It's Audacity... or 2 mikes... or me...

minime · Post by **minime** » April 12th, 2006, 2:09 am

I've done 2 recordings using Audacity and 2 different mikes. When I record - no worries. There's some background noise, so I use the 'noise removal' facility, with or without the 'amplify' function as described in the Audacity FAQs on LibriVoxWiki...

And every time, after using the noise removal function, it comes up with a funny metallic-ish background sound. If I increase the level of noise removal, it distorts my voice. If I decrease it, the funny metallic-y noise gets worse. That noise can only be heard through headphones; if I play my recording back through the computer speakers, it sounds fine (which it why I didn't pick up this problem after the first recording and edit... grrr...)

Any ideas?

Thanks. I'm pretty keen to try and contribute to this fantastic project.

Sharmini

Post by **hugh** » April 12th, 2006, 4:46 am

hi sharmini, yes the audacity noise removal is not very ... kind ... to recordings. the background noise likely comes from your mic or your computer's soundcard.

there's one good solution to that proble (others may post some other suggestions here): it's a USB mic. I made the switch & it made a huge difference - recordings much clearer.

Logitech makes a bunch of cheap USB microphones - (about $30) ... either headset or desk mic. I use a Logitech 250 USB mic.

kri · Post by **kri** » April 12th, 2006, 6:55 am

Yeah, Audacity's noise removal is notoriously crappy. There are a few ways that you can reduce background noise a little. However, I'd definitely get a new USB mic. In the meantime...

1. Make sure that your input levels for your microphone are at the highest possible. This way you don't have to increase the volume after you've recorded, and in you'll avoid increasing the background noise. Doing this will cut down a little on background noise.

2. Get a good quality sound card. This is probably not feasible, as getting a USB mic is much much cheaper.

3. Avoid Audacity's noise removal at all costs. It really isn't the best feature of Audacity. If you absolutely can't get a new mic, and increasing your input levels doesn't help a lot, post in this forum (Need Help) with a request to someone skilled in noise removal to fix up your files. There are volunteers who don't use Audacity, and some are really familiar with the noise removal of their respective programs.

Fox in the Stars · Post by **Fox in the Stars** » April 12th, 2006, 7:26 am

You might also try turning Audacity's noise removal level down, if you haven't done this yet, like experiment with nudging the slider toward "more noise" one notch at a time. This might not work; by the time it gets the tinniness acceptably low it might leave pops in the silences, but I think turning it down can sometimes get it sounding a bit less crummy.

Aldark · Post by **Aldark** » April 12th, 2006, 7:33 am

What I did was create an .aup file I call "nice dead silence" - it has segments of .25sec, .5sec, 1sec, and 1.5sec of 100% silence.

When I'm editing I copy from the "nice dead silence" file and paste them into my recording as needed and where an appropriate amount of dead space is needed.

It was great when I was doing the Devil's Dictionary because the timing between reading entries into the dictionary could be evenly spaced out.

It may make editing longer... but it works for me so far in my limited recordings.

- Scott

kayray · Post by **kayray** » April 12th, 2006, 9:08 am

Scott, I've never actually heard one of your recordings I guess, (can this be? I used to know every volunteer's voice...) but I've gotta warn against using actual true DEAD silence as filler in recordings. Ambient room noise is great to use that way, but patches of true dead silence sound extremely peculiar.

Aldark · Post by **Aldark** » April 12th, 2006, 10:16 am

kayray wrote:Scott, I've never actually heard one of your recordings I guess, (can this be? I used to know every volunteer's voice...) but I've gotta warn against using actual true DEAD silence as filler in recordings. Ambient room noise is great to use that way, but patches of true dead silence sound extremely peculiar.

Well - I'd have to listen to them specifically again, but when I record them I don't mute the microphone or anything I just don't breathe.

