Resetting downbeat in middle of song

[Homina]

There's a song from 1970 entitled "Ride Captain Ride" by the Blues Image. I'm interested in re-creating this song. After loading it into Logic 10.6.1 using "Adapt Tempo," inspecting its tempo map, and setting the downbeat accurately, I saw that the song's downbeat changes between measures 55-56, about 1:48 or halfway into the song. The group executes a little flourish there to change the tone of the song for eight measures before resuming its initial cadence. From that point on the downbeat of this 4/4 song is displaced by two beats for the remainder of the song. With live musicians this kind of thing wouldn't even introduce a burble into performing it. With a computer's AI it's a different story. I cannot figure out how to alter the song's downbeat midway through it. I'm not even sure it can be done. If anyone has an insight into how I might make this work, I'd appreciate hearing it. Thanks.

[Zipfunk]

Import your song in Adapt mode, then switch to Keep Tempo.

Find where the discrepancy in the beats starts and add or subtract a bar of 2/4 and that should get you back on track.

(you could also add a time signature of 6/4 for one bar, then switch it back to 4/4)

I just did it with a song to double check the method (as I've not come across this issue before)

 

Drew

[Homina]

I appreciate the suggestion. Thanks.

 

A most curious thing. Implementing your 6/4 back to 4/4 idea does indeed move the metronome's differential polyphonic downbeat to where it should be after the flourish that changed it. It does NOT, however, change the downbeat as shown in the Smart Tempo editor, which is where I altered the downbeat in the first place. The two appear to be divorced one from the other WRT downbeat emphasis.

[MikeRobinson]

In "musical notation" parlance this would be a time signature change: one or more "6/4" measures are inserted into a "4/4" song.

[Homina]

You are correct; the suggested change was a time signature alteration. Nothing was inserted, however. I simply assigned six beats of the song a different time signature than before, and then reapplied the original time signature to the remainder. The net effect was to restore the downbeat - at least audibly via the metronome - where it belongs in the last half of the song. The odd thing is that this change is not reflected in the Smart Tempo window, which still shows the downbeats after the 6/4 alteration in the same positions as before, two beats away from where they should be.

[triplets]

Can you take a screenshot of the issue?

[Homina]

Arrange shows 6/4 at playhead. Smart Tempo shows 4/4 at playhead. Arrange is correct; Smart Tempo is not. After 4/4 is reinstated audible downbeat is correct, but it does not occur on the downbeat shown in Smart Tempo.

[triplets]

Don't know if smart tempo is smart enough to handle correct time signature changes.

[Homina]

Judging by this example Smart Tempo and the Arrange section appear to function independently WRT time signatures.

[David Nahmani]

Arrange shows 6/4 at playhead. Smart Tempo shows 4/4 at playhead.

The playheads are not in the same positions in both panes.

[Homina]

Good observation. The significance of the playhead discrepancy, however, is not clear. The video attached to this message shows both the Tracks/Arrange and Smart Tempo displays as the playhead moves into, through, and past the 6/4 section. As you can see the Tracks/Arrange window shows 6/4 when the section begins and displays 4/4 after exiting the 6/4 section; Smart Tempo displays 4/4 throughout. Also note that the windows' playhead positions are not the same during playback, which accounts for why they're different in the screenshot posted earlier. As to why they're different, I don't pretend to know.

Sigs1.mp4.zip

Edited May 4, 2021 by Homina

[David Nahmani]

The Smart Tempo editor and the Tracks area are independent. You currently have Catch turned on in the Smart Tempo editor which is why you see the playhead move there at the same time as it does in the Tracks area.

 

The Smart Tempo editor has its own ruler, it own time signature and tempo values (independent of the main ruler). The Smart Tempo ruler starts at the beginning of the audio file.

 

Note the unsync'ed playheads, and different bar number and tempo values in the animation below:

 

[Homina]

I don't dispute anything you say. In light of it I can't help but wonder why you brought up the playhead discrepancy in the previously posted JPG.

