Coming Attractions

jeff

Based on recent conversations here, I've decided to take a long hard look at all things related to synchronization, alignment, and quantization. There are a number of deficiencies around these that we've been hitting for some time,
and the way we work around these is complicated and often require scripts. This will be the development focus for the next few weeks.

It will be phased in gradually with the first phase involving Quantization.

Quantization is all about "when things happen". Do you want something to happen now, or at a point in the future? There are currently four options for quantization:

  Off
  Subcycle
  Cycle
  Loop

Off means there is no quantization and the action you are requesting happens immediately. The other three are local quantization points. They are called local because they are "inside" the loop you working with. Loops have always been divided into some number of cycles and subcycles depending on how they were recorded. The meaning
of those divisions was always rather fuzzy. A cycle may be the same as a bar in music notation, but it is often much larger than that. Similarly, subcycles may represent a beat or a bar or something in between. Loops don't really have a time signature.

By far the most common quantization point is Loop. It is easy to understand, it is simply the start/end of the loop. The others, especially cycle are harder to predict because they get generated automatically as a side effect of recording and other actions like InstantMultiply or Insert. I'm not going to talk about this yet, but I'll be looking
at other ways to organize these arbitrary subdivisions of the loop. More control over what a cycle actually means and how many of them there are. A word you will start seeing more is Marker.

A marker is just a point in the loop. Subcycles and cycles are just markers that get thrown in automatically. But you should be able to move those around and drop markers wherever you want. How exactly you do that while performing live is the big question. More on that later. You will start seeing Marker appearing in the list of local quantization points.

When we're thinking about timing below the level of the loop point, we usually have a tempo and a time signature in mind. It may just be something you had in your mind as you were recording that 12 second loop, or more often you are synchronizing to something like the Host Transport, or MIDI clocks from a drum machine. How we think about synchronization in Mobius is also going to be changing quite significantly. I won't discuss that yet, but you will be seeing these new words appearing when you select quantization points.

  Sync Start
  Sync Beat
  Sync Bar

We've had those before in the parts that dealt with synchronization. What's new is that these are now available as quantization points. As a simple example, if you want to turn Mute on at the next host transport bar, set the quantization point to Sync Bar. It does not matter where the loop's cycles or subcycles are. These are called external quantization points. They are external because they live "outside" the loop.

This is where the concepts of quantization and synchronization start to melt together. You're not waiting for a location within the loop itself, you're waiting for something else to reach a location. But they're really doing the same thing: waiting. It may take 1.372 seconds to reach the next local subcycle or it may take 2.592 seconds to reach the next host bar. Where those numbers came from doesn't really matter, you want to wait x seconds, then do a Mute.

So we can wait for local points within the loop, or we can wait for something in the Host transport. What else might we wait on? How about other tracks? You will see these words appear in the list of quantization points to select.

  Leader Subcycle
  Leader Cycle
  Leader Loop
  Leader Marker

We have had two different concepts where one track would pay attention to another track: The Track Sync Master which was used for synchronized recordings, and the MIDI Track Leader which was used for all sorts of messy things.

The concept of a track being a leader or follower is going to be generalized so that it applies to both audio and MIDI tracks. Once you have a leader/follower relationship, you can use that for many things. A follower may choose to respond to something that happens in the leader, and the leader may choose to tell its followers to do something.

There is usually one Default Leader, which is the same as what we currently call the Track Sync Master. The phrase "Track Sync Master" never really rolled off the tongue very well, so I'm going to start calling that just "The Leader" (or maybe "Dear Leader"). Like the current TrackSyncMaster, you can elect any track to be the leader, and if there is no current leader, a track may appoint itself as the leader. All tracks have the option of following this de facto leader.

Some tracks though may have their own ideas. They live in a bunker in northern Idaho and distrust elected leadership. They will follow track number 5 until you pry it from their cold dead hands. Any track may declare its allegiance to another track and will ignore the default leader.

So what does all this nonsense have to do with quantization?

Once you have established a leader/follower relationship between two tracks, the follower may use points in the leader as quantization points for its own purposes. If you used this leader track to synchronize the recording of the follower, then the leader subcycle/cycle/loop points may already align with those same points in the follower. But they don't have to.

[Cue the cinematic trailer music] "Imagine a world, where the leader track contained only markers".

Marker tracks contain sequences of markers. Markers are just moments in time. They don't do anything
but they can have names like "Intro", "Verse", "Chorus", or "Steve". Since marker tracks don't contain anything complicated, like sound, they can be stretched or compressed to fit any expanse of time.

But I'm getting ahead of myself.

TL;DR WTF does any of this mean?

In addition to the current quantization points subcycle, cycle, and loop, you can now quantize against
the sync source (start, beat, bar) as well as points in another "leader" track.

