Update: Thought I'd clarify my point below. I believe the intent of the comparison was simply to see if an Evolver could cover the MS-20, rather than a filter A vs. filter B comparison? It's an interesting line to cross when you think ab out it. Anyway, take my comments below as just that... comments in general.
Kind of an odd comparison as the two filters are completely different, but there it is. Title link takes you there.
Why this comparison is odd:
The Evolver is a product of Dave Smith Instruments. Dave Smith was the man behind Sequential Circuits. He is responsible for the classic Prophet 5 and Prophet VS. The Evolver is an evolution of these two synths. It has two digital oscillators containing the Prophet VS waveforms and it has two analog oscillators similar to the Prophet 5. The filter is a custom Curtis chip. The Prophets had a Curtis chip as well, but a different model. Regardless, if there is any filter to compare the Evolver to, it would be the filter on the original Prophets. They are very similar. The Korg MS-20 on the other hand is a discrete analog filter and sounds very different not only from the Evolver and Prophets, but also from the Minimoog Ladder filter and most Roland filters including those on the 303, Juno, and Jupiter series. So.... take these comparisons with a grain of salt. What you like may reveal more about what filter you like better between a Moog, SCI Prophet, or Roland.
BTW, it's commonly thought that what makes a Korg MS-20 as far as sound is it's filter. That thing can strip paint off a wall. If you want the filter without the price, check out the
Frostwave Resonator. It's a clone of the MS-20 filter, I've never heard anything to the tune that it's close but not quite there like most other clones (read this as it is the same filter), and it most definitely screams. This is the Korg MS-20 filter.