Meter Toolbar

Peter 09Oct14: I have updated this page to cover the new default Gradient Meters.

ToDo-2 Ready for review and merciless editing.

• Bill 09Oct14: Peter, it looks like you've done your screen captures with the meter toolbar undocked. For consistency I think they should all be done either docked or undocked, and all have the same width (at least in the sections where the gradient and rms meter styles are compared. Also, should I work up a new horizontal / vertical comparison, or are you on that?
  • Peter 10Oct14: well spotted Bill - I undocked 'em to make the trim against a neutral background easier. I deliberately dropped the horizontal/vertical examples in order to shorten the page a bit now that it has grown. I thought that the text was clear enough with images as examples - and the previous examples were a bit ungainly (the vertical one anyway).
• Gale 09Oct14: At least I think each image pair should be docked or undocked. How about making the annotated pair only have the grab handle, and annotate the handle?
  • Peter 10Oct14: I'm thinking now that I'll rework all the images on this page so I can get same sizes per section and a clearer RP in the annotated section as Bill suggests - getting that particular screenshot was a tad tricky to show all that I needed to show. I'm thinking I'll do them all undocked.
• Peter 20Oct14: Ok, I redid all the meter images on this page, all undocked, the pair for both styles now identical size.

  ToDo-1For the annotated images I have been experimenting with the sizes, which do we prefer? The smaller ones start out the same as the images in the "Choice of meter style" section examples but copying them from Paint to PowerPoint for the annotation and then back to Paint again for export shrinks them. The bigger images come from resizing by stretching in PowerPoint - but note that this stretches the scale numbering on the meters.

Meter Toolbar displays the amplitude of audio being recorded or played in the project. It is an easy way to see if audio which is being recorded or edited is clipped, which results in distortion.

Contents

1. Choice of meter style
2. Drop-down Menu
3. What the bars and lines mean
4. Meter channels
5. Adjusting playback level
6. Adjusting and monitoring recording level
7. Undocking and Resizing

Choice of meter style

Audacity offers two choices of style for metering. You can switch between the two meter styles in the Meter Preferences dialog which is accessed by the Meter drop-down menu. For both styles, L shows the left channel and R the right channel.

Gradient Meter

These are the default meters for Audacity. Both the Playback Meter (loudspeaker icon) and Recording Meter (microphone icon) display in the same colors. The bars remain green until the signal reaches -12 dB then merge to yellow as the signal approaches -6 dB (which is a good maximum signal level to aim for). If the signal exceeds -6 dB the bars merge from yellow to red. The red color warns that the signal is becoming too "hot" (approaching 0 dB) and that clipping may occur.

RMS Meter

The Playback Meter has green bars and the Recording Meter has red bars. This style displays the the current RMS level of the signal in a lighter shade of green or red respectively, but the colour does not change when when the signal approaches -6 dB or 0 dB.

This was the previous style of meter used in Audacity. Users of earlier versions of Audacity may prefer to use the Meter drop-down menu to open Meter Preferences and change back to this style of meter.

Drop-down Menu

The drop-down menu on either meter (shown by the downwards-pointing triangle) lets you disable or enable the meters and open the Meter Preferences. The drop-down menu on the Recording Meter additionally lets you enable or disable monitoring of the recording level without recording a track. Another way to access the menu is by right-clicking on either meter.

Disable and Monitoring

• Disable Meter/Enable Meter: Turns the individual Playback or Recording meter off or on. When the meter is disabled it is gray and does not operate.
• Start Monitoring/Stop Monitoring (recording meter only): Starts/stops visual monitoring of the recording) level without recording a track. If you want to also hear the input without recording it, turn on Transport > Software Playthrough or enable direct hardware playthrough as described below. You can also start and stop monitoring by left-clicking anywhere over the Recording Meter.

Preferences

Selecting Preferences from the menu opens the Meter Preferences dialog which lets you change the meters' style, visual orientation, the scale format and more:

• Refresh Rate: Use this to set the refresh rate for the meters. A higher rate makes the meter show more frequent changes. Too high a rate can cause audio breakup on slower machines.
• Style: You can choose either the Gradient Meter (default) or the RMS meter.
• Type:
  • dB: Displays the meter with a logarithmic scale where the maximum level before clipping is 0 dB. This is the default view giving more detail for fainter sounds, corresponding more closely to how sound is heard. The minimum value of the scale can be changed in the Interface Preferences.
  • Linear: Displays the meter with a linear scale where the maximum level before clipping is 1.0.
• Meter Orientation:
  • Horizontal: Displays the meter at its default horizontal orientation, with the bars extending from left to right.
  • Vertical: Displays the meter vertically, with the bars extending from bottom to top.

Gale 09Oct14: I think the below section and the one on channels could be better sited directly below Preferences. Then user has more idea of managing the meters when it comes to adjusting levels.

• Peter 20Oct14: Trying moving these two sections as Gale suggested.

What the bars and lines mean

* Bill 09OCT14: Peter, I find the "RP" (recent peak) bar in the new gradient meter graphic almost impossible to see. Despite wanting to show reasonable recording levels, I think it would be worthwhile to either capture an orange/red "recent peak", or fake it in photoshop.