The End

trevorn1

jeff this is really interesting and I'm really curious to try this out. I think this very clearly solves something that I've always wanted to try to do with changing to different synced or asynchronous elements. Really heady and cool.

steveg

jeff
https://youtu.be/0B61_5sRoBI?si=sGeEIbNvF2QEMNEj

alexs1

I'm all for these "external" quantization points. As I understand it, I would be able to quantize a Start and Stop with Host Bar/Beat, for example? Would these new Markers also figure into the binding panel and Configuration Options, i.e., anywhere where the conventional sync params currently live?

I like the Leader/Follower dynamic, it sounds like it should simplify syncronization mechanics between MIDI and Audio tracks nicely.

I remember in another post we were discussing wrapping all different sync sources under the Transport umbrella. Is this on the horizon in the coming attractions? Or would that screw too much with the new Marker DLC?

jeff

alexs1

I'm all for these "external" quantization points. As I understand it, I would be able to quantize
a Start and Stop with Host Bar/Beat, for example?

Yes, this builds on top of the quantization control that went in over the past few releases. You can have Start and Stop use different quantization, and they can use these new quantization points. So in a script or binding:

   Stop(quantize=:off)
   
   Start(quantize=:bar)

Would these new Markers also figure into the binding panel and Configuration Options, i.e.,
anywhere where the conventional sync params currently live?

Markers at least initially would be mostly for quantization points. So you could start a recording on a marker, but markers do not define the unit length of the recording. To get a synchronized recording, it has to be a multiple of some fundamantal unit length: a beat, a bar, that loop over there.

Markers are more random, the distance between two markers isn't necessarily a multiple of a host
beat, or a loop subcycle for example. It would be an interesting thing to explore though.

I remember in another post we were discussing wrapping all different sync sources under the
Transport umbrella. Is this on the horizon in the coming attractions? Or would that screw
too much with the new Marker DLC?

Yes, The Synchronizer is the Transport and can be thought of as the synchronization "hub". Anything you do that you think of as record synchronization is either done against the Synchronizer/Transport or another track.

The Synchronizer can however be controlled by other things. If you make the Synchronizer be controlled by the Host, the Synchronizer will effectively mirror what the host transport is doing. If the Synchronizer is controlled by an external MIDI stream, it will look like whatever the drum machine is doing.

So for the most part, when you configure things or write scripts you don't have to think about host, or
MIDI, or Ableton Link, or anything we might add in the future. There is only the Synchronizer giving you a tempo, beats and bars, and where it got those doesn't matter.

What I think is a misunderstood feature, because it is documented so poorly, is what happens when you make a track be the Transport/Synchronizer Master. In this case the Synchronizer isn't freewheeling at it's own tempo, or getting a tempo from the Host, it is being given a tempo that matches a track.

This is the foundation for what Mobius 2 used to call "out sync". You freely record a track that is however many seconds long. That goes through a tempo analysis/guessing phase that decides "this track looks like it's at 124.2 bpm". If then takes that tempo and generates MIDI clocks that can be sent to a drum machine. So you record a loop starting and stopping anywhere you want, and as soon as you end that recording, the drum machine kicks in at (hopefully) exactly the right tempo to match the loop you just recorded.

This is that "first loop capability" that a lot of loopers don't have. You're not locked into a pre-defined tempo, you get to define the tempo by freely recording that first loop on the fly.

So far this is nothing new. What Mobius 3 adds is that this thing that (can be) generating the MIDI clocks can also be made to look just like a host transport. You gave it a tempo, just layer a time signature on top of that and now you've got beats, bars, and a start point. You can use those those things for quantization and record synchronization just like you would if you were syncing with a host.

I don't think this part has ever been clear, so I'll emphasize this. When a track is the Synchronization Master, it is defining the tempo for the Synchronizer. When you then sync with the Synchronizer, it is exactly the same as using "track sync". The difference is that you have a set of smaller and more musically useful sync units to deal with: beats and bars.

Your master track may be a minute long. What does a "subcycle" even mean? It certainly isn't a "beat". When you freely record a long loop you probably had a pattern in your mind like, "I'm going to record a 12 bar blues at around 90 bpm". Mobius doesn't know any of this. When you're done all it can say is "welp, here is 1 cycle and you asked for 4 subcycles so here they are". Those 4 arbitrary subdivisions are not likely to be useful for anything. What you might want to do next is start recording other tracks that deal with smaller units of time: those "bars" you had in your mind when you made that 1 minute recording. Where are those? They're not subcycles.

The kind of analysis that has to be performed on a long loop to guess where "bars" are is exactly the same as what happens when you try to generate a usable MIDI clock tempo to send to a drum machine. Beat length has to be calculated based on the total length of the recording you made at the moment, not some arbitrary number 4 that's probably been stuck there since you installed the software.