 

Evidently I can change time signatures within an audio file, such changes can alter the song's downbeat, and therefore the metronome's downbeat click. Those changes are not reflected in the Smart Tempo display, however. I understand that Smart Tempo is a specialized capability, and I'm grateful it's part of Logic. The reasoning behind how Logic implements things, however, has occasionally eluded me, as in this case.

[David Nahmani]

I don't dispute anything you say. In light of it I can't help but wonder why you brought up the playhead discrepancy in the previously posted JPG

I may have answered a little too quickly. I thought you may have applied your region tempo to the project tempo and were expecting to see the same tempo changes and time signature changes in the same places. I wanted to point out that because your playheads weren't in the same measures, you shouldn't expect to see the same tempo information.

 

Evidently I can change time signatures within an audio file, such changes can alter the song's downbeat, and therefore the metronome's downbeat click. Those changes are not reflected in the Smart Tempo display, however.

If you make time signature changes in the Tracks area then they affect the playback of the metronome but are not visible in the Smart Tempo editor. If you make time signature changes in the audio file then they are shown in the Smart Tempo editor. If you then apply region tempo to project tempo then you're committing your Smart Tempo edits to the project tempo and you can hear the metronome follow.

 

The Smart Tempo editor shows you beat marker positions inside the audio file, along with the tempo and time signature change data embedded inside the audio file. The Tracks area shows you project tempo and project time signature changes. Imagine recording a 2 bar drum loop, in the Smart Tempo editor you'll see bar 1 and bar 2, but you might want to use that loop at bar 9 and loop it 12 times for example.

 

There are various methods for transferring the beat position/tempo/signature data from the project to an audio file or from an audio file to the project, but that data is not necessarily always synced between the Tracks area and the Smart Tempo editor.

 

In your case the best would probably be to first work in the Smart Tempo editor, do all your tempo AND beat position AND time signature changes there until the metronome when playing back the Smart Tempo editor is in sync with the audio file. Once you're happy, choose Edit > Apply Region Tempo to Project Tempo.

[David Nahmani]

I suppose a moving picture is worth a million words. Here's an example. One bar of 3/4, then one bar of 4/4 at a fast tempo, then one bar of 3/4. Hope that clarifies the process? Let me know if you have any questions!

 

[Homina]

Maybe I'm missing something, but I can't seem to accomplish everything I want just working in the Smart Tempo window.

 

Changing time signatures in Smart Tempo does display corrected downbeats judging by their visual placement in the Smart Tempo window. However, such changes do not alter the downbeat in the metronome click, which remains audibly two-beats away from where it ought to be after the lone 6/4 section is past. If I only change things in the Smart Tempo window and can't introduce changes to the metronome click from there, then things will never be in sync with the song's downbeats. To make them coincident I also have to make the same changes in the audio file in the Tracks area. If that's what I need to do, OK. Nonetheless, it seems illogical that changes made in one place do not produce observable effects elsewhere. After all, both the Tracks and Smart Tempo windows are working with the same audio file.

[David Nahmani]

Maybe I'm missing something, but I can't seem to accomplish everything I want just working in the Smart Tempo window.

Correct. Once you're done working in the Smart Tempo editor, you have to transfer your data to the project by choosing Edit > Apply Region Tempo to Project Tempo. That's what I do at the end of my video (perhaps you missed it? Here it is : viewtopic.php?f=1&t=157322&p=825069#p825062)

 

Changing time signatures in Smart Tempo does display corrected downbeats judging by their visual placement in the Smart Tempo window. However, such changes do not alter the downbeat in the metronome click

Edits in the Smart Tempo editor affect the metronome in the Smart Tempo editor, not the metronome in the main project, not until you've transferred your data to the main project.

 

Nonetheless, it seems illogical that changes made in one place do not produce observable effects elsewhere. After all, both the Tracks and Smart Tempo windows are working with the same audio file.

