Using Thor to Create Smooth and Interesting Convolution IRs

[selig]

Here we go folks, the RV7000 MkII is the first major update of an existing device since Dr Octa Rex. To help get you started, here's a simple idea I've been having fun with to quickly and easily generate many useful reverb effects that can be expanded on in an almost infinite number of ways. 

First the basic concept:
By using noise as an IR source we can create smooth "perfect" reverb effects because white noise represents all frequencies evenly. 

We will use white noise from Thor to first create unbelievably smooth and "pure" reverbs that work well at any size setting. The Decay Time on Thor's Amp Envelope will control the max length of the reverb (see the pic of Thor below for details). The max IR length allowed in the RV7000 MKII is around 12 seconds, so you won't want to use a decay time any longer than that (and often much shorter, except for special effects). 

The resultant reverb is very pure or even "generic" sounding, with no pitch modulation or similar effect going on. If you want that effect (or something close to it at least), simply add another RV7000 before this one and set it to Hall - adjust Mod Amount to taste, and use wet/dry if needed to reduce the effect - try starting @ 50%.

More Details:
Here's a shot of the setup for creating your own IRs from Thor. By using the Parallel Outs to feed the Sampling Input, you can reduce the fader level on Thor without changing the sample level, as this sound isn't one of those sounds you need or will want to hear loud very often! Bring the fader down to -20 dB or so for starters, just enough to hear the basic effect to be sure it's as you wish.
        


Here's the included Thor preset, "StereoNoise3sec" showing the key aspects of the patch:

    


With this setup, all you need to do is hit the Sample Button on the RV7000 in Convolution mode, and play a note on Thor. Watch the meters to know when the decay is completely finished, then hit the EDIT button in the sampler window, then "Crop" and "Normalize" and name the sample and you're done!

Create a drum beat to audition your new reverb, something simple so you can hear the decay. Adjust the RV7k's Decay control to shorten the apparent room size, and use HF Damp to create a more realistic and natural "room" effect.

That sounds pretty good, right? But there are still so many variations you can create, and it's so simple you can do custom IRs for each song if you like!

Included Example Files:
1-Basic 3 second decay, default setting for the included Thor Patch.
2-Use a slower attack to create a "soft" delay before the main reverbs hits (different than pre-delay).
3-On Thor, raise the sustain to FULL, and sample a note that is held for a 1/4 note or so. This will create the now classic 80s AMS Reverb preset NonLin2, aka the classic gated sound.
4-Reverse the sample in the editor for cool reverse reverb effects - adjust negative pre-delay to start the effect sooner.
5-Use Filter 3 in Thor as a High Pass to create less boomy or muddy reverbs.
6-Use Filter 3 in Thor to create filter sweeps, especially with higher resonance settings - enjoy trippy reverbs!
7-Use LFOs on the VCA and/or Filter 3 to create rhythmic and flutter effects.

Important Note:
Make SURE decay is set to MAX and HF Damp is OFF to hear these IRs in their original state, which is especially important for the reverse and NonLin examples (and possible the slow attack example). Explore further: create exponential decay curves, use the Multi Osc (with high Detune settings) to create interesting and less "smooth" reverbs, add the mono osc 3 (with or without the stereo oscillators 1&2), try different filter types, explore high resonance filter sweeps, try tempo synced LFO or Step Sequencer effects on Filter Frequency or amplitude, set the Amp Decay to 12 seconds to create super long reverbs (set Size to higher values to extend the decay time), explore the HF damp and Decay's effect on your IRs… go nuts!

Here are the example IRs, zipped into a single file for convenience:
https://dl.dropboxusercontent.com/u/147 ... 20Thor.zip

Here is the Thor patch used to create these examples:
https://dl.dropboxusercontent.com/u/147 ... c.thor.zip

And finally, here is the Reason 8.3 song file used to create these examples, already hooked up to get you started:
https://dl.dropboxusercontent.com/u/147 ... reason.zip

Enjoy, and share the results of your explorations here if you like!

[Benedict]

Thanks Selig

[Ostermilk]

This is a great little workbench setup for creating different diffuse fields for synthesized IR's.

Remembering that most reverberant spaces and reverb devices usually consist of reasonably clear echoes (early reflections) at the beginning which then 'devolve' being ever increasingly multiplied and modulated by the eq characteristics of the room as the sounds disperses from it's original source. Using this knowledge of how we get auditory cues from our surroundings it isn't difficult to imagine some convincing real and unreal synthesized spaces. This setup is great for making those tails especially with some creative filtering over time to emulate how a natural (or unatural) space would cause the sound to decay.

Don't forget either than you can make an EQ filter out of anything you like the sound of, for use in RV7000's convolution engine too. All you need to do for that is to load up a sound into an audio editor and with a few iterations you can time shrink it without changing it's pitch so it's only a few ms long and you'll have a basic filter that will have something of the tonal characteristics of the original sound sample.

Using such filters you can then even apply them to some early reflections coming from the venerable old RV7 (an excellent ER generator IMO). with your own diffuse feild generated here and record the result for your own tonally mutatated IR's.

[selig]

This is a great little workbench setup for creating different diffuse fields for synthesized IR's.

Remembering that most reverberant spaces and reverb devices usually consist of reasonably clear echoes (early reflections) at the beginning which then 'devolve' being ever increasingly multiplied and modulated by the eq characteristics of the room as the sounds disperses from it's original source. Using this knowledge of how we get auditory cues from our surroundings it isn't difficult to imagine some convincing real and unreal synthesized spaces. This setup is great for making those tails especially with some creative filtering over time to emulate how a natural (or unatural) space would cause the sound to decay.

Don't forget either than you can make an EQ filter out of anything you like the sound of, for use in RV7000's convolution engine too. All you need to do for that is to load up a sound into an audio editor and with a few iterations you can time shrink it without changing it's pitch so it's only a few ms long and you'll have a basic filter that will have something of the tonal characteristics of the original sound sample.

Using such filters you can then even apply them to some early reflections coming from the venerable old RV7 (an excellent ER generator IMO). with your own diffuse feild generated here and record the result for your own tonally mutatated IR's.

The built in HF Damp control works well to simulate air absorption of natural spaces.

You can get some very interesting FX by using high resonance filter sweeps on the noise, and I've also used the Mult-Osc with high detune settings to create more interesting (and less diffuse) sounds. Simply substitute the Multi-Osc for each Noise Osc for stereo IRs.

Also, check out my #Reverb submission, which uses bird and cricket field recordings for all the long reverb FX!
https://www.propellerheads.se/s/H055ZVtU

[LarsK]

And finally, here is the Reason 8.3 song file used to create these examples, already hooked up to get you started:
https://dl.dropboxusercontent.com/u/147 ... reason.zip

Is this file still to be found somewhere?

[selig]

And finally, here is the Reason 8.3 song file used to create these examples, already hooked up to get you started:
https://dl.dropboxusercontent.com/u/147 ... reason.zip

Is this file still to be found somewhere?

Crap, something happened to that dropbox account. I’ll see if I can dig up the original file and repost.
Basically it’s just two Thor (or two) feeding the sample inputs of Reason, which in turn feed the sample inputs of all sampling instruments including the RV7000. Using noise, filtered or not, creates these beautiful diffuse and smooth reverb tails which are more difficult to generate with algorithmic reverbs IMO.