right about your raw file, and I can't put my finger on it. If you're using Audition to correct a deficiency, you're also amplifying the deficiency.

shorter126
09-18-2012, 11:24 PM
I apologize if you've posted this information elsewhere already, but what mic and mic preamp are you using? How is your preamp or mixer connected to the computer? What sound card are you using? How far away from the mic are you talking? What sort of acoustical treatment do you have in your room?

Something doesn't sound exactly right about your raw file, and I can't put my finger on it. If you're using Audition to correct a deficiency, you're also amplifying the deficiency.

Hi,

The equpment i use is as follows
Heil PR40 microphone,
Mackie Pro FX 8 mixer,
MDX4600 Compressor Limiter Gate

I also use an external USB sound card which has a ground loop isolator attached. The mixer is attached to the sound card through the line out port.

I am fairly close to to mic but not speaking into it directly.

My studio has nothing more than heavy curtains in it.

Thanks !

mcphillips
09-19-2012, 03:46 AM
Are you speaking into the side of the PR40 instead of into the end? Your voice sounds off-axis.

shorter126
09-19-2012, 05:32 AM
Are you speaking into the side of the PR40 instead of into the end? Your voice sounds off-axis.

I do speak more into the side rather than full on !

mcphillips
09-19-2012, 06:02 PM
You must speak directly into the END of the PR40. It looks like a side-address mic, like the Audio-Technica AT2020, but if you talk into the side, you are "off-axis", and the sound is terrible. The optimum distances is 3 to 4 inches, based on your room acoustics.

shorter126
09-19-2012, 11:13 PM
You must speak directly into the END of the PR40. It looks like a side-address mic, like the Audio-Technica AT2020, but if you talk into the side, you are "off-axis", and the sound is terrible. The optimum distances is 3 to 4 inches, based on your room acoustics.

Thanks for that advice. I used to see others speaking side ways to the mic and assumed this was okay. Is there any way I can reduce the "noise" afeter I use the compressor in Audition. I don't really want to use their noise reduction !

mcphillips
09-20-2012, 03:41 AM
You should minimize the noise in the room such that you do not have it in the recording. Removing noise after the fact is almost impossible. It's never perfect. Please record a new (raw) segment and post it. Talk directly into the mic about 3" away.

shorter126
09-20-2012, 01:16 PM
78
Here's the new one with me recording directly into the mic.

Regards,

mcphillips
09-21-2012, 10:30 AM
The difference to my ears is significant. What do you think? There may be some room or fan noise, but the audio is good.

shorter126
09-21-2012, 11:55 AM
Great news. I'll keep on working on the background noise.
Thanks a million for your help.

jamesdelfresco
09-24-2012, 02:20 PM
Mike and Shorter I learned a lot from this thread. Thanks for the info Mike!