low recording level with high hissing noise

media4u wrote on 12/15/2002, 11:55 AM
Hello all!
I'm very new to pc audio recording, so I may need you guys to hold my hand to walk me through. I recorded a sermon at my church and the recording level was very low. I would like re-make the tape, but when I increase the volume I get a high hissing noise. How can I amplify this speech and remove all the hissing sound that came with it. Any kind of help would be appreciated
Thanks

Comments

momo wrote on 12/16/2002, 11:41 AM
There’s not a lot you can do since amplifying the signal just amplifies the noise. The only thing I can recommend is what I did a ways back when extracting audio from old cassette-tapes; check to see if you have a Paragraphic (or ”Parametric” – can’t remember) EQ, and add this as a track-enabled effect. It allows you to determine and isolate a frequency (x) and amplitude (y) range that you can slide back and fourth over the whole frequency spectrum. Play with this until you isolate the noisiest part of the spectrum, then you can filter it out (sort-of) by bringing down the EQ level within that range. It’s not a perfect solution, but it’s better than nothing. And even if you record it again with a good hot signal, you'll always have hiss if you're sourcing with a cassette tape.

Geoff_Wood wrote on 12/17/2002, 6:10 AM
Not clear if you are raising the volume externally before recording, or cranking it in Vegas (normalising even ?) after recording. If 'after' then the lower the original signal, the closer it is to the 'quantisation noise' floor. Subsequent raising of the gain will bring up the noise by the same amount, so it is important to record the track as 'hot' as possible.

If you are raising the gain prior to recording, any noise present in the recording chain and room withh be amplified as well.

Moving the mic/s closer to the sound source, or a more direction mic may help there.



geoff
fluval wrote on 12/17/2002, 11:02 AM
sonic foundry has a noise reduction program that works very well.
I have tryed a few other noise reduction porgrams and I think this is the best one out there.
Hammer wrote on 12/18/2002, 8:21 AM
Wow. I was gonna ask the exact same question. What sonic product offers noise reduction? To my surprise, a cheezy a wave editing app that came with Nero 5.5 had exactly what I was looking for but it does affect the speakers voice some. You select the "noise" in the sample and it determines the frequencies that are in that selection. Then you "Remove noise" and it pulls those frequencies out(has a slider so you can determine if it just reduces or completely removes). Does a pretty decent job but it does leave you with some artifacts in the speakers voice. Kind of a mechanical or hard clipping effect. Is there a tuturial for the plugins that come with VV. I didn't see any and I don't know enough about audio editing to understand what effects I should attempt to use to lessen that effect, if it's possible.

Thanks
momo wrote on 12/18/2002, 3:58 PM
According to the “products” pull-down menu above, Sonic Foundry Offers “Noise Reduction 2.0”

http://www.sonicfoundry.com/Products/showproduct.asp?PID=14

...which is a Direct X plug-in that’ll work with Sound Forge, Vegas, and any other Direct-X compatible editing application. Your project sounds like a perfect application for this. However, if capturing “a” sermon is the prime goal (as opposed to that particular one), then I suggest you try to record it again with a stronger, or “hotter” signal: get the mic close to the source – the further away it is, the more noise you’ll get, as Geoff points out above. If your main aim is to do all you can to restore a quiet, noisy signal, the software above will help, although you may be able to do quite a bit with simple EQ methods as I pointed out above. It's cheaper, anyway.

good luck!
Hammer wrote on 12/19/2002, 2:48 PM
Thanks momo. Ouch, wasn't expecting a price tag that high. Looks like a very capable product though. I'm afraid unless it came with a very good tutorial it would be hard for a novice like me to achieve similiar results. Are there any good on-line guides to digital audio processing, or books?
momo wrote on 12/19/2002, 11:34 PM
A great place to start is http://www.prosoundweb.com/studyhall/ab_index.php

I learned a lot (and am still doing so) from this site. There's tons of others just as good.

hope that helps

momo