MP3 file sounds normal, Audacity file v distorted! Why?

[kozikowski]

The short, bumper-sticker version is apply normalize to the clip you supplied to us.

Select the whole clip by clicking just above MUTE.
Effect > Normalize: [X]Remove DC, [X]Normalize to -3.2 > OK


The analysis program is a plugin written by flynwill (acx-check.ny, attached) Put that in your Audacity plugins folder just like an external effect or filter. Restart Audacity.

Select the whole clip by clicking just above MUTE.
Analyze > ACX Check > Wait.

Do you know what the ACX values are and what they mean?

Koz

[BonnieVO]

They are going to ask you about your playback system. How are you listening to the work? Model numbers?

I need to find out what these are! (model no's).

What are the settings in your Audacity Device Toolbar?

I have just changed to MME - I had it on Windows Direct Sound previously, thinking that was the correct setting. This seems to have worked for most but not all of the tracks, the ones now giving trouble - a juddering effect like I had before the drunken one! - are audacity files!

http://manual.audacityteam.org/o/man/de ... olbar.html

Does it misbehave when you listen on headphones?

yes, only listening via headphones.

Earbuds may not be very helpful, but some in-ear earphones might be OK.

Going through your other messages, many thanks again for all the help!

[FekketCantenel]

Bonnie, you're in good hands. If you'd like to compare notes on submitting to ACX (which I'm about to do), please let me know.

Meantime, I have a quick, relevant question for Koz.

Select the whole clip by clicking just above MUTE.
Analyze > ACX Check > Wait.

Does one use the ACX Check on the Audacity .aup work files (before exporting) or on the final MP3s? Because in my experience (and you mentioned this in the other thread), the MP3s' noise levels get wonked around during export and don't pass the tool's requirements, even if the original work file did. Does the state of the MP3 not matter if the original was fine? Or should I be adjusting the original so that the MP3 ends up within parameters?

[kozikowski]

It's a little more magic than that, although that would be magic enough. MP3 works by figuring out, magically, which sounds you need for your show and which it can throw away. As the MP3 quality settings get lower, it throws more and more away. You would think that the show would get quieter and quieter as pieces were deleted, but some delicate overtones and harmonics actually subtract from the show volume. So when MP3 deletes them, the volume goes up.

Right away, there's storm clouds.

So it's possible to set the blue wave peaks to -3.0dB as in the ACX specifications, but have the final MP3 come out over that, -2.9dB or -2.8dB. That's why the final pass in almost all my tool lists is to apply Normalize at -3.2dB. The difference between -3.2dB and -3.0dB is the fuzzy zone where MP3 is allowed to do its work without losing conformance. If that's too tight for you, by all means pick a different number, but also remember the values affect each other, so don't wander too far away.

By all means do open up your MP3 in Audacity and re-apply the analysis tool. You don't have to work in a vacuum (It hurts my ears when I do that).

I've never heard of MP3 affecting the noise level, but another thumby rule is never submit with borderline values. If your show noise comes in at -61dB and Anything At All goes wrong, you could fall out of compliance (-60dB).

We don't have ACX blessing for our tools. We're just going on their published specifications and our success rate.

Koz

[BonnieVO]

Bonnie, you're in good hands. If you'd like to compare notes on submitting to ACX (which I'm about to do), please let me know.

That sounds great, though that may be a few weeks down the road for me, I'm just doing my first few takes in my new booth and trying to get to grips with the audacity machine, though hoping to be ACX-fit very soon, as I've an audiobook in the wings....

[BonnieVO]

I'm still having sound distortion in playback.

They are going to ask you about your playback system. How are you listening to the work? Model numbers? - Can you tell me what these are please? I haven't been able to figure it out.

What are the settings in your Audacity Device Toolbar?

http://manual.audacityteam.org/o/man/de ... olbar.html

Have switched between 'MME' and 'Windows Direct Sound' to see if this is the issue, but this is working sometimes (the track becomes perfect) but not all. I still get a flickering over the track, both the mp3s and the audacity files. Have been working through all relevant (I think!) suggestions of the manual to try and fix the problem but no go. Could 'audio host' be the issue here? I'm on windows 8 - the manual tells me that MME is usually the most compatible...

Help!

thanks

[kozikowski]

You may be in good hands, but you'd be in better hands if I was a Windows elf. I'm not. If you're having Windows sound problems, we have no choice but to wait for someone who can speak Microsoft. Sorry.

Koz

[BonnieVO]

Ok Koz, thanks anyway. Can I post a new topic on the forum? - as I have come some way since my original query and the question/issue has now changed slightly.

[Gale Andrews]

Can I post a new topic on the forum?

Yes, please do http://forum.audacityteam.org/posting.p ... =post&f=46. If the problem is with Windows audio, please describe what the issue is as clearly as you can.

Post the information from Help > Audio Device Info... top right of Audacity. Right-click in the Audio Device Info and choose "Select All". Right-click again and choose "Copy". Then paste into your post.



Gale

[BonnieVO]

The short, bumper-sticker version is apply normalize to the clip you supplied to us.
Select the whole clip by clicking just above MUTE.
Effect > Normalize: [X]Remove DC, [X]Normalize to -3.2 > OK
The analysis program is a plugin written by flynwill (acx-check.ny, attached) Put that in your Audacity plugins folder just like an external effect or filter. Restart Audacity.
Select the whole clip by clicking just above MUTE.
Analyze > ACX Check > Wait.
Do you know what the ACX values are and what they mean?
Koz

Hi again Koz - touching all wood as I write.... I seem to have finally resolved my sound problems. Seemingly I had to install the latest driver for my pre-amp, a process which somehow didn't happen when I bought it (I also recently changed PC). Don't completely understand why, but hey, all is smooth as a millpond right now. Hallelujah. Many thanks to you for all the help and tips . Especially for the ACX checker plug-in, it's brilliant. Now I can finally get some work done