[VeJa Titan] Aliasing problem

I think Titan amp is affected by aliasing problem. You can hear it clearly between 0:09 and 0:20
Can it be mitigated somehow?

https://voca.ro/1bEgWSwyAXo8

This is what I’ve used for clip recording.

:nauseated_face:
I didn’t noticed that, I don’t like the sound of Titan Amp, there too high frequencies. But I will ear if I have the same issue.

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I tried the AmpVST with a distortion in front since it is not a so high gain amp and oversampling 8x helps, aliasing still there but less noticeable than Titan and Onyx. Maybe we can just stick an oversampling and downsampling plugin in front of plugins that generate lot of harmonics? These operations obviously increases CPU usage. This is a key factor to consider in buying a digital amp modeler.

Are you using always the same cabinet?

Yes, it’s not related to cabinet, aliasing is there even with no cabinet in the pedalboard. Maybe it can be solved with an high cut filter for > 20kHz frequencies.

hmm ok. I asked because we discovered (and fixed) that issue on the cabinets. I’m not sure if the fixes are already available.

No they are not, but testing on this is very much appreciated! for now, you can get the WIP updated versions here :slight_smile:

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This is Titan only (no cab) Vocaroo | Online voice recorder

This is Titan + faIR Vocaroo | Online voice recorder

I still hear aliasing with updated faIR.

I replaced this folder MDW/fair-cabsim.lv2 into /root/.lv2 and rebooted the Dwarf. Is it correct?

yes, that will work.
Alternatively using tar cz fair-cabsim.lv2 | base64 | curl -F 'package=@-' http://192.168.51.1/sdk/install you dont even need the reboot

I’m able to replicate the issue, and even managed to solve parts of it already. I’ll bring this up with the rest of the team so we can see how best to proceed.

Thanks for the report!

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Thanks a lot Jan! If you need beta testing feel free to ping me :grin:

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Could the solution be applied system wide? I found same problem on cream machine too and maybe other plugins are potentially affected.

Seems that even Neural DSP is affected :sweat_smile:

Great explanation! So it seems that 8x oversampling is the best tradeoff for live playing. 16x I suppose would introduce too much latency.

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Yes, oversampling kills performance.

Same deal with ChowTapedelay. It may be good to patch the ttl to not allow full range of antialiasing settings?

This is something that would be nice, yes, but sadly, I don’t think it’s safely possible.

Looking at the Titan for instance, as it was made specifically for MOD, things tend to get designed with a sample rate of 48Khz in mind. Simply oversampling the full plugin is not only wasteful in terms of CPU, but can also result in unstable filters.

Imo this is something for the plugin developer to keep in mind, and make the tradeoff when it comes to the CPU load and (partially)oversampling.
Talking with the rest of the team, the Titan will probably get a toggle to enable/disable oversampling for the tube emulation part of the plugin.

For the Onyx things are a bit more tricky as the internals are completely different, and from my tests, I can not reduce the artifacts without changing the characteristics of the amp. Since this plugin is a bit older, we need to be careful changing things as we don’t want to break people’s pedalboards :sweat_smile: .

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I’m wondering how would the Onyx sound with oversampling enabled. Maybe you can let the user choose whether turn it on or leave it turned off.

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well, the Onyx is one of those plugins which starts to behave quite differently when the sample rate changes and even becomes unstable at some knob combinations.

I did however ask the original author Jarno to see what’s going on there, so perhaps he can get things sorted :slight_smile: .

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