Beginner-itis - Saving a chosen portion of an mp3

[Gale Andrews]

If I try to shorten or elongate the length of the piece I'm trying to save by using the line across the top (whatever that line is called) and drag it to the right to elongate the piece it doesn't work.

That line across the top is the Timeline. Dragging selections in the Timeline just makes a temporary selection that plays (and by design, doesn't affect the selection in the blue waveform).

Also consider clicking at the starting point of the audio you want to export then (CTRL + B) to add a label there. Do the same for the ending point. Zoom out so you can see both labels then click as close to above the first label as you can. This should snap the cursor to the label (when this works you will see a yellow line). As soon as you see the pointer, drag to the second label and when you see the yellow line, release the mouse button. Now you have your selection ready to edit or export.

Or another way. Instead of labelling the start and end, add a split line at the start with CTRL + I. Do the same at the end.Then double-click anywhere to left of the ending split line to select between the split lines (no need to zoom out).


Gale

[eager to learn]

Getting to that starting point is no easy feat. I had to slide it back and forth many times. Is there any way to calibrate it with numbers?

Ex. You want the music to start at 2.015 and then end at 3.225

Can you type in these numbers anywhere to grab that section numerically?

Otherwise it takes a lot of work to finally get the first mark exactly right and then the end as well.

I thought that finger is what created the area of sound to be grabbed and then saved?

I'm not clear on the CTRL + B process. Do I place the mouse/cursor in the blue/purple area and then once I hear the exact spot I want to start am I supposed to then immediately hit CTRL + B? Is that what will them mark the beginning if the piece to be saved?

And then when I hear the last note I want at the end ht CTRL + B again to mark the end of the price to be grabbed?

Thanks.

[Gale Andrews]

Getting to that starting point is no easy feat. I had to slide it back and forth many times. Is there any way to calibrate it with numbers?

Ex. You want the music to start at 2.015 and then end at 3.225

Can you type in these numbers anywhere to grab that section numerically?

Yes. Type the numbers in Selection Toolbar.

Right-click over any of the three spinboxes and choose "hh:mm:ss + milliseconds". Type 2.015 in the "Selection Start" spinbox and 3.225 in the "End" spinbox (if the button says "Length", move it to "End").

I thought that finger is what created the area of sound to be grabbed and then saved?

Please read the link Steve gave you http://manual.audacityteam.org/o/man/au ... ction.html .

I'm not clear on the CTRL + B process. Do I place the mouse/cursor in the blue/purple area and then once I hear the exact spot I want to start am I supposed to then immediately hit CTRL + B? Is that what will them mark the beginning if the piece to be saved?

And then when I hear the last note I want at the end ht CTRL + B again to mark the end of the price to be grabbed?

CTRL + B (and CTRL + I) were only suggestions. To add a label at the point you are playing, you have to use CTRL + M. See http://manual.audacityteam.org/o/man/label_tracks.html .

But for what you are describing there is another, easier way. Play the audio. Press [ when you hear the start point. Press ] when you hear the end point. The ] draws a selection between the point in the waveform where you pressed [ and the point in the waveform where you pressed ]. This is in the Manual too ( http://manual.audacityteam.org/o/man/au ... ml#playing ).



Gale

[eager to learn]

Hi Gale,

Using the [ and ] works very well and easily.

I was curious if I wanted to ascertain exactly numerically where that starting point and ending points are all I see are 1 and then hash marks and then 2.

How could I determine the exact numbers if I press the [ at someplace beyond the hash mark so it's farther than 1.25 or 1.5 - maybe it's around 1.38 or 1.69.

Is there some way to determine the precise starting and ending locations numerically for a section "grabbed?"

Thank you so much for all your help and patience.

This is pretty cool!

[Gale Andrews]

I'm not sure what hash mark you are looking at. If you mean the Timeline ( http://manual.audacityteam.org/o/man/timeline.html ), you will have to use the zoom button (or CTRL + 1) to zoom in before the Timeline shows many gradations between seconds.

However if you set Selection Toolbar to hh:mm:ss + milliseconds as I described ( by right-clicking over any of the three spinboxes), then change the middle spinbox in Selection Toolbar to "End", you will be able to read the time of the start and end of the selection you made with [ and ]. The "Start" box will show the time position of the left edge of the selection and the "End" box will show the time position of the right edge of the selection.

If the selection border is not correct, hold SHIFT while pressing LEFT arrow on the keyboard to extend the left edge of the selection further leftwards. Hold SHIFT while pressing RIGHT arrow on the keyboard to extend the right edge of the selection further rightwards

Hold CTRL + SHIFT while pressing LEFT arrow to move the left edge of the selection rightwards (so making the selection smaller). Hold CTRL + SHIFT while pressing RIGHT arrow to move the right edge of the selection rightwards (again, making the selection smaller). See http://manual.audacityteam.org/o/man/au ... l#keyboard .

If preferred, you can move the selection edges using Selection Toolbar just by changing the number in the Start or End spinbox. You don't need to be zoomed in to move a selection edge by just a few milliseconds, but you wont see the selection edge move unless you are zoomed in.



Gale

[eager to learn]

I have a green dot placed inside the circle next to the word End in the middle graphic ooh00m00 - I guess that's one of the 3 spin boxes? But, when I hit play the line goes across playing the music but the numbers in those spin boxes never change in the first or 2nd spin box - they both remain at 00h00m.

When I right click over the middle or first spin box there is a check mark next to hh:mm:ss.

