Aliasing in ANA-2 distortion FX

Plugins ANA 1.5
1

Hi there!

The first thing I’d like to note about ANA 2 - it has an outstanding sound: extra clear, solid, rich and fat at the same time. With most synths at the market fat=dirty. With ANA 2 not! Especially with ANA’s FM quality which is really great!!!

That’s why I was so surprised to find that ANA’s distortion FX have NO antialising at all (and sound accordingly)! Nowadays there’s hardly a few wave shaping processors out there which don’t use 4…16x oversampling for aliasing suppression.

Think it’s a critical thing that makes ANA’s distortion FX and overdriven filter modes useless if you like to retain ANA’s brilliant crisp sound. Since adding non-oversampled distortion makes the sound “cheep” and dull.

Hope this could be fixed in future versions. And yes: oversampled shapers are really CPU-hungry. If used in VCF (“drive” pot) it may double the CPU load per one voice. So maybe it would be reasonable to make the oversampling feature user checkable. But the ability to use antialised shaping is must-have feature for the VSTi in 2019, IMHO.

Here is the spectrogram for sweeping sinus and use of ANA’s roly filter with high drive.

Look at the ‘beard’ of ghost reflections hanging down from Nyquist frequency which in fact
is a sonic dirt that never present in real analog things and should be suppressed.

2

The same with external shaper (2x oversampling mode)

the ‘beard’ is less bright

3

The same with external shaper (4x oversampling mode)

“ghost” spectrum lines almost invisible!

4

Thanks for the detailed feedback!

i’ve made a note of it :slight_smile:

2 Likes
5

Hi! I’ve recently purchased ANA-2 and I’m really happy with it in my real commercial work! The sound of waveform oscillators (1-3) is really great.

But dealing with sampler oscillators (4-6) was not as painless. Once I had tried to pitch slightly up a tambourine sample I found that ringing metallic sound turned into dirty low-pitched hiss. This got me making a new aliasing test.

Now the sampler oscillator was investigated. I had generated 5kHz harmonic sample and pitched it sequentially by 1 half-tone 7 times up and then 7 times down from the basic tone.

The result is here:

it’s not terribly dramatic and maybe can be considered as good for mid frequency range sounds. Kontakt under ‘normal’ interpolation mode gives just slightly better picture:

But high pitched sounds degrade significantly. And I think it would be so nice to have some “HQ sampler mode”. Like Kontakt’s “perfect” one, that gives a far more natural picture: