Saturday, October 15, 2011

Reason 6 Thor Voice Bug

Update: I have developed a workaround, details are here.

This article is intended to explain the Thor Voice bug that has been observed by several Reason users in versions 4 through to 6. I first mentioned it here when discussing the Thor Shaper in Reason 4.

The bug concerns the way Thor handles creation of voices when it receives a trigger from the Step Sequencer. Normally, the Step Sequencer can generate triggers which open new Voice channels, allowing these channels to be used for effects (such as the LP Ladder filter, and the Shaper). By setting the Step Sequencer to trigger automatically via a trigger generated from the same Thor instance, it is possible to create a continuous Voice that stays open and provides an effects channel.

The bug is that hitting the Stop transport control, or selecting Export Loop/Song As Audio closes this Voice and the Step Sequencer fails to retrigger the Voice, and the channel is closed.

Earlier versions had a workaround, thanks to selig, that would help to solve the Stop issue, but not the Export Audio issue. Unfortunately with Reason 6 this workaround does not appear to work.

I present here a Reason 6 song file that clearly demonstrates the Stop issue. It consists of a Thor, a Subtractor synth that generates a continuous sequence of tones, and a second Thor that triggers the Subtractor. I did not use the Sequencer track to generate notes because I specifically want to show the behaviour when the sequencer is not running. Or to put it another way, the bug is a problem when you are working with the sequencer stopped, which is not uncommon when constructing patches.

When you open the example file, after an initial weird noise, you will hear the pulsing tone from the Subtractor, which is going into the Thor [Audio In 1], through [Filter 1], out [Audio Out 1] and into the Mixer. The Thor has a simple Step Sequencer (of one step) configured to generate a trigger and create the Thor Voice so that Filter 1 actually 'exists'. The Step Sequencer is triggered periodically by LFO2, and you will see that the Run button is automatically enabled & highlighted.

Now press Stop on the Transport panel - the sound will stop. Note that the Run button is still highlighted - this is because the LFO2 is frequently triggering it. But the Voice is not created and no sound will be heard. This is the bug. What should happen is that the retriggering of the Step Sequencer by LFO2 just after Stop is clicked should re-open the Voice and we'd hear the sound, but it does not and remains silent.

Manual intervention is required to restore the Voice - now click the Run button once, it will briefly go off and then be retriggered by the LFO2, and the sound will return.

Pressing Play will also 'fix' the problem, but again this is primarily an issue when working with the Sequencer stopped.

A similar issue, but not demonstrated by this example (I'll need to create a slightly different version) occurs after Exporting As Audio.

As anyone who follows this blog will know, I work a lot with CV within Reason. I like to create all sorts of interesting CV devices, and Reason provides almost an unlimited capacity to experiment with these things. In this regard it is almost bug-free, but this one particular bug is a real problem for my designs and I've yet to find a suitable workaround in Reason 6.

It also significantly reduces the usefulness of the Thor Shaper as a viable audio effect.

Thor patch to demonstrate Voice bug.


  1. Hi, I'm a student who working with Reason. Do you mind if I scrap some of your posts to my blog? I want to traslate it to korean. because you know...I'm that Korean. All the works you've done and been doing are truly amazing. actually I'm shocked. I promise that it will be using only for my studying, only personal and nothing else.
    I'll be waiting for your answer. Bye.

  2. Hi Gonu,

    That's fine, you're welcome to translate it, but please provide a link back to my blog so that your readers know where the information came from. All of my material is licensed under the Creative Commons Attribution ShareAlike license which means you can copy, distribute or remix provided you attribute back to me, and anything you derive from my work (e.g. a translation) must also be provided under the same or similar license.

  3. Thank you for your permission. I'd understand what you've mentioned and I'm sure I'll do that. Thanks again for your generous providing and all the genious works.