So that is the purpose of the Transport/Synchronizer. It isn't like other loopers or hosts where it forces you into a pre-defined tempo, it is a tempo analyzer that takes an arbitrary span of time and tries to guess what the most appropriate tempo should be. And once it does that, it can tell you where beats and bars are within that span of time. It may not do a very good job of that, there are certainly improvements that need to be made. But it is almost always better than using Cycles and Subcycles when you're starting from long loops.

jeff

I wrote this before I saw the recent comments. I'll address those later, but I think this touches on some of the questions...

Phase 2 Recording

When you go about recording a new loop, there three major things to think about.

  * When does it start
  * How long does it last
  * How does the result align with other things

These are the Three Pillars of Recording if you will: Start, Length, and Alignment.

The current model for synchronized recording kind of mushes these together, and Alignment is difficult to achieve without careful control over both Start and Length.

The new model makes a clear distinction between these phases.

Start is basically just a form of quantization and is independent of length and alignment. I want to start reocrding immediately, or after a threshold, or start on the next host bar. This is controlled by the Record Start parameter with these options:

  Immediate
  Threshold

  Sync Start
  Sync Beat
  Sync Bar

  Leader Subcycle
  Leader Cycle
  Leader Loop
  Leader Marker

Deciding when to begin recording doesn't mean you are going to create a synchronized recording, it just says when recording starts. A synchronized recording is one in which the length has been controlled so that it will fit exactly within something else. This is controlled with the Record Unit parameter which has these options.

  None

  Sync Beat
  Sync Bar
  Sync Loop

  Leader Subcycle
  Leader Cycle
  Leader Loop

None means that there is no defined recording length. You get a "free" recording that will go on until you push a button and end exactly at that time. This loop is not synchronized with anything, but it may serve as a synchronization or quantization source for other tracks.

The three Sync options are recording lengths that are defined by the Central Synchronizer (bonus points if you get that reference). This is the internal component that is currently called the Transport but I think I'm going to change the name to better reflect what it does. It is a provider of synchronization pulses and units that proceed at a certain tempo and time signature. It may in turn be controlled by the Host, a stream of MIDI clocks, or another track.

Tracks don't "sync with the host" any more. They either sync with the Synchronizer or a leader track. If they use the Synchronizer, and the Synchronizer is connected to the Host, then you are effectively using "host sync" but indirectly.

The Leader options are the same as what is now called "track sync". You are letting another track decide how long the recording will last. This may be the Default Leader (formerly TrackSyncMaster) or it may be any other track specified by name or number.

So we've got the recording started, and we've defined how long it is going to be. What about alignment?

It should be clear that if Record Start is Immediate but Record Unit is Sync Bar you're not going to end up with something you want to use. It is still technically synchronized to the host bar, and will play together with the host transport without drifting part, but the "downbeat" or "start point" of the loop is at some random location within the host bar. If you ever Stop and Restart this loop, what it plays will not line up with what the host is playing.

This is exactly the same problem we have with NextLoop+Record or NextLoop with EmptyLoopAction=Record. You can control how long the recording is, but if you didn't also control when it started, the loop will be out of alignment.

The alignment options I'm working on are all new, and I hope will make it "just work". You can start recording any time you want, and end it any time you want. The result will be rounded off and padded so that what you played will always line up with where the host was at that time. It's hard to describe without many, many words so I'll leave it at that. But the goal here is that post-recording alignment, loop switch alignment, that weird "empty switch quantize" option, going in and out of Pause mode, and several other things, all happen automatically and instantly. You can deliberately throw things out of alignment if you want that as an effect, but most of the time Realign is just something that happens and you don't have to think about it.

alexs1

jeff the Central Synchronizer (bonus points if you get that reference).

I like to call it the Suprachiasmatic Nucleus 🧐

jeff

"Would these new Markers also figure into the binding panel and Configuration Options, i.e.,
anywhere where the conventional sync params currently live?"

I think I didn't fully answer this. When a quantization point is Marker or Leader Marker, what that means is "the next marker from where I am now". Unless you say otherwise, markers are like subcycles, you don't pick which one you want, you just wait for the next one.

If you give markers names though, then you can (eventually) do interesting things with them. Rather than this:

      Start(quantize=:leaderMarker)

You could do this:

   Start(quantize=:leaderMarker marker="Chorus")

I may try to get ambitious and put marker names in the same namespace as the built-in quantization points you could write:

  Start(quantize="Chorus")

The quantize value becomes more like a search key than the name of a pre-defined point. In the binding UI, marker names would just appear in the same drop-down menu as Subcycle and Sync Bar so you have only one thing to specify.

jeff

steveg Oh! That's a good one too. But no, this is it... https://www.youtube.com/watch?v=IgG8dxifHfc

steveg

jeff
heh! Love that! Big fan since 1974 when I could first understand what he was saying - Absolutely Free, 200 Motels Hot Rats, etc., etc., No bonus for me