VST plugin issues with R2022-11-25

[Gwennie]

Very happy to see that VST support has arrived (back) in the latest dBpoweramp release!

Unfortunately a couple of VST3 effects I've tried seem to produce silence.

Spoon: If I may suggest, try putting your VST host through its paces with Stereo Tool - it packs in a huge amount of processing for a single VST effect, and its complexity seems to expose problems in VST hosts readily. It also produces a comparatively huge amount of state data to serialise.

Currently, when used with dBpoweramp, the VST3 version of Stereo Tool seems to produce silence, and the VST2 version seems to introduce regular-spaced artefacts in the left channel (buffer issue?); so it would seem well-placed to help narrow down any remaining host bugs.

[PeterP]

Re: VST plugin issues with R2022-11-25

Thanks for the bug report.

Any other VSTs than Stereo Tool that cause trouble?

Stereo Tool VST3 seems to crash in IAudioProcessor::process(), so far we couldn't get it working at all.
Stereo Tool VST2 works for me, output appeared OK. Any specific content that you tried it on? File format / sample rate / bit depth?

[Lynx_TWO]

Re: VST plugin issues with R2022-11-25

+1 on using StereoTool as the test VST3. It's a monster.

https://www.stereotool.com/

[Gwennie]

Re: VST plugin issues with R2022-11-25

Thanks for looking into this!

Any other VSTs than Stereo Tool that cause trouble?

I've had a look for some free VST3 effects that don't work and you can use for testing without too much trouble, and so far I've found that the majority produce silence, unfortunately. I've not looked into what the ones that fail have in common. Maybe just whether they support 32-bit or 64-bit precision samples?

Here's some: ToneLib TubeWarmth, Red Rock Sound EQ302, Analog Obsession ReLife, SNFK Music Unifilter, ChromaDSP HarmonicReverb.

Stereo Tool VST2 works for me, output appeared OK. Any specific content that you tried it on? File format / sample rate / bit depth?

Everything I've tried is WAV / 16-bit / 44100Hz.

With Stereo Tool VST2, I just applied it on a WAV file containing a sine wave at -40dB (downloadable here).

This is what the output looks like when processed with Sound Forge:


This is the output with dBpoweramp (same settings) - notice artefacts in audio and extra silence added to beginning:


Zoomed-in view of the regular artefacts:


If there's anything you'd like me to test, do let me know.

[PeterP]

Re: VST plugin issues with R2022-11-25

Thanks for all the details, compatibility issues are being investigated for the next update.

Looks like many VSTs don't work at all if the host application doesn't access their user interface first, on the exact VST instance doing processing. Which is very problematic for converter type apps that save presets and use it for automated jobs. It doesn't matter if you touch VST settings panels from dBpoweramp first; a new separate instance is created for processing always.

I'm trying to come up with some mitigation technique for this.

It's even worse than it sounds, cannot stick and reuse VST instance that was configured before, since dBpoweramp runs multiple conversion threads and needs multiple effect instances working.

I hope some VST developers read this and can fix the problem on their end, which has to be easier than fixing it on our side.

[Gwennie]

Re: VST plugin issues with R2022-11-25

Thanks for continuing to look into this... It sounds like a nightmare.

Nobody like a backseat coder, and I understand you're creating your own independent implementation, but it might be worth having a quick look at the open source and now abandoned MrsWatson. It has no GUI and supports VST2 only, but doesn't have any issues with any plugins I've found so long as you supply a .fxp file created in another host.

[hvz]

Re: VST plugin issues with R2022-11-25

Hi, I'm the owner of Thimeo, the company behind Stereo Tool. One of our customers just pointed me to this thread. Let me first agree: VST development is a nightmare, probably from both sides.

I wanted to try out why Stereo Tool crashes in dBpoweramp, but so far I've been unable to make it see the VST in the first place. I went to Music Converter, and added a "VST Plugin" under DSP Effects. But when I click on "Folders..." nothing happens, and all the other settings in the popup are disabled. What am I missing?

Silence for many plugins: We have seen hosts that reset all the settings to 0 if you load a new plugin, or do that with newly added settings if you load a newer version of the same plugin. That's a VERY bad idea, since setting everything to some value can easily cause invalid combinations of settings. Obviously nothing should crash if that happens, but we have seen that it did do that in Stereo Tool. We have added fixes to prevent this from happening in the recent beta builds, not yet in ther released version. Even if it prevents crashes, the audio will be very bad - if just one of those new values indicates a volume, setting it to 0 would indeed cause silence as output, as someone mentioned above. So far I've only seen this happen in VST2's.

[Spoon]

Re: VST plugin issues with R2022-11-25

Send us an email and we will set you up with a registered version.

https://www.dbpoweramp.com/email.htm

[PeterP]

Re: VST plugin issues with R2022-11-25

Notes from the person responsible for the new VST adapter.

As far as I can tell Stereo Tool now works.

I basically threw out all my VST v3 frontend code and repurposed "vst2wrapper" module from VST SDK.

This seems to have addressed all unique per-VST bugs. I can only recommend anybody writing VST v3 frontend to do exactly the same. Before I spent weeks trying to "fix" this without any progress whatsoever.

[PeterP]

Re: VST plugin issues with R2022-11-25

It might be easier for you to try foobar2000 VST adapter, which is based on the same code as dbpoweramp's one, but freely available with a backlog of archived old versions:

https://www.foobar2000.org/components/view/foo_dsp_vst3

Last version that had trouble with Stereo Tool:

https://www.foobar2000.org/components/view/foo_dsp_vst3/release/0.10.1

(vst2wrapper was added in 0.11)

[hvz]

Re: VST plugin issues with R2022-11-25

Ah, good, that explains why it's working on my end
Thanks for the update!