IRDust (prototype convolver)

[tico-tico]

Somethin is wrong with latency compensation. The dry output's delay is 64 samples (not 128 as plug reports), not sure about wet.

[mystran]

Somethin is wrong with latency compensation. The dry output's delay is 64 samples (not 128 as plug reports), not sure about wet.

Oh, thank you for reporting this, this is a simple bug, will fix later today.

As for resampling: only necessary when IR rate is different from project rate, and only done when loading an IR (not realtime), but still adds latency sadly. As variable plugin latency is problematic in several hosts, I opted for the more compatible approach of simply using a fixed value everywhere.

edit: as for libsndfile, I'm aware of that library, but .. well it's LGPL so I'd have to package it as a separate DLL .. hmmh..

[tico-tico]

as for libsndfile, I'm aware of that library, but .. well it's LGPL so I'd have to package it as a separate DLL .. hmmh..

Yep, as a separated dll. But it'll help get rid of "please add xxx format" requests in one moment.
If it matters, Reverberate uses it too.

[mystran]

0.0.9 update, should fix the dry-path latency to be correct.

[anwaypasible]

greetings from the chicago area..

i'm experiencing a problem using your plugin.
i use liveprofessor as my vst host (with asio4all and virtual audio cable)

your plugin loads fine .. the plugin works fine ..
but when i try to close the plugin in liveprofessor .. liveprofessor freezes up.
when i try to close liveprofessor .. it freezes at 'unloading irdust' and i have to force liveprofessor closed with the task manager.

i told the developer of liveprofessor, he said he would download the plugin and try to recreate the error.
he also said it should be fairly easy for you to run the plugin in debug mode inside liveprofessor.

here's the link to liveprofessor:
http://audiostrom.com/?page_id=8


you deserve a token of thanks, because the only other 64bit convolution plugin on KVR is nadIR.
it's a plugin made specifically for guitar cabinets and amplifiers with an impulse length limit of less than 1 second.

my impulse responses are almost 2 seconds long.
using your plugin to convolve the inverted echo of my room, i was able to shave 4 decibels off the decay .. sharpening my impulse response and making the audio sound more pronounced.

i learned something..
i ran one sweep and recorded the impulse response, then loaded that in the convolution plugin.
my impulse response improved (the decay went down)
i ran the sweep again with the convolution applied and i found that i could record more of the echo and thus make it go away.
i'm using two instances of irdust, with two impulse responses recorded at the same microphone location.

the second layer of convolution isn't linear like the first layer.
i think that is the limit of the bitdepth.
right now i'm only recording in 16bit mode because my creative x-fi elite pro died and my onboard soundcard only records at 16bit.
maybe 24bit is the same.

i can clearly see the reduction in the impulse response, as well as the waterfall.
the second layer of convolution takes off a lot of the decay in the treble frequencies and upper midrange.
not so much in the lower midrange and bass.
but my speakers from the early 1990's love it.

another thing i noticed using your plugin..
the width control doesn't seem to do anything.
i don't hear any difference at 0% or 100%
i'm using the plugin with the mono-in option.


thanks for your time!

[mystran]

greetings from the chicago area..

i'm experiencing a problem using your plugin.
i use liveprofessor as my vst host (with asio4all and virtual audio cable)

your plugin loads fine .. the plugin works fine ..
but when i try to close the plugin in liveprofessor .. liveprofessor freezes up.
when i try to close liveprofessor .. it freezes at 'unloading irdust' and i have to force liveprofessor closed with the task manager.

i told the developer of liveprofessor, he said he would download the plugin and try to recreate the error.
he also said it should be fairly easy for you to run the plugin in debug mode inside liveprofessor.

here's the link to liveprofessor:
http://audiostrom.com/?page_id=8

Sure, I'll take a look and see what's going on.

another thing i noticed using your plugin..
the width control doesn't seem to do anything.
i don't hear any difference at 0% or 100%
i'm using the plugin with the mono-in option.

