The dark sound of Virus, what is the reason and will it apply to signals from inputs?

[Timo]

Not many people realise this, the Analog Boost setting in the Effects section is almost always ON by default with the intensity set to 40, this rounds the sound somewhat by boosting the frequencies at whatever the given Analog Boost tune setting is set to - the default tuning is 32, which boosts the lower-mid freq's.

Remove Analog Boost entirely (intensity = 0) and you get a slightly brighter and more 'digital' waveform.

To see just how much Analog Boost alters the waveforms, see one of my older posts: http://infekted.org/virus/showthread...779#post305779

And yes, given Analog Boost is in the effects section of the Virus, it is applied by default to any external audio that is injected into the audio inputs on the Virus too. So remove it from the signal path entirely by simply turning its intensity down to 0 for any given patch.

But that is not all.

The Classic oscillators are less bright than they should be, I believe Access Music, at the time, made them less bright to reduce obvious aliasing at higher frequencies.

They rectified this with Hypersaw for the TI, giving you the choice between the Hypersaw and Classic saw algorithms (including pulse when using the Sub Osc for hypersquare).

So use Hypersaw instead of Classic for higher frequency content.

I did a test on this just a few weeks ago. The differences between Hypersaw and Classic saw are clear to see:





Single instance of Hypersaw (1 saw) vs. 1 x Classic Saw using TI Snow. C4 key used (262Hz fundamental), Analog Boost intensity set to 0 (in Virus effects), RMS level matched. Monitored and recorded at 88.2KHz/24-bits via Motu Traveler soundcard.

Both pics are the same, they just show the content using different scales (top pic linear, bottom logarithmic).

Shows how much flatter and brighter the harmonics are at the top end of the Hypersaw over the Classic Saw on a like-for-like basis. Pretty much identical until around 12Khz, then they separate, widening to approx 6-7dB difference at ~20KHz before both top out at ~22KHz.

However, there are times when using the Classic saw is necessary. The Classic saw offers more control over the oscillator than Hypersaw does, for example, such as being able to specify init-phases, and is generally more predictable and less unruly. For more info on this, see my Hypersaw vs. Classic video regarding phasing at note-on: http://www.youtube.com/watch?v=YUHC8E1YIro

Lastly, if you want a higher fidelity output, use the analog outs and a good external soundcard instead of using the Virus USB audio bus. The analog outputs on the TI are balanced 192KHz 24-bit (the Snow isn't balanced, though), while the TI USB is only 44.1KHz 16-bit.

[oli@bass]

Hey Timo, thanks a lot for your detailed explanation.

Originally Posted by Timo

And yes, given Analog Boost is in the effects section of the Virus, it is applied by default to any external audio that is injected into the audio inputs on the Virus too. So remove it from the signal path entirely by simply turning its intensity down to 0 for any given patch.

Great tip. The "Character" section is easily forgotten. And it also provides some characters which remove bottom, or add top end to the sound. But it doesn't sound like just an EQs. Some settings even broaden the stereo width or simulate a rotor cabinet. Maybe the Virus' "Character" effect is the very first application of the Kemper Profiling Amp technology?


Anyway, I've never thought that the Virus sounds dull or is incapable of producing sparkling or crisp sound (which is proven by your diagrams). But looking at a spectral analyzer, I found that FM of higher pitched notes does not produce all the partials you'd expect, and I think that this is really to prevent excessive aliasing.
So it might really depend on the type of oscilllators, filter settings, and effects, how much top end the Virus produces.