Maybe in your present situation, but it's not always that simple. The Smart Tempo editor has to accommodate for audio files that may be used in multiple places in your project. Or when you're using only a portion of an audio file in your project. Or perhaps you're using a small portion in one place and another portion in another section of your project. Or perhaps your project uses multiple audio files on different tracks and those audio files don't all have the same downbeat/tempo/signature data embedded.

 

That's why things aren't simply hard-synced between the Smart Tempo editor and the Tracks area, and that's why you are given the flexility to determine which data you want or don't want to transfer from the Smart Editor to the project.

[Homina]

That makes sense. I'm using Smart Tempo to establish overall timing from a single audio track. Subsequent tracks will have to conform to the beat track thus created.

 

Someone using multiple files to produce the same outcome will not be able to follow the same steps. In that pursuit having Smart Tempo function independently would obviously be invaluable.

 

What irks me is how instantly complex things become whenever AI is involved. A garage band playing this song might not even notice the unconventional change in the middle. For all practical purposes they'd adapt to it unconsciously, as I'm confident the original band did. Trying to bring the song into a DAW, however, requires some gymnastics, and until they're done to the AI's satisfaction, it ain't happening. All I wanted to do was move downbeat emphasis two-beats after a certain point in a song, and look at what it took to get that done. Just another example of fundamental analog-digital incongruity, like human musicians having to follow a click-track; it just isn't natural.

 

Thanks for all the input.

[David Nahmani]

Like many processes, I find the learning/understanding of the tool to be unnatural. There's a learning curve. You have to make sense of how it works, and in the process you're inevitably going to wonder who decided to build the tool that way and why?

 

However like many things in life (including, say, riding a bike), while your first approach may be a discouraging battle, that comes with the inevitable feeling of sometimes wanting to give up, if you chose to take on the challenge until you master the tool, then you'll be rewarded with great joy and feelings of freedom, of being able to go wherever you want with ease. And like when riding a bike, once the craft mastered, you will forget the tool, and focus on the musical goal only, sometimes even left wondering what you may have found so complicated in the first place.

 

But yes, you're likely to hurt your knees and perhaps even bleed a little in the process.

 

[Homina]

I'm a testament to the validity of what you say. All of my worthwhile accomplishments were gained via the path you outlined. My knees show the attendant scars.

 

That doesn't mean I didn't vent along the way, though...

[Big Joseph Warrior]

I looked far and wide to even find a discussion on this topic - altering the downbeat partway through a song. I am attempting to do the same thing with an original recording, imported into Logic. The recording was done 15 years ago, and without a metronome. Logic can track the first half of the song with Adapt Tempo wonderfully. However, it does not understand how to adjust when the song intentionally switches gears mid-way through a measure. It's not even the tempo that changes, but the placement of the downbeat. When I gave Logic a downbeat suggestion at this point in the timeline, it went on recursively to disrupt the perfect Adapt Tempo markers that I did not want changed (all tempo markers prior to the downbeat change.) Is there a way that someone would be willing to assist over Facetime? I have read with earnest the comments up to this point. However a clear understanding of exactly how to accomplish this hasn't clicked. Any help would be so much appreciated.

[wonshu]

Sounds like you have to just manually beatmap from left to right.

There's a thread here somewhere explaining exactly how to do beatmapping. Please search for it.

[Big Joseph Warrior]

On 3/27/2024 at 5:26 AM, wonshu said:

There's a thread here somewhere explaining exactly how to do beat mapping. Please search for it.

Thanks! I tried to find it, but without success. Possibly due to my inexperience using forums? Would you please post a link to the thread you are referring to?

[wonshu]

This is also a good place to start learning about beatmapping:

https://support.apple.com/en-gb/guide/logicpro/lgcp6338b8d1/mac

[David Nahmani]

10 hours ago, Big Joseph Warrior said:

I tried to find it, but without success.

Here's one topic that should help: 

You can also try a search for the beat mapping tag.