I’ve employed a technique that yields a similar result in this track:
Basically, it involves reverberating the kick with a long tail, then band-pass filtering the reverberation down to around 30hz thru 50hz, then giving the result a sharp Q EQ boost in the same resonant frequency as the kick.
You get the sub bass to play off the kick by side-chain compressing the reverberation heavily, with the kick as the key input.
That way when the kick hits, the sub bass completely gets out of the way.
The sub bass serves as a heavy low end extension of the kick, free of attack.
There is a reason we didn’t hear bass this huge until DAWs became commonplace in electronic music. It can be somewhat involved with dedicated hardware. To do this with Rytm you would have to utilize the individual voice outputs (or Overbridge multi track outputs), a band-pass filter unit, a reverb unit, (possibly) an additional EQ, and a compressor with a key-type (not fx loop-type, a’la RNC/RNLA) side-chain input to compress the reverberated sub bass.
If you really want to get the sound out of your Rytm for live stage purposes, I suggest setting it up in a DAW with Overbridge, and then sampling the sum of the kick and the reverberated sub bass, and then importing that into your Rytm as its own, sample based kick track.
It’s a process, but more than worth it.