The pre-width control will adjust the side-channel of the convolution input (has no effect on the dry signal, which is simply the original input signal as-is). The pre-width is grayed out (and has no effect) in mono-in mode, as mono-in is essentially the same as dual-mono with 0% pre-width, while normal "independent channels" dual-mono would be at 100% width (this is when you want to process each channel separately, by the different channels of the IR). It's purpose is to allow one to narrow the "source" of convolution reverbs.

The post-width control will do the same for the convolution output (only the wet signal, again): 0% gives mono signal out, 100% gives regular stereo output. It's intended mainly for reverbs, to allow narrowing the actual reverb sound itself. If the impulse response is mono and the pre-width is 0% or mono-in, then the result on both channels will be the same anyway (just mono-convolution), so post-width won't do anything as there is no stereo side-channel to reduce.

For use as non-reverb convolution (eg filter IR or similar) with independent stereo input channels, you'd normally want to turn dry signal completely off, set both width controls to 100% and then set it to dual-mono. Then if you have a mono IR, you get the same processing for each channel [and at some future point of time the mono-IR + dual-mono operation will hopefully be as fast as mono-in] and if the IR is stereo, then each of the input channels is processed with the corresponding IR channel.

[mystran]

greetings from the chicago area..

i'm experiencing a problem using your plugin.
i use liveprofessor as my vst host (with asio4all and virtual audio cable)

your plugin loads fine .. the plugin works fine ..
but when i try to close the plugin in liveprofessor .. liveprofessor freezes up.
when i try to close liveprofessor .. it freezes at 'unloading irdust' and i have to force liveprofessor closed with the task manager.

i told the developer of liveprofessor, he said he would download the plugin and try to recreate the error.
he also said it should be fairly easy for you to run the plugin in debug mode inside liveprofessor.

here's the link to liveprofessor:
http://audiostrom.com/?page_id=8

Sure, I'll take a look and see what's going on.

Ok, so LiveProfessor appears to close the editor window and only afterwards calls the plugin to close it's window. Apparently this was causing a crash/dead-lock as the plugin still thinks the editor is open and attempts to close it. I added the relevant code to detect this situation (it was apparently partially done, but not finished for some reason) and it appears to be working fine now.

I suspect that it might make sense for LiveProfessor to fix this as well, as there might be other plugins where it might cause trouble, since as far as I know, none of the mainstream hosts do this. But it's fixed in IRDust now, and my other plugins will receive updates in the near future.

Uploaded 0.1.0 that should fix this issue [edit: also updated the screenshot now]

[anwaypasible]

just wanted to say it works here too.

[camsr]

What's a reliable way to normalize an impulse response file?

[mystran]

What's a reliable way to normalize an impulse response file?

Good question. My current normalization is to simply take FFT of the whole thing, then scan through for the highest amplitude and scale that to a known level.

It appears to work quite acceptably with most reverb-type impulses, but long impulses with fairly flat envelopes get normalized somewhat low, as the theoretical running response could be quite a bit higher than the response to practical musical signal. One possible alternative would be to go through the impulse using a fixed-size moving window instead, since in practice if there's a significant decay envelope (like in a natural reverb) the initial part will dominate.

[Prestidigitator]

Works good, unless i need to reopen saved file. VST loader stops on this plugin when loading, after that freezes entire program.
I've tried without impulse response too. It reloads with no troubles, but it doesnt do any magick then

IRDust was my first attempt to convolution plugins, but i've tried Freeverb3 and NadIR after that and they work without problems here.

[mystran]

Works good, unless i need to reopen saved file. VST loader stops on this plugin when loading, after that freezes entire program.
I've tried without impulse response too. It reloads with no troubles, but it doesnt do any magick then

Which hosts are you using?

[Prestidigitator]

I am using Jeskola Buzz mainly.

[mystran]

I am using Jeskola Buzz mainly.

Hey, sorry for slow reply, it might be Buzz related as I can't reproduce it in other hosts, but I'll put this on the list of known issues and take a closer look at it as soon as I can find a moment.

[camsr]

NM, something weird with DLing that file on Firefox