Vadim has decided to release the Core structures that he created for the tutorials accompanying his DSP articles on the NI Wesite.

1) "Preserving the LTI system topology in s- to z-plane transforms"

2) "Frequency-scaling of discrete-time LTI system responses"

3) "Computational optimization of nonlinear zero-delay feedback by second-order piecewise approximation"

http://www.native-instruments.com/index.php?id=dsparticles&L=1

The three ensembles allow to directly try out the improvements archieved by the described methods.

In a nutshell: it's a way to get high-quality filters without oversampling.

For the third article we have added a mp3 audio demo. It showcases the behaviour of four types of filters running at 44.1 Khz samplerate.

0:00 min: Ladder
1:35 min: State Variable LP2
2:40 min: State Variable BP2
3:50 min: State Variable HP2