Surge XT 2.1 testing and feedback thread


Yeah we have simd implementations of a bunch of sin approximations in surge also - and I already limit pan to recalc every 8 samples and smooth (no need for pan fm I don’t think) but I don’t do obvious things like unmodulated pan skips the recompute and stuff since unmodulated pan is a very common case

The other trick is I want to revisit the egxvca for the sort of entire parallel structure while still having sample accurate attacks. But since the envelopes are also at a control rate that means the envelopes aren’t in block phase but this is all a detail none of you care about so I should just leave shorthand ideas in my notes :slight_smile:

Luckily thanks to the work qno did I have full access to all my arm profiling tools in clion so should be a good investment of a day to get that alpha tag gone.

yeah, was going to mention no need to compute pan every sample, but I know you know this stuff. You don’t do envelope at full rate? I never really tested it, but I do envelope at full rate. I stole the VCV adsr - it’s SIMD (hoizontally), and quite efficient.

I do envelope at full rate but I calculate the envelope as block size 8 piecewise linear segments

I’m considering if this matters for super short attacks and decays but I don’t think it does

But I’m still considering it which is why this module still has an alpha tag :slight_smile:

You are correct that the savings from the pw lin approx may be well replaced by not doing that and doing simd envelopes at least for the digital case

This is all the “next week in egxvca” work i need to do as we get ready for 2.1 in jan or so


Oh sigh. I changed the loading path to be smaller and ‘only load fx presets not wavetables’ in the fx. And that change of course worked for me. Because the way I coded it fell back on my surge vst install.

So the nightly right now has fx presets broken if and only if you don’t have the VST.

I have a fix I can push this morning and will, and will re-open the minimal load issue to try again. Should be a nightly before noon NYC time.

But also: you should install the surge VST. It’s a bucket of fun :slight_smile:

Edit: the nightly with this fix is now available

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Yeah! It works again! :slight_smile:

Thanks for the fast fix (and the explanation).

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Fantastic work!! All my Surge XT infused patches have a fat fun sound! I noticed something quirky that seemed like a bug issue. I like the FM3 osc and have started experimenting with it in earnest, and when I have used the right click on the 3rd operator pitch and tried to insert C3 or C5 for the pitch , the rack crashes every time. Maybe that is not preferred for pitch info for Surge modules, so maybe not an issue.

Oh can you let me know which version you are running? I know what it is but I thought we had fixed it


Ok, I grabbed a nightly over a week ago, when I first saw quad AD available with no graphics yet, I was waiting for a new official update thru rack updates, but I could grab a new nightly, just worried about a gig this week and didn’t want to update anything this week. I’ll check out a new build, thanks.

Yeah probably a few weeks until 21 is in the library but I think we fixed all that string handling

If not lemme now and I will look more deeply of course!


Those modulation value options are just incredible!

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Is there yet apreset change in surge vst

you mean does the surge vst support midi program change or something? nope. but that’s a bit off topic for this thread which is about the next surge rack release.

Found a minor visual bug in Mod Matrix. Just pulled the latest Mac x64 nightly.

If you set the modulation depth to negative, the indicator jumps outside of its bounding box and into its left neighbor. In the image below, you can see that the negative modulation on knob 2 is jumping into the indicator for knob 1.

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Ha thanks it was a one character fix - really appreciate the report! new nightly building now.


OK folks I’ve closed all the open issues we have in our 2.1 milestone; these four new modules and numerous bug fixes also. The next nightly will be up in about 5 minutes.

Barring feedback here or in our discord or GitHub, sometime next week I’ll submit this to the library as 2.1, so that means if you are in the mood for some careful weekend testing, it would be welcome!

here’s the changelog for all the bugs we fixed for 2.1, except for the matrix one above

and if you have ideas for new features of future versions, feel free to share them here too, but please flag them as such so we don’t confuse them with bugs. We already have a couple of new module and other ideas for a 2.2 release, but will probably turn back to the VST and a sampler for a wee bit once we get this pushed out.



This goes really fast.

First “bug”: Changelog has a wrap around in the year. :slight_smile:

See: " 2.1 - In Beta Now (As of Jan 11, 2022 / 4d2133d)"

Thanks for the effort and the extremely nice modules!

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Great stuff, but I’m having minor issues with the Wavetable VCO:

I actually read the changelog, which states that the 3rd-party wavetables will be gone and one should press “Download extra wavetable content” in the context menu. So I checked and the 3rd-party WTs were still there. I pressed “rescan” and they were still there. I tought “who knows what I’m missing out with extra content” and pressed “download” anyway. Now I have everything twice in the context menu.

Press “rescan” again, no change. Restart Rack, still no change. Press “Reveal user WT directory”, which takes me to C:\Users\abc\Documents\Surge XT\Wavetables, which is not the 3rd-party WT directory.

So I navigate to the Rack user folder and it turns out that there are now two folders with 3rd-party WTs: C:\Users\abc\Documents\Rack2\plugins\SurgeXTRack\build\surge-data\wavetables_3rdparty and C:\Users\abc\Documents\Rack2\SurgeXTRack\SurgeXTRack_ExtraContent\wavetables_3rdparty. The latter has the recent update date, but the former has the built-in WTs and other stuff and has the old date only for the 3rd-party WTs.

So plugin upgrades don’t delete prior directories so if you had there’s no need to download extra. the extra will have shipped with the old version.

if you blow away your surge xt plugins directory and restart and redownload you will get only the factory and will have to extraify

That means C:\Users\abc\Documents\Rack2\SurgeXTRack\SurgeXTRack_ExtraContent\wavetables_3rdparty is the correct new folder which will receive future updates and I should delete C:\Users\abc\Documents\Rack2\plugins\SurgeXTRack\build\surge-data\wavetables_3rdparty. Is that correct?


or just delete Rack2\plugins\SurgeXTRack altogether and re-download which will have same effect