What is it with this Virus sound?
 

After ten years of ignorance, I got more interested in the Virus. I have to add, that I played with one of their first prototypes, back in the days, and that thing was buggy. That turned me off and I end up buying a NL2 that served me well over the years. However, the TI grabbed my attention with their extended sound possiblities, e.g. wavetable, grain.

Since there were some reported problems with the TI - and I do not really to update my equipment every week - I decided to go with a used Virus Classic. I thought this way I can evaluate the Virus sound and see if a bigger investment is needed in form of TI.

After weeks of programming I come to the realization that this is a love/hate machine. I love the sounds I get out of the board that easily can keep up with some of the older Roland stuff I owned many moons ago. Nice PWM basses, smooth pads, and all in stereo! However, when I try to do other things, mainly in the higher pitch range, things are getting ugly. For example, higher pitched sounds (whatever sound you choose), FM sounds in middle to higher pitch, saturation stage (at middle and higher pitch). All is full of aliasing.

Aliasing must not be bad, e.g. I love those PPG sounds that sometimes live off aliasing and be smoothen out by the filter. But I cannot get a control over the sound with the Virus filter. I made a test and fed the Virus filter with NL2 Oscillators at very high pitch. I did not notice any aliasing with the filters, so it must be the oscillator bank.

I understand that Access is cramping alot of code into this little DSP, gives us plenty of polyphony, efx, and soundpossibilites. But the fact that I cannot use it for higher pitched sound pretty much destroys the ONE KEYBOARD does it all feature that Access is trying to push on us.

Another annoyance is that when choosing the saturation stage or the distortion effect, the effect is audible even the intensity is set to 0. That is bad since it makes the blending of a distortion efx into a clean sound impossible (the K-Station is better in the case).

I guess I will stick with my classic for now, because the software is rock-solid and the sounds are great as long as you stay in the boundary of that synth. I managed to get one higher pitched sound without noticable aliasing by setting the phase of the oscillators. Any other ideas, beside cranking up the EQ what doesn't sound nice to me either. Does the TI is better in this regard??

no one synth can do it all... yet. As i'm sure you know, all synths sound different. the virus and nl2 are both "edgy" synths with a kind of harsh sound to them. a moog sounds "sweet". but neither can cover all the bases. I like my virus B and nl2, but i don't use them for lead sounds. I too am curious if the aliasing has been improved on the TI. I assume it has, but to what extent.

Must say the distortion or filter saturation at values of 0 were one of the first things I noticed about the Virus (Indigo v1, the same engine as a Virus Classic) when I got my hands on it, which I found quite strange.

There's a huge difference from having a value of 0 compared with the distortion/saturation being completed switched off, so it's by no means subtle.

My hearing's a bit shitty so don't notice the aliasing on the top end so much, but I do notice it when Sync or FM is used at the higher freqs.

Welcome to the forum, btw.

In the higher range, I always tend to get a headache because of the aliasing that is even worse when playing more notes. I am controlling the Virus via a NL2 keyboard and rule of thumb so far is that I keep the pitch of the Virus at 0 or below. That seems to work. If I had the Virus KB, I guess most of the sounds needed to stay at -1. Like I said before, in that range the virus sounds great!!

With the saturation stage and the distortion effect is a bummer. But I guess you can live with it. The effects are great also for processing my NL2 (even at higher pitches no aliasing to be heard).

Another cool effect I really like is to sync and detune the oscillator down! With the classical waveforms there is no difference but with the wavetable you get changes in the waveform. Never thought of that until I took apart on of Howards sounds apart. I wonder if this works the same way on my XTk?

Now, looking at the TI, I guess what mainly changed is the polyphony and the amount of efx. I doubt they worked on the aliasing otherwise the specs would not been suped up that much. Can anybody confirm this?

Anyway, pretty happy with the Classic and that keeps me busy for a while.

Hi -X-,

Regarding aliasing: I gather you've never heard a V-Synth FM aliasing? The TI is pure silk compared to that. I'm intrigued with the Nords if they don't alias.

I think if you've heard actual 1970 analog equipment, you're expecting a different sound. Much of vintage oscillators rounded the waveforms (reduced harmonics) at higher frequencies. A saw wave often had a slow reset which noticeably affected the waveform at high notes, the TI doesn't do this. So to some extent, you are hearing more harmonics in a TI wave than analog. This may seem unpleasant to you and has a similar tone to aliasing, although the TI is not a bright sounding instrument.

But even if you're not comparing the TI with analog, I hear alias-like sounds with my imperfect hearing even with acoustic instruments. I genuinely hear inharmonic artifacts in some frequencies. I think its possible for people to experience this and mistake it for aliasing - not everyone has golden ears but we sure all like to think we do :)

Aliasing should be verified by looking at the waveform rather than hearing it. And even if it is there, it doesn't detract from the wonderful sounds only a Virus can make.

Cheers,
B

the lack of aliasing on the NL2 is pretty good. acceptable levels for my use. most new V.A.'s are much improved in that department. I have a creamware minimax asb and aliasing doesn't occur until you play notes higher than most people would find usefull. (can't compete with the virus for fat poly patches though)

just wondering at what note\octave do you start to hear the aliasing?

Ive always found the higher notes sound a little strange on the virus and i normally tend to layer the higher riffs with another synth. leaving the virus playing lower\mid range

Sounds like listening fatigue. Often caused by digital reproduction of sound into a less than perfect audio chain and particularly with some monitors and headphones with metal tweeters/drive units with ave more of a tendency to resonate badly than the softer sounding silk or similar tweeters.

Distortion and/or aliasing in high frequencies certainly contributes to this by adding a whole load of extra atonal frequencies.

Like I said before, when triggering the virus with an external keyboard, I can hear aliasing very clearly when putting the Virus to 0 (octave/transpose) and the play the fourth octave on my NL2. I guess that would make it C4 and up?

I think the NL3 run at an internal sample rate of 96K - that would put the main aliasing tones well outside audiable range.

I remember a recent discussion on the Korg forums about odd tones on the Radias. Turns out there is actually a quirk in OSC 2 in that it simply doesnt produce such a perfect waveform as OSC 1 and the extra high frequency tones come from that - and if you listen carefully there are definately harmonics and not just unrelated tones.

So its worth checking out the waveforms in a wave editor.