Tremolo with Thor in Combinator - Scaling issue?

[Ezmar]

So I'm following this tutorial (https://www.reasonexperts.com/tremolo-e ... son-3.html) for using Thor as a tremolo processor, since there isn't a standalone tremolo effect unit, which is a bit puzzling to me, but whatever. I'll start at the beginning here.

I have my Rack set up as so.

Front:

Reason Tremolo front.png (534.94 KiB) Viewed 618 times

Rear:

Reason Tremolo rear.png (708.22 KiB) Viewed 618 times

The yellow cable on the rear is an oscilloscope to monitor the LFO2 output. All indications show that it's rock-steady. The issue I'm having is that when I alter the scaling in Thor's Mod Matrix (The value which is 81 in the picture), it doesn't seem to do what I expect. Instead of simply altering the amplitude of the tremolo modulation, it seems to be doing some strange things with the rate. While the rate of the LFO itself isn't changing, at 50 scale, the only difference from 100 scale seems to be that the rate is halved. The depth doesn't seem much different, if at all. At around 75, there's a strange lopsided beat to the tremolo, where one side is shorter and shallower, and the other is longer and deeper. This happens with both mono and stereo, and regardless of how I alter the scaling. The Modwheel also doesn't appear to have any affect in Dexed directly, so that's not the culprit either.

So the scaling isn't working correctly at all, and the depth of the modulation isn't as much as I would like, even at maximum. I may just try a different machine for the tremolo, like Synchronous or something, but I'd like to know why this isn't working for future reference. I've tried to explain the best I could here, but if something's not clear, please feel free to ask.

Thanks in advance!

EDIT: Upon further investigation, the actual pulse of the tremolo is double the LFO rate as shown in the oscilloscope. This leads me to believe that it has something to do with where the "zero point" is considered, since it seems to simply be following the magnitude of the wave from center. Not sure what I can do about this, exactly, but it seems that it will be an educational experience either way.

[guitfnky]

apologies since I don’t have the time to go through that right now and give a proper response, but you could use a Pulveriser. there should be a tremolo patch, or you can reset the device and set it up yourself fairly easily. wet/dry can control the depth.

[Ezmar]

That's probably what I'll end up doing, though it still seems bizarre to me that there's no simple tremolo effect Routing a Pulsar or similar to a CV input can be a little finicky.

I'm still curious as to what's causing the strange behavior with Thor, though.

[Catblack]

I don't know if this article helps with what you are asking about, but it may.

http://offwhitenoise.blogspot.ca/2009/0 ... mount.html

[selig]

I believe this issue is more about using a bi-polar source (LFO2). If you substitute the Global Envelope (set to loop) you get very predictable results, but that's not ideal.

The solution is to convert LFO 2 to uni-polar, something Thor can easily do.
Leave the Combinator set as it was, change the "Scale" source from LFO 2 to CV In 1.
Set Rotary 1 to "124".
Then add two more rows to the Mod Matrix as follows (to convert LFO 2 to uni-polar):

Screen Shot 2018-04-24 at 4.11.48 PM.png (67.64 KiB) Viewed 569 times

Remember to connect the CV on the back panel as below:

Screen Shot 2018-04-24 at 4.11.57 PM.png (274.25 KiB) Viewed 569 times

That's it! (remember to leave Rotary 1 set to "124")

[Ezmar]

I believe this issue is more about using a bi-polar source (LFO2). If you substitute the Global Envelope (set to loop) you get very predictable results, but that's not ideal.

The solution is to convert LFO 2 to uni-polar, something Thor can easily do.
Leave the Combinator set as it was, change the "Scale" source from LFO 2 to CV In 1.
Set Rotary 1 to "124".
Then add two more rows to the Mod Matrix (to convert LFO 2 to uni-polar):

That's it! (remember to leave Rotary 1 set to "124")

I've since replaced it with a Pulverizer for this particular patch, but it's always good to learn a little bit more about this stuff. I figured it had to do with the polarity of the wave, so it's good to know how to get it to output as uni-polar. My previous experience with cv routing comes from the Modular Synth in Caustic, which has a convenient switch on the rear panel of the LFO module, which is much easier to understand.

Thanks again!

[Lempface]

I believe this issue is more about using a bi-polar source (LFO2). If you substitute the Global Envelope (set to loop) you get very predictable results, but that's not ideal.

The solution is to convert LFO 2 to uni-polar, something Thor can easily do.
Leave the Combinator set as it was, change the "Scale" source from LFO 2 to CV In 1.
Set Rotary 1 to "124".
Then add two more rows to the Mod Matrix as follows (to convert LFO 2 to uni-polar):

Screen Shot 2018-04-24 at 4.11.48 PM.png

Remember to connect the CV on the back panel as below:

Screen Shot 2018-04-24 at 4.11.57 PM.png

That's it! (remember to leave Rotary 1 set to "124")

Selig is awesome, just saying!