Acid On A Budget

We’ve been having lots of fun with the new Digital Filter and we thought we would share some of our findings with you. For those who are still championing the sub-genre affectionately known as Acid House, we have some good news for you. With a few simple elements from Reason plus the Digital Filter, you can create your very own TB-303. Let’s get started.

• First, instantiate an instance of the Subtractor Analog Synthesizer, this will act as our main voice. In fact, the very first preset “Bass Guitar” is just what we are looking for to achieve this simple but classic sound.


• Next, connect the Digital Filter and also add a Spider CV Merger & Splitter. Since the Digital Filter supports Note and Gate CV inputs, this will be able to accurately track the output of the Subtractor just like the TB-303.



• Next, instantiate the Matrix Pattern Sequencer and make sure that the Note and Gate CV Outputs are connected to both the Subtractor and Digital Filter (using the CV Splitter). Though this is not visually like the original sequencer, the Matrix is fully capable of generating both discrete and continuous note events. If you’re not that familiar with the Matrix, for instance you can hold down Shift while drawing Gate information to add continuous steps, release Shift to draw discrete steps. For more information about the Matrix, check out this awesome article from Sound On Sound.


• Lastly, you might notice that this sequence does not glide between notes. Though this feature was more configurable with the TB-303 you can achieve a similar sound by increasing the portamento control in Subtractor, we recommend a value of 90 as a starting point.


Here are some sound samples that demonstrate this approach:

And we have created a Combinator for you to explore. To start, try flipping the State (HP/LP) switch to HP and experiment with sounds not previously available from the TB-303. Also, we set the order at an 8-pole filter since that sounded best but you can find a more subtle sound with a 2- or 4-pole filter (as in the original) as well as reach beyond with a 12-pole filter, and everything in between.

• Download TB-303 Clone Combinator