Metropolix Mod Lane Sync

On page 128 of the Metropolix manual in regards to Mod Lanes it states that:

“With ‘ Ramp,’ the ramp time changes with the number of pulses in a stage.
For example, if a stage has 4 pulses, then the voltage will take a full 4 pulses
to reach the assigned MOD Voltage.”

I’ve been trying to figure out how to make a Mod Lane stage have more than one pulse per stage, but so far I only see it moving forward at every single pulse. How is it possible to increase the pulses per Mod stage like it says in the manual as I noted in the quotation above?

Ultimately I’m trying to figure out how to synchronize a Mod Lane’s stages to either Track 1 or Track 2 - similar to how the Track CV Lanes automatically synchronize to the Track.

I don’t see an option for it to automatically synchronize, but is there a manual way to do it that I’m overlooking?

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Being able to lock a mod lane’s stage to the stage of one of the tracks is something I’ve been wanting basically since I got the Metropolix. It would really allow you to do sooooooo much.

So there is no way to manually make a Mod Lane match up pulses with Track Lanes? Is the manual incorrect for noting a Mod Lane can have 4 pulses in a stage?

You can not set the pulse count per-stage on mod lanes, but a stage will be 4 clock pulses long when the clock div on the mod lane is set to /4. I’ll look to see if we can clarify that line.

There is a variety of reasons that the mod lanes are not connected to the tracks, they’ve been discussed in the main thread;

The overall issue is that the mod lanes need to be advanced and have their values extracted before the tracks are advanced and process. If a mod lane changes anything that affects timing, pulse, or stage number (play order, skips, pulse count, etc.) then it just devolves into an endless loop. In another example, if you attach a mod lane to track 2, that modulates track 1, but track one is processed before Track 2, then the modulation will happen late. So, Mod Lanes are simpler (for UI and understanding) and independent (for technical reasons).

Syncing a mod lane to a track would essentially be per-stage values for that parameter, many of the values are already per-stage.

Ah ok, thank you for the clarification. Wouldn’t it be possible to have an option to sync Mod Lanes to the Track Lanes, and when choosing that option, it would just disable all the Mod Destinations that would cause the conflicting problems you mentioned? And then only the non-conflicting destinations are allowed to be chosen?

I know technically you could do this by taking a CV lane from one of the Tracks, directing it out either the A or B output and then just self patch back into X,Y, or Z inputs, but it would be nice to have A and B outs freed up to patch to other external modules and use the Mod Lanes internally synced up.

Currently the unpredictability of all 8 Mod Lanes not synced can be cool if you like this pseudo-randomness all the time, but I think it would be awesome to have some more deliberate predictable modulations through these 8 lanes.

Like you noted, yeah a lot of these destinations are already available per stage, but it’d be a big plus to have all the other ones that aren’t to be able to be synced.

Regarding randomness, mod lanes are probably the easiest to calculate when they will take effect, since each stage is only the length off the lane’s clock division. The tracks themselves have the most variety as far as pulse count and length.

If I cut all of the Position/Pulse modifying params, and all of the existing per-stage params, i’m not left with a lot of options… Since this modulation would just apply on the same steps, at the same time every rotation, a lot of what is left is kinda boring.

At a quick glance at the code, here’s what’s left after you filter anything that would effect the timing and anything that can just be configured on the stage. I also removed anything of the pitch related destinations since you can just set the pitch on a stage.

(pulled form the code)


Pulse Div (a fav of mine on Ctrl) is the one that I could see as a great per-stage setting. Potential UI issues aside, I think that would be the only one I’d add to the wish list.

This is all just off the cuff and maybe I’m missing a parameter, is there one in particular you are looking for per-stage?

What got me thinking about this originally was actually just a “boring” destination, lol. I was wanting to quickly modulate Octave in an upwards or downwards direction and to keep it consistent. With the current Pitch per-stage option you can only move the pitch upwards (unless I’m overlooking something?).

Also in addition to the ones you mentioned, the destinations: Accumulate, Accum Rev, Accum Invert, Accum Polarity, Accum Reset, Gate Length, Gate Scale, Mute, Pitch Offset, Pitch Post, Pitch Pre, Root, Scale (User), Trk Out Swap.

Some of these could be set per-stage (like the Accumulator destinations) but having the option to make quick changes via the Mod Lane really helps with the workflow and more on-the-fly decisions. Plus also having the option to quickly mute a Mod Lane with one of these mods would be a nice performance tool, or quick ideas tool all while keeping the mods in sync with Tracks.

I can get really cool modulations for these destinations going when I have the Track Lanes set to 1 pulse per stage, but then once I change the pulse count on a Track it’s a bummer I can’t keep it in sync with the new timing.

As far as the UI goes, can’t it all just stay the same, with the only change being an option in the Lane Setup menu (ALT + MOD) whether or not to sync a specific mod lane to Track 1 or 2? For example, if you select in the Lane 1 Setup menu to sync Mod Lane 1 to Track 1, once you go into the Mod Destinations for Mod Lane 1, then all the unavailable timing destinations are just greyed out - indicating that it is currently synced to a track. Also once you sync a Mod Lane to a track, it is only available to be assigned to the Track it is synced to (with the other options greyed out also to serve as an indicator it is synced).

First, the pitch stage value will override that stages pitch slider. it starts at 0 and goes 5 octaves, you can set the stage transpose to push the 0 into the negative voltages.

You can achieve what you were looking to do with the accumulator, set the mode to track if you want to transpose the whole track on each cycle or set the mode to stage so it only affects that one stage :slight_smile:

more in this thread:

The mod lanes do not work like the accumulator. They are CV sequencers (aka custom LFOs) and if they were in sync with the destination track, they do the same thing on the same stage, every cycle. In that case, you can just set the stage value to what you want, the effect is the same

For example, if you set a synced modulation to increase by 1 octave, it would apply that same 1 octave mod to that same stage, every cycle; it is the same as setting the pitch on that stage to 1 octave higher.

Now, accumulators on everything would be amazing :star_struck:.

It can be a little more cumbersome to make these changes via the menus however. I guess my main point with having it available through Mod Lanes is the speed and quick experimentation that could be achieved while keeping it in sync. I know you could achieve the same effect through the menus, but in practice using it as an interactive hands on module, the interaction is very very different having those destinations available synced up via Mod Lanes

Maybe I wasn’t clear about what I wrote about the accumulator. I know the Mod Lanes are nothing like an accumulator. What I meant was just having the option to very quickly throw in mods for Accumulator (and other) destinations.

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I agree with mtamayo about being able to sync the mod lanes to a track. I just came looking here to see if it was possible because I couldn’t figure out how to do it manually. I saw the Loopop video tutorial where he mentions you could manually but I haven’t understood how that is possible with this firmware? Setting what you want on stage value does give you option to keep consistency but having modlane sync to track opens up great performance possibilities with the ability to mute specific mod lanes because that would quickly change up the modulations in a more predictable manner.

Or even better yet . . . wouldn’t it be possible to give mod lanes to have their own pulse count on each stage? This way you could keep them independent and you could sync them up manually if you want. That would be AMAZING