• Gale 09Oct14: Or have a yellow RP in the playback meter (and clip light not on and MP not jammed against it) and red RP in the recording meter (or vice-versa). I also agree the new gradient image must be the same size as the RMS image. But remember Leland may make the clip indicator wider or more prominent.
• Peter 20Oct14: The bigger of the two new meters does indeed have a yellow Recent Peak - this may influence our choice. BTW these images are extremely difficult to capture - so I am loath to have to redo them yet again.
• Gale 21Oct14: IMO the bigger annotated meters look better but the gradient annotated doesn't look good with the stretching. The scale really ought to look as on the RMS Meter. I use IrfanView and Paint.NET (sometimes both on the same image, but neither will cause stretching). I can't see the RP at all in the recording gradient meter. The green/yellow RP is too weak in real life IMHO but if you captured an orange RP it would look much better.
• Peter 21Oct14: Ok I will try and catch one of the orange blighters, but they are difficult to nail down ;-) It's not PowerPoint doing the stretching unbidden, it was me using Powerpoint to do the stretch. I will redo them with the meters stretched natively in Audacity.
• Gale 21Oct14: Try generating a 30s tone amplitude 0.8, silence all but the first 4 seconds, then apply +2 dB gain with the gain slider.

The abbreviations used in the image below are explained in the following text.

• CP: Current Peak Level. The right-hand edge of the darker part of the bar. This shows the current peak level of the audio, and relates directly to the dark blue shading in the waveform.
• RP: Recent Peak Level. These lines indicate the highest peak level attained in the last few seconds. They disappear after playback or recording is stopped, or if you left-click on the recording meters.
• MP: Maximum Peak Level. The blue lines indicate the maximum peak level attained during the current playback or recording session. They remain visible after playback or recording is stopped, and are reset when a new playback or recording session is started, or if you left-click on either of the meters.
• Clip: Clipping warning. The red lines to right of the maximum value of the scale appear as soon as there are four or more consecutive samples of audio exceeding that maximum. Once they have appeared, the clipping lines remain visible throughout that playback or recording session. They are thus not an indication of current clipping, but an absolute indication that clipping occurred somewhere in the track. The lines remain visible after playback or recording is stopped, and are reset when a new playback or recording session is started or if you left-click on the recording meters.

Additionally the RMS Meter has:

• CR: Current RMS Level. The right-hand edge of the lighter part of the bar. This shows the average level of the audio and gives a general indication of its perceived loudness. It relates directly to the amplitude of the light blue shading in the waveform.

To find the exact points where clipping exists in a track, enable View > Show Clipping or run Analyze > Find Clipping....

Meter channels

• When playing a mono track, Audacity sends the output to both left and right speakers. Therefore if you leave the pan slider on the Track Panel untouched, both channels of the playback meter will show an identical level. If you pan towards one channel, then the opposite channel will have its level reduced until a complete pan away from it will remove it.
• If you set Audacity to record in mono (for example, from a microphone), only the left channel recording meter will be active.

Adjusting playback level

The playback level displayed in Meter Toolbar reflects the combined amplitude of all the tracks in your project, in other words, the level of the mix as determined by the gain sliders on each track.

The playback volume slider on Mixer Toolbar does not affect the playback meter - the purpose of the meter is solely to indicate what the loudness of the project audio would be were you to export it as an audio file.

Adjusting and monitoring recording level

Having chosen the correct recording device in Device Toolbar, use the recording volume slider on Mixer Toolbar to adjust the level of audio being recorded. In the image above, note that the blue lines in the recording meter (indicating the maximum peak level attained) are at about -6 dB. This is a sensible level to aim for when recording, because it gives you headroom to make edits affecting volume afterwards.

Note that in some cases the recording volume slider may not be visible, as described on the Mixer Toolbar page. In that case you will need to use your sound card's or operating system's recording/input volume control to set the recording level in Audacity.

Monitoring

It is good practice to test the correct recording level before recording for real. Monitoring lets you do this without actually having to record and then delete a test track. It also verifies that you are recording the input source you expect. There are two ways to turn monitoring on and off:

• Left-click on the recording meter to turn monitoring on. Click again to turn it off.
• Click on the downward-pointing arrow beside the microphone symbol to display the meter drop-down menu. Choose "Start Monitoring" or "Stop Monitoring" as appropriate.

You will probably want to hear the monitored audio as well as see it. To do this:

• on Windows or Linux, unmute the playback of your input source in the playback side of the system mixer. If this does not work, enable "software playthrough" in the Transport Menu
• on Mac OS X, enable "software playthrough" in the Transport Menu. If this does not work, try the free LineIn application.

Undocking and Resizing

Like all toolbars, Meter Toolbar can be undocked, but unlike the other toolbars, it can also be resized. Resizing gives longer scales for the meters and hence a more accurate view of the volume levels.

• If the meter is docked, you can resize it horizontally by clicking and dragging the right edge.
• To undock the meter, click the handle on the left edge and drag. You can drag outside the Audacity project window, too.
• To resize when undocked, click on the resize handle that appears at the bottom right of the toolbar and drag horizontally or vertically.
• When resizing vertically:
  • The meters display one above the other when the toolbar height allows this, but the height is less than the width
  • The meters display in vertical orientation when the toolbar height exceeds its width