Need some quick help from my fellow MS2000 / microKORG users

[midnightmeteors]

Yesterday my Korg MS2000R arrived! My first hardware synth.

I'm super happy about this, and love the sound of the unit. However, I've noticed my unit has a 'characteristic' on the top end / high range that I'll explain in a moment. If this is normal for the MS2000 / microKORG sound engine, then it won't bother me as much. If something's wrong with my unit, obviously I'd like to know since it was listed as 'excellent' condition in the ad.

So here's the quick version - in the init patch sawtooth, it sounds 'normal' and, in an equalizer, has a pretty normal / flat representation in the high end of the frequency spectrum. However, as soon as I lower the resonance (it is raised a bit by default) or change the filter from 12dB lowpass to 24dB lowpass, an audible 'ring' or 'problem sound' starts to creep in. On an equalizer, this is clearly visible around 21,000Hz as a little spike that moves up and down when I hold a note. The sound is somewhat unpleasant when a high note is played, perhaps even more noticable on low notes.

So, my question - has anyone else heard / experienced this with your MS2000, or microKORG? It's possible this is 'normal' and part of what contributes to the (fantastic) buzzy sound of this synth. If someone already knows about this, or would be willing to pull up an equalizer and take a look at 21KHz for me, it would be much appreciated! I just want to know if other units also experience this and it's normal, or if mine needs servicing. With a little help from the community, I can figure this out!

Note - I have compiled sound and corresponding images so you can hear / see what I'm talking about! See those things here:

https://drive.google.com/drive/folders/ ... sp=sharing

Thanks so much for reading, and, regardless of this hiccup, I'm very happy to have my first hardware synth!

[OpAmp]

Hi,

In general, I think your unit is fine.

* You call it a hardware synth, but the MS2K is in fact a virtual analog synth. It is a software synth in a hardware package, allowing you to have a more tangible way to control it via knobs and buttons. But the core of the engine is software running on a DSP. The software engine mimics real hardware, analog synths.

* It's processing frequency is around 44kHz, so it is not that abnormal you may see strange things around 21kHz (around half the 48kHz) because this is the difficult region for software algorithms to keep things clean and away from aliasing.

* You will not hear things above +/-20kHz. Your ears do not pass those frequencies to your brain.

* Pay attention with interpreting results on spectrum analyzers. They use FFTs and if not setup properly you may see ghost frequencies. E.g. for your init patch you say it is a rather flat spectrum. That is not possible. A sawtooth has by nature a decaying spectrum. If I analyze your first sound snippet with Audacity I clearly see the decaying spectrum.

* So IMHO, if the init patch is a single oscillator, low pass filter, cutoff set to 127, no reso, no effects and still hear artefacts, than it must be due to the aliasing in the digital (software) oscillators. And may sound a bit strange. Aliasing adds non-harmonics.

* Leave alone to add the filter algorithms. They may also numerically not that stable or good, adding again extra artefacts.

* Not sure what you did in the 4th snippet, especially noticable. It is like an LFO applied to the amplitude. This is also visible in the waveform. It still could be due to the aliasing. When it generates 2 tones that are close to each other, you will hear the average frequency but with a modulation on the amplitude.

* Is aliasing a degradation of your unit over time? No it is inherent to the software algos used. It would be there at day one. Could the software be damaged? In theory yes. But then I would expect more major issues with the unit.

* I don't have a MS2K. I do have a mKXL, which is in the same ball park. It does not show exactly the same issue as you have, but also suffers from all kind of weird artefacts. E.g. Osc1 Sine: looks clean on the spectrum. I.e. one tone. Osc2 Sine: 1 tone + a lot of harmonics at lower frequencies (like a filtered triangle). The sawtooth shows also aliasing, adding non harmonics. And so on...

So I think it is fine. If you really are looking for pure tones, then this is maybe not what you need.

Have fun

[midnightmeteors]

* You call it a hardware synth, but the MS2K is in fact a virtual analog synth. It is a software synth in a hardware package, allowing you to have a more tangible way to control it via knobs and buttons. But the core of the engine is software running on a DSP. The software engine mimics real hardware, analog synths.

Yes, not true analog circuitry, but "software within a hardware casing". My terminology was confusing. I use U-he Diva and Repro when I desire a closer approximation of real analog synth sounds / behavior!

Regarding the rest of the technical information you posted, there is simply too much here for me to quote all of it. However, your response is detailed and very informative. Thank you for taking the time to write it!

* I don't have a MS2K. I do have a mKXL, which is in the same ball park. It does not show exactly the same issue as you have, but also suffers from all kind of weird artefacts. E.g. Osc1 Sine: looks clean on the spectrum. I.e. one tone. Osc2 Sine: 1 tone + a lot of harmonics at lower frequencies (like a filtered triangle). The sawtooth shows also aliasing, adding non harmonics. And so on...

Good to know, more anecdotal evidence that my unit is likely fine. Yes, I hope to get the Radias one day, another great (digital) synth which shares a sound engine with the mKXL I believe.

So I think it is fine. If you really are looking for pure tones, then this is maybe not what you need.

Indeed. I enjoy the MS / microKORG sound, as it's somewhat unique. But with the 4-note polyphony limitation, and a fair amount of artifacts, it is perhaps better suited to arps and lead lines than large stereo pads or clean sawtooth high notes. Some of the DWGS waveforms are also quite good, and I enjoy the fairly robust virtual patching matrix.

Thank you again very much for your time. This information is great!

Best regards

[OpAmp]

Great! Glad you share the same vision!
The danger here is to fall in an endless discussion about analog vs virtual analog (digital), whether digital synths have the right to exist, whether analog is warmer, etc... Both have pros and cons.

Yes, the Radias would be great. Drum track, 24 voices, modulation sequences, full of knobs, ... However (still) too expensive 2nd hand for me. An R3 would also be nice for me.

Enjoy.