Audacity Forum

Hey there, i'm new to Audacity and the community, and i've encountered something i'd like some input on.

When i record speaker output (whether it be a song, or a live radio stream) the recording sounds fine in audacity. Once i export to mp3 or wav and play back the file i hear background noise.. a hissing or static sound that i don't hear at all in the original recording when played through audacity. I've tinkered around with most of the settings to trial and error an idea as to what is happening, but to no avail. Again, the hissing or static sound (background noise) is only coming through during the conversion process when i save a recording to wav or mp3 format. I dont have any problems with the recordings... they are perfect... when they are first recorded before saving. Any ideas??

I realize this may not be an audacity issue, and hoping someone can offer some ideas or suggestions to help me better hunt down and tackle this problem. FYI i'm using the lame_enc.dll for mp3 encoding.

I like this one. It's impossible, but clearly happening.

Can you post--on some other web site--a short sample of the work? Use a WAV. I don't want to have to sift through MP3 damage. Include a sample with silence or no show for a second or so.

And do try this. While a sample show is on the timeline, insert a second of silence from the Audacity Generator. See if that particular sample is noisy as well.

We are splitting the pipeline up into two in order to determine which half is damaged. It's possible both are. Wouldn't that be fun?

Koz

Yeah, that's what i said.. makes no sense to me why the noise would only be heard after saving the file and playing back, and not on the actual (unsaved) recording.

I did what you suggested. You can find a test.wav file on the following link. I recorded a few seconds of silence before a streaming radio commercial and then inserted 5 seconds of audacity silence to the end of it. The noise is heard throughout the entire thing. Check it out.

FYI i'm using a soundblaster audigy sound card that has been excellent for me.. i've never had any issues with it. I use this system to stream music to my home theatre system in dolby surround. Never heard this noise before.

http://www.mikeshearin.com/test.wav

mike656 wrote:The noise is heard throughout the entire thing. Check it out

The noise level during the "silent" sections is very low (around -80dB). I suspect that the problem is with your media player or its settings. If you import that sample back into Audacity, does the noise go away?

I bet you're turning the volume all the way up to hear that. I get an 80dB noise floor, too, and that is 20dB beyond audibility, whether you're a young woman or not. I'm tucked into a pair of Pro-4AA headphones and my heartbeat is louder than your noise.

Effectively, the portion before and after the Geico spot is dead quiet. The front portion is very, very slightly less dead than after. But they're both dead.

That's the limit of all "normal" sound cards. They all hit bottom at -96 and because of the limits of a $12 sound card, the analog electronics die a lot sooner than that, usually in the -70 range--sometimes -60 or so. The fact that your audio trash is in the -80 range is remarkable.

I would be listening to this work on Something Else. Find a Mac somewhere. Those have very well behaved sound systems.

Do you have capture software on your machine (like I do)? Do you have any software at all that touches the sound services? TV or FM tuner? Vonage or Skype?

I keep glancing over at my right-brain for a hint, but he's out scarfing up some Ben and Jerry's.

Koz

I haven't toyed with the sound levels at all actually. My sound blaster volume levels are at 70%, which coincides with the windowsxp volume control and when i play back the recorded saved file on winamp i'm playing it at 23%. (turned down) I'm not sure about the settings on audacity as i'm still trying to get a feel for it. All i do know is that the volume level is equal on playback as it is live when i'm listening to anything else on my system. Still no reason ( to me ) why i would hear noise only after saving a file and not on the unsaved recording.

Are you suggesting that i toy with the volume settings and try to turn everything down? If i do this i won't be able to hear much at all, but i will do it and try more trial and error.

When i load the file back into audacity i dont hear the noise. I dont hear any noise through audacity at all. Its only when i play back the saved file in winamp. I also tried winmedia player and i dont hear any noise at all. So far i'm only hearing this noise when i play a recorded file through winamp. Strange. Perhaps i've isolated this to winamp... but no, on the contrary to what you said, i'm not cranking everything up to hear anything, i've actually got winamp turned down low (23%).

mike656 wrote:When i load the file back into audacity i dont hear the noise.

As we were saying, there isn't any (well, very very little)

mike656 wrote:Strange. Perhaps i've isolated this to winamp...

I think that's your answer. Now why would WinAmp be noisy? Have a look in the WinAmp plug-ins and see which output plug-in it is using. If not already selected I think that you should find a "Direct X" output option, give that a go and see what happens.

Thanks for the both of you who helped me with this. I've fixed the problem.

I'm not sure what , if any noise, you were able to hear, but when i was hearing the noise.. it was VERY LOUD! I made a 5 second recording of silence and played it in winamp. I heard LOUD LOUD hissing noise. I lowered the volume to 1% and the noise stayed the same.. no matter what volume winamp was at, the noise was just as loud. When i turned the volume to 0% theres nothing (of course).

So this led me to think something was weird with winamp or my sound drivers. I delved into this deeper. What was strange to me was that win media player was fine.. no noise at all. So i opened up the sound blaster interface and checked everything out thorougly. I discovered that i had to turn the equalizer on and turn the level all the way down to -24 to get rid of the noise i was hearing (lowest setting on my eq).

I went through the winamp settings and was able to reset some things. Apparently winamp was cranking the levels up so high that i was able to hear this loud noise... even though winamp itself was at a very low level. It was a combination of driver equalizer and winamp default output dll. Once i reset them, and reset the default sound devices through win control panel, all was good. No more noise! Whoohoooo.

Again, thanks. I knew eventually i'd figure it out... was just a matter of tinkering with. I uploaded a new file and i'd like you to check it out and tell me if you find anything wrong with the volume levels (since you guys brought up the topic). I think its fine now but want to get your opinion.

http://www.mikeshearin.com/anothertest.wav

mike656 wrote:I uploaded a new file and i'd like you to check it out and tell me if you find anything wrong with the volume levels

If that is the straight recording level, then I would say it's not far off.Is that recorded of a radio / TV? If it was, then you could possibly turn up the recording level a little, but you are only about -5dB down, so you wouldn't want to boost it much.

-5db down? When recording i'm reaching -6db on audacity (if i'm reading it right).

Yeah i'm recording off of streaming radio broadcasts.

By increasing the recording level, are you meaning to increase the level of "What U Hear"?

The audacity volume control is maxed out so i'm assuming thats what you mean....