Audio loop Clicks + Sonar 8 update

Do you have 'Snap to Audio Zero Crossings 'checked - click on the down arrow next to the snap to grid icon

Usually if there is a pop it's because it's not at zero

Are your loops definitely at zero?

We need CJ on the case

I had this and I'm sure it was the snap to grid thing he suggested.
They looked alright to the naked eye but obviously they were not.

Yeah normally you just ask a question

And he appears

I asked - Also, if I record a loop of say 8 bars, when it finishes and restarts it's like as if you're flicking on a switch - as if the audio was switched off and back on again. Basically, it's a tiny pop I suppose - at the start and not the end.

CJ replied - Are your loop points at exactly 8 bars?? Did you enable it with the snap to grid activated??

Ben,
If you recorded in loop mode, this may be relevant: zoom way in on the end of the loop and see if there is a gap. If so, you are experiencing a bug in ASIO mode that has been there a while. Please add your bug report.
Bill B.

Do other loops make a pop or only ones you have created?

It's been my experience that all audio edit operations that are based on the time bar operate purely on musical or absolute time setting and will ignore the zero-crossings snap setting. This includes copying a range, the transport loop controls, loop recording, etc. Sorta makes sense because time bar edits affect multiple tracks and the concept of zero-crossing doesn't apply.

To loop audio without clicks, you have to cut the source audio by clicking in the audio track to set the start point then ALT-dragging to the end of the section you want to loop. Sonar will select the begin/end points at zero-crossings (if you've got zero-crossing snap set). This selection can be used as click-free source material for your loops.

Ben, I don't know if this is the cause of your problem, but it's worth pointing out. If this doesn't help and you're still having trouble, it would be good for you to describe your exact process for recording and looping.

Murray

Hi Murray,

im sorry but i dont understand your explanation on "to loop audio without clicks" when you say "cut the source audio by clicking in the audio track to set the start point"........i dont get this........surely if you are looping something i type the exact nuber into the loop section on the tool bar.

"then ALT-dragging to the end of the section you want to loop" im sorry i dont get this either, do you mean the ALT button on the computer keyboard ? as this does nothing for me, if i drag any audio it either dissappears if i click right on the edge of it or just moves the section of audio along if i click in the middle.

My Process for recording and looping....

1. For example i want to loop a 4 bar chord sequence on guitar.
2. set the metronome for the speed i want
3. hit record
4. play the 4 bar chord sequence a few times in time with the metronone
5. stop recording
6. click on the loop section on the tool bar
7. select the start loop point for example 1:01:000
8. select the end loop point for example 5:01:000
9. listen to the loop, and get an annoying pop/click sound at the start of the loop and everytime it is repeated it pops/clicks
10. then i get fed up....haha

hope this helps if im doing something wrong to explain what im doing

Ben

Ben,

Thanks for detailing your process because it shows why you are getting clicks.

The basic problem is the way that you are defining your loop. In this case, you're defining the loop using start and end points in musical time. Because this is a time bar function which applies to all tracks, as opposed to an audio track function which applies to a single track (my terminology, but I've not seen a better explanation in any documentation...) the zero-crossings are not being examined by Sonar when it sets the boundaries of your loop. Unless you are really lucky, you'll get clicks at the start and end points.

So the answer to your first question is that the loop section in the tool bar doesn't observe zero-crossings in tracks and will cause clicks:

im sorry but i dont understand your explanation on "to loop audio without clicks" when you say "cut the source audio by clicking in the audio track to set the start point"........i dont get this........surely if you are looping something i type the exact nuber into the loop section on the tool bar.

Your second question is about how to do the track editing:

"then ALT-dragging to the end of the section you want to loop" im sorry i dont get this either, do you mean the ALT button on the computer keyboard ? as this does nothing for me, if i drag any audio it either dissappears if i click right on the edge of it or just moves the section of audio along if i click in the middle.

What you are going to do is to select your audio from the recorded audio track, paste it in to a clean audio track, then loop it. This is a little tricky because you have to get the click/key/drag/release order right. Select the track by pressing & holding the ALT key on your PC's keyboard and clicking in the track controls to the left of the audio then click in the audio waveform at your start point. Don't release the mouse button or ALT key. You should see a vertical cursor in your audio. Now select the remainder of the loop and dragging the cursor to the right. Release the mouse button when you reach the end of your loop. You should see your loop in a dark color, meaning that it is selected. If not, go back and try it again until you get it right.

(For grins and to get more comfortable with this process, you can zoom in down to the waveform level and you'll see that the cursor always snaps to a zero crossing when you click on the audio in a selected track but doesn't when you set the cursor in the time bar.)

Next, copy the selection with control-C, then paste it into a clean track with control-V. You can drag the new clip edge to loop it. Mute the original track and playback your new looped track.

There are other ways of doing this. You could click at start point and split the track, then delete the lead-in. Same-o for the end point. Ususally when I post my workflow, someone chimes in with a better way which is always fine with me.

The big take-away from this post is that snap to zero-crossings works only when editing a single track.

Hope this helps.

Murray

Edit: Had the Alt key order wrong.

There's one other thing that you should be aware of, but it's hard to explain without a picture. Not knowing your technical knowledge, I'll give you a long-winded explanation.

Imagine that your loop is a sine wave. It starts at zero, goes up, flattens out, comes back down to zero, goes down, then finally turns up and returns to zero. This is one cycle and it repeats for the duration of your loop. When Sonar snaps to a zero crossing, it can snap to a zero where the wave is going up or where the wave is going down. If the audio you select starts with the wave going up from zero and ends where the wave comes down to zero, there will be a click. This is because the wave abruptly changes direction at the loop points: it comes down to zero then changes direction and goes back up. This abrupt change in direction has high frequency content that sounds like a click.

So there's one more step that I should have mentioned. After you paste your loop selection into the new track (and before you loop it), zoom in down to the waveform level at the start point and see if it is going up or down from zero. Then look at the end of the loop. The directions should be such that the waveform doesn't abruptly change the direction that it was going in at the end of the loop when it starts at the beginning of the next: i.e., the beginning and ending directions should be the same. I always have the beginning start at zero and go up and make the ending approach zero from below.

Hopefully I didn't lose you in all the words. Visually it's simple to see.

It is tricky if you need to cut off a half-cycle. Bring up the snap settings window and select Absolute Time with 1 sample resolution. (No need to close the window.) Click on the zero-crossing and split the clip, and discard the half-cycle you don't want. Be sure to change your snap settings back to whatever music time you use.

Whew. Next time this topic comes up, let's solve it on WebEx.