As for my recordings I think I only have 2 under my belt so I'm not shocked if you haven't heard me.

kayray · Post by **kayray** » April 12th, 2006, 10:26 am

Aldark wrote:
kayray wrote:Scott, I've never actually heard one of your recordings I guess, (can this be? I used to know every volunteer's voice...) but I've gotta warn against using actual true DEAD silence as filler in recordings. Ambient room noise is great to use that way, but patches of true dead silence sound extremely peculiar.
Well - I'd have to listen to them specifically again, but when I record them I don't mute the microphone or anything I just don't breathe. :)

As for my recordings I think I only have 2 under my belt so I'm not shocked if you haven't heard me.

Oh excelent, that's the way to do it. Some software will let you insert ABSOLUTE silence -- that's what sounds odd. You're getting ambient room noise which likely sounds fine :)

Aldark · Post by **Aldark** » April 12th, 2006, 10:54 am

I just did a double-check (since I carry those files with me to work) and yes, it is ambient noise.

It is a lot better than the swearing I do after mistakes... or the burps and things like that... I'm sure that would add variety, but then it would corrupt the orginal documents.

minime · Post by **minime** » April 12th, 2006, 2:35 pm

kri wrote:Yeah, Audacity's noise removal is notoriously crappy. There are a few ways that you can reduce background noise a little. However, I'd definitely get a new USB mic. In the meantime...

1. Make sure that your input levels for your microphone are at the highest possible. This way you don't have to increase the volume after you've recorded, and in you'll avoid increasing the background noise. Doing this will cut down a little on background noise.

2. Get a good quality sound card. This is probably not feasible, as getting a USB mic is much much cheaper.

3. Avoid Audacity's noise removal at all costs. It really isn't the best feature of Audacity. If you absolutely can't get a new mic, and increasing your input levels doesn't help a lot, post in this forum (Need Help) with a request to someone skilled in noise removal to fix up your files. There are volunteers who don't use Audacity, and some are really familiar with the noise removal of their respective programs.

Ok - I guess I can invest in a new mic. If I got a reasonable quality mic, are we suggesting that it would be ok to not use any noise removal?

I have the input levels turned up as high as they will go.

Thanks everyone.

kri · Post by **kri** » April 12th, 2006, 2:41 pm

If you get a mic that plugs into your USB port, your only problems with sound quality will be due mostly to the quality of your microphone. Hugh's suggetion of the Logitech microphone is a good one, as there are many volunteers here who use the same mic and have been very happy with them. You could have the crappiest sound card in the world, or even be using the sound card on your motherboard (which aren't known for their quality), or the best sound card that it is possible to buy, and it wouldn't make any difference if you were using a USB mic.

Fox in the Stars · Post by **Fox in the Stars** » April 12th, 2006, 2:47 pm

My recordings with my USB mics (a Logitech 200 and a Logitech 250; both are good) are generally fine with no noise removal. I've experimented with doing it/not doing it (also using Audacity) and at last I prefer without. At worst it has that kind of ambient white noise that takes you back to pleasant memories of cassettes and LPs. ^_~

kayray · Post by **kayray** » April 12th, 2006, 2:47 pm

minime wrote:
Ok - I guess I can invest in a new mic. If I got a reasonable quality mic, are we suggesting that it would be ok to not use any noise removal?

Yes yes yes! It's MUCH better never to use Audacity's noise removal. Honestly, I'd rather hear a small amount of background noise than those nasty metallic whirring artifacts. A $30 USB mic *should* eliminate most noise, anyway. :)

minime · Post by **minime** » April 13th, 2006, 12:33 am

Thanks again everyone - I have just invested in the recommended Logitech mic - I am away at Easter, but will re-record my chapters and see how they go... now that I've invested, I will have to do a few more recordings!

P.S. I'm assuming that the price quoted was Canadian or American dollars... either that or I paid too much (in Australia)

ChipDoc · Post by **ChipDoc** » April 13th, 2006, 1:22 am

I just ran a comparison and the thirty American dollars I paid for mine should tranlate into about forty Australian dollars.