How to reduce noise?

n-Track Studio Discussion Forum
2

Hi
I downloaded N-Track Free to use for editing audio lectures mp3 files and It doing a great job for me in editing tracks but I need to reduce noise and improve lecture voice quality and since I have zero knowledge in audio software I dont know if this is doable using n-track or not :)
please advise…
Thanks in advance
Rimoun

3

What type of noise would you be talking about? Hiss, background noise like echo? Provide some more detail, system used ect ect…

PACO

4

Hi Paco
Hmm since i’m not an audio expert i can just predict that its background noise… and also the audio recorder was not close to the speaker’s mouth so his voice is not so clear…
is that helpful or should i upload the file for you to advise me what to do to improve it?
Thanks for your help :)

Ah… not sure what do you mean with system but anyway we have recorded the lecture using olympus wma recorder and i converted it to mp3
bitrate: 32000
audio channels 2

Rimoun

5

Without getting closer to the source this will prevent you from hearing the speaker especially if your in a class room or lecture hall. If you can’t get close you might want to place the mic between an open book facing the speaker. This could prevent other sounds like room echo from bouncing of the walls/ceilings back at the mic. The open book, if faced directly at the speaker might isolate his/her voice. Have you every seen those satellite looking clear like dishes at football games. They use those to isolate the audio on the field while blocking audio from the crowd behind and from the sides. Same principle here. Thats all I can think of.


PACO

6

Aha… that’s good information. I will try this trick next lecture :)
But for the already recorded one is there anyway to improve quality using ntrack or other software?
Regards
Rimoun

7

There are software applications that reduce background/ ambiant / room sound /noise but the are none free as far as I know. Sometimes you can get a better voice sound by working with the EQ - N_track has a track EQ under the VU meter for each track. Sometimes ( note Sometimes) you can raise at about 500 and bring up a voice, but this may also be where the noise is located. You can do a “sweep” to try and find where the most noise is located (but it is usually not a simple frequency but a combunations of frequencies) Bring up the EQ and select a node ( a dot at one of the frequencies) and raise or lower the level several db. Slowly move the node across the spectrum until you hear a change that is an improvement. To bring up the voice raise the Db, to lower the noise, lower the Db - about 10 Db will tell you what you have, but less may be where you want to settle. This is art suing science and every instance is differnet according to the sercumstances. I hope this helps,
Bax

8

Hi rimoun. I’d be happy to take a look at the file. For the future, would you be able to arrange a clip-on mic etc?

9

Hi Reafir is a free plugin that might help you, see below for description in the section called subtract.

http://wiki.cockos.com/wiki/index.php/ReaFIR#Subtract

Below is the link to download the plugins, you would need to put them in the n-track vst folder or tell n-track where to look for them. Someone else will be able to tell you how to do that if you struggle.

http://www.reaper.fm/reaplugs/

Nick

10

@bax3 thanks allot for this information :) … Will the full version of n-track help me in that? u know the free version have a limited EQ…

@TonyR http://hotfile.com/links/122580151/5960ea2/Al_E7bat_-_Eng_Rafik_Onsy.mp3.html (its in Arabic so u may not understand whats going on :) … thanks in advance.

11

I am not acquainted with a free version of n_track. There is a “demo” version that I know of and it has a limited trial period - after that the demo will put a tone/noise in to the recording about every 30 seconds or so unless you extend the demo time or buy the software. The demo version has all the features turned on as far as I know.
Bax

12
  • Free version is available on mac app store :)

    - by the way I managed to improve quality by decreasing base and increasing treble but i still have a problem… there is some sound appears when the speaker raises his voice its like the sound of clicks or something alike… is there anyway to get rid of that?

    Regards
    Rimoun
13

Zoom in on the track. You will see the spikes. Drag the area and click the red cross in upper tool bar. Or use the fade in/out buttons on the selected area for a softer edit.

14

Hi TonyR
Thanks for the tip
I think the red cross will make the selected area silent right?
If so It will not be a good solution as I here these clicks along with the speaker’s speech so if i made it silent there will be cuts in the speech.
concerning the fade… do you mean when i fade the voice out to 80% for example and then fade it in in this area that will remove the clicks sound?
Regards
Rimoun

15

Yes, rimoun, you are getting the idea and you are quite correct that the red cross will silence the selected area and the same by degrees using the fade option. You might want to try some of the tools in Audacity http://audacity.sourceforge.net/ which is free. It has some good noise reduction and sound processors like Nyquist Noise Gates etc.

16

Thanks allot TonyR I will give it a try :)
really learned allot for you guys here :)
Regards
Rimoun