I’m using Audacity 2.0.1 on a Dell computer with Windows XP. I record from the web and the radio and lately have been digitizing LPs (through a stereo jack cord from receiver to Line In). I’ve got my Input level set at 6, which generally puts the blue max indicators on the meter at just below -6db, within the suggested range to avoid clipping.
Shouldn’t the wav form be bigger, though? It’s quite narrow, with lots of gray space above and below (in normal view). In Aud 1.2.6 (which I used for years) you could definitely see when you were clipping or close to it. I’m just wondering if my level is in fact too low. I guess I’m being a little too nervous, as the setting on the Input Level Meter should suffice; I’d just like the graphic as an added means of measurement. Kind of like using your trip meter and your gas gauge.
(Also, the wider wav form made it easier to see little clicks that Click Removal might have missed.)
The height of a new recorded track should be similar to 1.2. If you want a single track to fill the vertical height, set “Automatically fit tracks” in the Tracks Preferences .
You can turn on View > Show Clipping to mark any clipping with red vertical lines.
I might not be using the right nomenclature. I mean I want the blue wav form to better fill the space it’s in, not have the tracks fill the screen (which is what happened when I checked the box you suggested, then started and stopped recording). I’ve attached some screen shots showing a form in 1.2.6 and one in 2.0.1. The view in both is Normal.
Maybe this isn’t important; I just feel I can set my input level easier with a more pronounced graphic. Thanks.
You can probably increase your recording level so that it is a little higher than the first picture. -6 dB is just a guide - the important thing is to stay clear of 0 dB at all times during the recording.
The second picture is a bit too high as a recording level (it looks like it’s touching the bottom of the track in a couple of places.)
When the recording is finished you can use the Amplify effect to bring the level up to 0 dB if you wish.
2.0 should not be recording at a different level than 1.2 if your input device is the same and the output it’s sending is at the same level, however 0.6 on the slider does not equate to any particular resulting recording level.
If you don’t want the tracks taller then another way you can judge levels is to float the Meter Toolbar by grabbing and dragging at the left edge, then drag at the bottom right to make it wider.
Another way to judge the levels is to switch the view to Waveform (dB) rather than the linear view.
To do this one-off click on the Litttle-Black-Downward-Pointing-Triangle in the Track Control Panal to the left of the waveform - you will observe that in this mode the same signal fills the waveform display much more
To set this view to be your default, go to: Edit>Preferences>Tracks and reset the Default View Mode
This way your meters and you waveform display will both be using the same units (dB)
Actually, my devices are different. I was using 1.2 on a Dell with Windows 2000, and now am using 2 on a newer Dell with XP. So that might make a difference. I did increase the input level so it wasn’t quite so timid, and the wav form got a little wider and easier to see. HOWEVER, it still doesn’t seem to be a reliable indicator of volume level. In the screen shot below, the red lines would indicate clipping (am I reading that right?) but the blue wav form doesn’t reach the edges of the track, let alone go over them. Yet the tutorials and Help say that that’s how you can tell if you’re getting clipping when you record. So how does one judge if that’s happening?
However if you are not zoomed in enough and there are only a few samples clipped amongst quieter surrounding audio, then the level displayed in the waveform in the vicinity of the clip area may still appear to be well below than the clipping level.
If the clipping is where you put the record on the turntable then it looks as if you could increase the input level a little more.
In this case, I was recording off the radio. The tuner drifted off of the frequency, and as I was frantically tuning the station back in, I passed across another one, which is what I think the clipped portions show. The rest of the time, the meter was bouncing up close to 0, so I’m not sure I can push it any higher.
Not to belabor this, and I appreciate the time you’ve put into what is probably a minor issue, but I feel as though my last question has not been answered: Why are the red lines showing up if the blue form is not hitting the edges? If for some reason “show clipping” is not on (and please remind me where to find it; I’ve been looking through the Help but can’t seem to locate it), how will I know if clipping is occurring? Which do I trust: the red lines or the blue form? (And shouldn’t I be able to trust both?) Thanks.
When zoomed out that far, it is possible that the blue line that has clipped is only one pixel wide in the display. This one blue pixel will have been replaced by a red pixel in order to show that clipping may have occured. You need to zoom further in to this wave form to be able to see the clipping points. Use View > Show clipping to toggle the red lines on or off.
We’re going on about this because slightly low, gentle recordings can be easily cleaned up with Amplify or other tools. Overload and clipping are permanent distortions and may kill a show. Stark difference.
While you’re Normalizing or Amplifying to 0, please note that in some conditions, converting that show to MP3 will cause overload and clipping. The show in MP3 is not the same show in WAV or AUP. Snugging your show right up against the 0 level is very dangerous and in sometimes hidden ways.
I record off-air shows and I never get much closer than about -4 to -6. Even the serious broadcast compressors up on the hill occasionally let stuff through and I leave room for it.
To repeat, View > Show Clipping always shows clipping. It shows every single audio sample that is clipped (not by replacing the blue sample dot, but by adding a red vertical line at that point).
If you are zoomed out, you cannot trust the blue waveform to denote clipping if that clipping is just a few samples (microseconds) of audio and the rest of the audio is not clipped. This is because when you are zoomed out, Audacity cannot display all the samples - at 44100 Hz project rate there are 44100 samples for every second of audio. All Audacity can do if you are zoomed out is to display each pixel at the average amplitude of whatever length of audio that pixel represents. If a pixel represents one second of audio, only one sample out of the 44100 is clipped and the rest of the audio samples peak at 0.5, that pixel will display at 0.5.
If you want another indicator of clipping that you can trust, look at the red hold line to right of the recording meter. That illuminates (and stays illuminated after recording) as soon as four or more consecutive clipped samples are detected. See http://manual.audacityteam.org/o/man/meter_toolbar.html#annotated for more explanation.
If the meter was already bouncing close to 0 when the radio was playing normally, then you should turn the Audacity input slider down a bit, though your waveform extract indicates the level when the radio was playing normally was a little lower than it needed to be. Not much lower, because 0.5 on the waveform is actually -6 dB on the meter. Waxcylinder already explained that to view the waveform in dB as the meter sees it, you have to change the waveform to dB view.
