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TX16Wx and polyphony

cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 1:23 am TX16Wx and polyphony

Am I the only one who has run across [what I suspect is] polyphony issues with TX16Wx, particularly with larger and more complex performances? Sometimes I get a lot of dropped notes, especially if there's programs with RR's playing but it seems to happen with other programs as well, almost randomly. This makes it kind of hard to reproduce so I don't have any concrete examples of what I'm talking about right now. Weird thing is, it appears that this issue creeps in after a while, when a project has been running for some time. Upon first load it usually works as expected. Then, after having started and stopped playback a few times, notes start disappearing at random. Even during passages where there's very few instruments playing! It's almost as if the polyphony isn't reset properly when things stop playing and some programs sort of keep hogging voices.

Obviously I can't rule out some kind of user error here, in fact I don't even know if polyphony is the culprit. At any rate it's a very frustrating problem which makes using TX on larger project a complete crap shoot, unless you keep reloading the project every 15 minutes or so. So any thoughts or suggestions on this matter would be very welcome.

TIA
elcallio
KVRian
 
1265 posts since 27 May, 2005, from Stockholm

Postby elcallio; Sat Jun 17, 2017 1:59 am Re: TX16Wx and polyphony

If you can set up a project (reaper preferably, easier to debug) and give instructions on how to make the issue appear, I'd be happy to look at it.

But notes dropping sounds weird. In general, TX16Wx will always prioritize new notes over old, with oldest being killed first, so even if a voice is "stuck", it should be the first to go.
Try sending MIDI All sounds off on all channels to the plugin. This will brute kill all playing voices. No chance of anything being stuck after that.
You can also experiment with the per-slot polyphony settings to make sure one channel does not take to many voices.
TX16Wx Software Sampler:
http://www.tx16wx.com/
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 2:29 am Re: TX16Wx and polyphony

I'll se what I can do about providing you with an example project. I do have a REAPER project here using various freeware samples that displays this issue, but it might be a hefty download as I assume that you're going to need all the samples and not just the project file.
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 2:58 am Re: TX16Wx and polyphony

You got PM :)
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 7:39 am Re: TX16Wx and polyphony

I can't really confirm this without sorting through a number of projects that I've used TX in, but I just realized that the only instruments that appear to crap out in the way described above are instruments with RR's. So this might not be a polyphony issue after all. At least in the project I sent you, it's the RR ones that tend to drop notes. I don't know if that helps pinpoint the issue (if you are even able to reproduce it), but I just wanted to mention it.
elcallio
KVRian
 
1265 posts since 27 May, 2005, from Stockholm

Postby elcallio; Sat Jun 17, 2017 9:07 am Re: TX16Wx and polyphony

Thanks for the project (pretty nice). However, I've had it on repeat for ~30 minutes, and I have not had a single dropped or misplayed note (afaich). And inspecting the instance definitely confirms no stuck notes or anything. If RR is a problem, I have not managed to spot it...

Your sound set is pretty big though. ~900MB on disk, and unfortunately about 2x that in memory, making the DAW process working set about 1.9GB. And that is without the FX (the plugins which I don't have). I don't know your system setup, but even if you have enough RAM, you might see cache misses galore which in turn could screw with the DAWs timing. Reverbs (which I think are aplenty in the project) are also memory hungry. Does the project play better without FX?

Not sure where to go from there.
TX16Wx Software Sampler:
http://www.tx16wx.com/
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 11:06 am Re: TX16Wx and polyphony

Hmm. So are you saying there might being some kind of RAM/CPU bottleneck thing happening here?

My machine is borderline ancient (AMD Athlon II X4 630 / 16GB DDR3 RAM) but it normally gets the job done for pretty much everything I throw at it, at least with other plugins and within reason (i.e. as long as I don't have super duper oversampling things going on with live playback). Am I to take it TX16Wx might be sensitive to such things? If so that's the first time I've heard of it. REAPER's realtime CPU meter hovers around 35% for this particular project so on the surface it doesn't appear that anything is being maxed out. I would expect actual audio dropouts if my CPU/RAM can't keep up with what's asked of it rather than plugins randomly doing weird things. But then again I know nothing about the inner workings of TX16Wx and how it differs from other software samplers.