So, it doesn't seem to register any time elapse when the music plays.

I'd like to be able to first determine the exact time the piece begins and ends and then change that by typing in the numbers in the start and end boxes, respectively.

Thank you.

[Gale Andrews]

I have a green dot placed inside the circle next to the word End in the middle graphic ooh00m00 - I guess that's one of the 3 spin boxes?

Yes.

when I hit play the line goes across playing the music but the numbers in those spin boxes never change in the first or 2nd spin box - they both remain at 00h00m.

The Start and End box values do not change unless you click in the waveform, make a selection in the waveform, or modify the digits in the boxes. Modifying the digits in the boxes modifies the length of the selection in the waveform.

To learn how to change the digits in the Start and "End/Length" boxes so as to modify the selected length of audio, click this link in blue http://manual.audacityteam.org/o/man/se ... olbar.html then press the "End" button on your keyboard. Then read "Editing the Selection Toolbar values" near the bottom of that page.

Then I right click over the middle or first spin box there is a check mark next to hh:mm:ss.

I suggest (as I have done already) actually clicking on hh:mm:ss + milliseconds in that right-click menu. This lets you measure time positions (cursor) or selection lengths to the nearest millisecond.

it doesn't seem to register any time elapse when the music plays.

If you click on the link I gave you above ( http://manual.audacityteam.org/o/man/se ... olbar.html ) it explains that only the third box (Audio Position) goes round with playback or recording.

I'd like to be able to first determine the exact time the piece begins and ends and then change that by typing in the numbers in the start and end boxes, respectively.

The piece should begin at time zero. To demonstrate that, click anywhere in the waveform and press J on your keyboard to move the cursor to the start of the track. Observe Selection Start changes to all zero values. Now hold SHIFT on your keyboard while pressing K on your keyboard. This selects from the start to the end of the track.

* The End box now displays the end time of the track.
* If you change the "End" button to "Length", the box will display the length of the track.
* Because you are selecting from time zero to the end of the track, the "End" and "Length" buttons display the same value.




Gale

[eager to learn]

I think I'm getting a better idea of this. I read over the link again.

If in the blue/purple area = waveform, I place the cursor and press J it takes everything to the very beginning of the piece captured.

Then, when I hold SHIFT and press K it takes it to the the end of the piece captured and in the hh:mm:ss - whatever that area or function is called it shows End: 14 seconds.

So, if I wanted to shave off any time at the end could I just go into that hh:mm:ss and type in say 12 or 11 to replace that 14?

I'm not clear how I could shave any time off the *beginning* of the piece since it starts at hh:00:mm:00ss:00?

Also, does Project Rate change how fast/slow the piece will be be saved as? Ex. RPM – revolutions per minute – so you can change how fast a piece will be played as saved if you wanted to accelerate or decelerate how fast a recording will be heard?

Thank you.

[Gale Andrews]

I think I'm getting a better idea of this. I read over the link again.

If in the blue/purple area = waveform, I place the cursor and press J it takes everything to the very beginning of the piece captured.

Then, when I hold SHIFT and press K it takes it to the the end of the piece captured and in the hh:mm:ss - whatever that area or function is called it shows End: 14 seconds.

So, if I wanted to shave off any time at the end could I just go into that hh:mm:ss and type in say 12 or 11 to replace that 14?

Type 12 where the 14 is and the selection will then be from time zero to 12 seconds, because you told Audacity the end (or the length) was 12 seconds.

Why not try it out? You will learn quicker by experimenting.

I'm not clear how I could shave any time off the *beginning* of the piece since it starts at hh:00:mm:00ss:00?

Replace the zero or zeros in Selection Start with the time you want the selection to start at. For example, if you want the selection to start at 5 seconds, type 5 in the last zero in Selection Start.

If the selection at the end of the waveform jumps past the end, this will be because you have the End/Length button set to "Length". If you had it set to a "Length" of 12, then with a Start of 5 the end of the selection in the track would move to 17 seconds (5 +12). So if the end of the selection jumps past the end of the waveform, just set the "End/Length" button back to "End", and change 17 back to 12.

Also, does Project Rate change how fast/slow the piece will be be saved as? Ex. RPM – revolutions per minute – so you can change how fast a piece will be played as saved if you wanted to accelerate or decelerate how fast a recording will be heard?

Project Rate controls the "sample rate" of the audio - see http://manual.audacityteam.org/o/man/gl ... ample_rate .

Sample rate can be thought of as the "density" of audio samples. The more samples there are per second (the higher the sample rate in Hz), the higher the frequencies the audio can contain. Changing the sample rate in Project Rate does not affect the length or the speed, only the quality. It makes there be more samples or fewer samples in the same length.

You should leave the project rate at 44100 Hz for most cases, but as an experiment, import some high quality audio, change project rate to 8000 Hz then play the audio. Just playing won't change the audio data, but it will be resampled just for playback as if there were only 8000 samples for each second of audio instead of 44100 samples per second. As a result, the audio will sound "dull" because the high frequencies cannot be represented with so many fewer samples of audio.

You can change the speed of the audio by "Set Rate" in Track Drop Down Menu ( http://manual.audacityteam.org/o/man/tr ... l#Set_Rate ) . This does not change the number of samples in the selection, and so it necessarily changes the length and the speed of the audio. Whatever number of samples are there already are packed into a smaller space (so play quicker) if you increase the rate, or are expanded into a larger space (so play slower) if you reduce the rate.



Gale