If you’re looking for something to beef up your Sub 37 even more, this is my recommendation: The Waldorf 2-Pole analog filter.

Waldorf 2-Pole Analog Filter

Waldorf 2-Pole Analog Filter
(Photo by Frank)

The Waldorf filter sounds quite different from the Moog ladder filter, and offers different modes, too. Especially useful is the Highpass mode: It helps fit the Moog into the mix if you don’t want it too bassy. But the other filter modes should not be underestimated, either, and are able to create surprisingly fresh sounds if you provide them with enough harmonic content. The resonance goes up to complete self-oscillation and is as fun as it is dangerous for the speaker if you’re not using a limiter. The real fun begins with the 2-Pole’s distortion capabilities, though. Overload the input stage, use the rectifier to create additional harmonics (up to the point where you essentially pitch shift the signal to a higher octave), or use the post-filter overdrive to make it scream. All three kinds of distortion can be combined and they sound absolutely delicious. Additionally, there’s an LFO that goes from very slow up to high audio range, as well as a threshold-based trigger feature that can give you e.g. a funky auto-wah.

The flavours the 2-Pole can create have absolutely blown me away, and it’s a breeze to use. Whether you’re aiming for acid leads, aggressive dubstep sounds, classic overdriven leads, or just some subtle saturation, I highly recommend you give the Waldorf 2-Pole a good spin!

Sound demos

Here are some examples of the 2-Pole’s sound. The Sub 37’s Feedback and Multidrive features were not used, and the Sub 37’s filter was always fully open with no resonance.

Filter Types
First the Sub 37 output without the 2-Pole, then three successive filter sweeps (Lowpass, Highpass, Bandpass) with rather high resonance.

The same as above, but with a combination of overloaded input stage and post-filter overdrive.

First the Sub 37 without the Waldorf 2-Pole, then the same sequence with the 2-Pole’s Threshold-based Envelope trigger. First with varying Attack values, then the same with Decay. This is not the Sub 37’s envelope!

First the Sub 37 without the Waldorf 2-Pole, then the Lowpass filter with LFO comes in, sweeping from minimum to maximum rate. First in “Slow”, then in “Fast” mode. This is not the Sub 37’s LFO!

Distortion Types
First a little melody with just a tame lowpass filter and LFO from the 2-Pole. Then the same with saturated input stage, then with lots of post-filter overdrive, then with about 60% rectify, and finally with a combination of all three.

Self Oscillation
By setting a very high resonance value, the 2-Pole starts self-oscillating, essentially turning it into an oscillator (possibly even controllable via the Cutoff CV input, making it an instrument). Here’s a sweep from minimum to maximum, and then back to minimum frequency, the latter including some LFO fun. What you’re hearing is the 2-Pole alone, with no input signal. Careful with your speakers and ears: Extreme frequencies!

A basic sequence from the Sub 37 with some knob twiddling on the Waldorf 2-Pole.
Spiced up with a little reverb and delay from the Lexicon MX300.