As for my "sound set being pretty big"... I guess I kinda had that remark coming, given your attitude towards sampling and samples ;) And to a certain extent I agree with you. But ~2GB is NOT big in this day and age. If that factors into it and there is something in TX16Wx that might prevent it from being used for anything beyond 1990's sampling it should explicitly say so on the first page of the website. IMHO.

Anyway, thanks for taking the time to check out the project. I'll try bypassing the reverbs (which are CPU reliant rather than "memory hungry") and see if it helps.
elcallio
KVRian
 
1265 posts since 27 May, 2005, from Stockholm

Postby elcallio; Sat Jun 17, 2017 11:42 am Re: TX16Wx and polyphony

TX16Wx is not more sensitive to CPU aspects than anything else, so don't take what I say as there being any special case. And I agree that 2GB per sé is not huge for a sample library, though having it in memory will tax the CPU cache somewhat (i.e. some memory might be slow-ish to access).

However, these are just observations in general, and if they had anything to do with your problem the most likely result would indeed be dropouts in processing (i.e. cpu overload), not dropped notes. I am frankly grasping at straws as to why you would ever get note drops. 35% cpu load sounds very reasonable for an older Athlon, in fact I am happy to hear! I miss my old AMD. :-)

And reverbs might hog CPU as well, but they are in fact often more memory hogs (and thus CPU cache killers) than pure processing monsters. Lots of buffers to do reflections.

But: I think I manages to reproduce some sort of RR issue with the sounds by actually soloing the Viola track. Let me check it some more...
TX16Wx Software Sampler:
http://www.tx16wx.com/
elcallio
KVRian
 
1265 posts since 27 May, 2005, from Stockholm

Postby elcallio; Sat Jun 17, 2017 12:08 pm Re: TX16Wx and polyphony

I found your problem. You have a modulation to AEG amp somewhere in your setup. This value is not cleared properly when the voice is reset/reused. So a voice might play with bogus values in this field, and end up with zero (or other weird) AEG values. How lame.
TX16Wx Software Sampler:
http://www.tx16wx.com/
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 12:23 pm Re: TX16Wx and polyphony

Right, sorry about sounding a little snarky, but your personal attitude towards sampling and sample libraries tends to come up more often than not in relation to TX16Wx so I guess I was jumping to conclusions there. I definitely belong in your camp when it comes to having a dislike for the insane sizes of modern libs but at the same time, 2GB is extremely modest (it wasn't a big deal even a decade ago) so your bringing it up ticked me off, I suppose.

The thing I've always loved about TX is that it's an actual SAMPLER rather than a black box front end for playing back libraries. It's all WYSIWYG and I can load up pretty much whatever I fancy and tweak it to my heart's content. That's one big reason I'm sticking to the orchestral libs of old right there; I'm in control. I will happily give up all true legato and 16 RR samples in the world for that.

But, yeah. Thanks for taking the time to investigate. I have no idea what might be the problem either, I guess I might have to load this project on my lappy and see if the problem persists.
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 12:25 pm Re: TX16Wx and polyphony

elcallio wrote:I found your problem. You have a modulation to AEG amp somewhere in your setup. This value is not cleared properly when the voice is reset/reused. So a voice might play with bogus values in this field, and end up with zero (or other weird) AEG values. How lame.


Ah-hah! That must be the AEG amp to mod wheel (or CC#11) thing that I've used a lot!
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sat Jun 17, 2017 1:16 pm Re: TX16Wx and polyphony

I suppose this is why CC#11 mapped to AEG Amp has misbehaved as well in the past? I remember having some funky issues with modulating AEG Amp when doing The Horus Heresy soundtrack, like completely unrelated midi channels suddenly and undesirably responding to CC#11. Again, it was very random and I didn't report it as I thought it was due to user error. I really need to get better at reporting bugs.
elcallio
KVRian
 
1265 posts since 27 May, 2005, from Stockholm

Postby elcallio; Sun Jun 18, 2017 5:10 am Re: TX16Wx and polyphony

2.4.2f update should fix the problem.
TX16Wx Software Sampler:
http://www.tx16wx.com/
cerendir
KVRist
 
67 posts since 9 Jul, 2006, from Sweden

Postby cerendir; Sun Jun 18, 2017 5:48 am Re: TX16Wx and polyphony

Yay, thanks!

Moderator: elcallio

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