Can I create sweet bell tones using Audio Mod? Is this really FM?

[robst247]

According to the MatrixBrute manual (4.4. Audio Mod):

"When the VCOs modulate other VCOs, it's called Frequency Modulation - FM.
• VCO 1 > VCO 2 adjusts how much VCO 1 modulates VCO 2.
• VCO 1 < VCO 3 > VCO 2 lets VCO 3 modulate VCO 1 or 2."

However, I'm struggling to make convincing bell tones using Audio Mod. Is this feature really FM, or is cross modulation / ring modulation? Most of my experiments with Audio Mod have so far resulted in jarring noise rather than sweet bell tones. 

Can someone please coach me on how to produce sweet bell tones with the MatrixBrute?

[SoundRider]

Of course it is FM ... but you can also generate bell-like sounds with ring-modulation.

Now, making it short ... for FM producing metallic sounds, it takes

1) a frequency ratio of - for example - 2:3, 2:5, 3:2, 3:5 (VCO1:VCO2). Rule, the division shall not result in an integer.
2) the envelopes should be forming like a "pingggg", meaning, very short attack, no sustain, and fitting release

You can also tweak the modulator until you get the feeling that it starts to sound bellish ...

Since FM tends to generate very complex soundshapes from two very simple sine waveforms, it would be wise to start with the most simple waveforms as possible, which would be triangle waveforms on the MB.

[robst247]

Well, I've tried your method (with all the frequency ratios you suggested and various others) and I certainly get metallic sounds. But whatever I try, I don't get what I WANT: a sweet bell tone - like well-tuned brass bells or a glockenspiel - that tracks with the keyboard so that I can make MUSIC with it. What I get hurts my ears and doesn't track with the keyboard. The best results still sound like a drunken smith hammering random metallic objects in his smithy, not angelic carillons. ;-)
   I also have Synclavier V, which easily makes beautiful bells. Modulate a carrier sine with another sine at a non-integer frequency ratio (1.63 works well), modulate the FM modulation amount with an envelope that has a sharp attack and a slow decay and you get beautiful bells. But not on the MatrixBrute. What am I doing wrong? Or is this beyond the MB's capabilities?
  Maybe you could post a link to some presets that you've made which have sweet bell tones.

[DrJustice]

Additional tip for FM and bell sounds: You can get sine waves for VCO 1 and 2, just use the sub oscillator sine on it s own. Set all other waveforms to 0, make sure the sub waveform is in the leftmost position which gives a pure sine, then crank up the sub osc. VCO3 has a sine wave as a choice too. You may want to use the octave buttons to get into a higher frequency range. That's instant bell tones, tweaking the frequency ratios and the FM index as usual. The other waveforms give interesting sounds but not very bell like ones. Adding some LFO to the modulation index, VCA or oscillator levels gives that wavering quality to the bells sounds.

[SoundRider]

Okay understood ... now ... to those bell sounds ... IMO you should NOT use the MB, this may sound harsh but here some thoughts,

Those clean and melodic bellish sounds you are after (like glockenspiel) are best created in the realm of digital FM, why

FM synthesis is highly responsive to the frequency relation between the oscillators or "operators". If only one of the oscillator frequencies goes a tiny bit out of tune, the sound often changes dramatically. Stability of sound requires stability of the oscillators.

BTW ... you mentioned Synclavier, this was a digital FM synth

Now ...

Analog oscillators are rarely very stable and that's nowdays by intension, because this gives us those wanted warm, natural, "analogue" sounds. If we listen carefully to two VCOs of the MB, we can hear those fluctuations, which make for a great analogue sound of this synth. If a VCO-frequency is controlled, like some digiatal controlled VCOs (DCOs), the sound get's cleaner and is also better suited for cleaner FM. But the MB has analogue controlled VCOs with exponential behaviour, which are very sensitive to temperature changes (this is, why we have to warm it up, after all, or recalibrate from time to time) and this generates unstability all the time.

Digital oscillators are very stable, clinically stable sort of. This allows for clean and highly controllable bellish and also wooden sounds (glockenspiel, marimba, xylophon etc). We can insert slight vibrations (noises) up to broken bell like effects by adding a controlled third or fourth oscillators with specific frequency modulations.

To sum it up. The natural fluctuations of the MB create uncontrollable side effects and keep the FM sound changing. The sound get's quite some gritt or dirt just because of the natural instability of the VCOs. Clean bellish FM sounds are not his strength. But I love just that "dirt", which can create rough but melodic sounds

But you can try to play the filters (resonance) in tune (keyboard tracking). The filter give us clean sine like bell sounds.

EDIT: If you are interested in an affordable HW-synth for digital FM, which is providing great sound and is easy to operate ... check out this http://ixox.fr/preenfm2/

I have it since a while, worth every cent ...

[DrJustice]

...
But you can try to play the filters (resonance) in tune (keyboard tracking). The filter give us clean sine like bell sounds.

As mentioned above the oscillators prove sine waves directly. While the (desirable) imperfections of analogue make it hard to get a similar sounding FM bell sound across the keyboard, FM with sines do get the timbre.

[robst247]

OK - thanks. I understand that MatrixBrute won't give me the perfectly stable frequency ratios that are necessary for pure bell tones. Having recently purchased the MB and a Korg WaveDrum, though, I'm not going to be buying PreenFM2 in the near future. I'll stick to Arturia Synclavier, Native Instruments FM8 and Dexed.

If anyone has created interesting MB presets that have a bellish or ringing sonic quality, please post them in the Presets sharing section of this forum.

[DrJustice]

Try this, starting from an Init sound:

- In the mixer, turn off VCO 1, set VCO 2 level to 2 o'clock, send VCO 2 to the ladder
- in VCO 1 and VCO 2, turn down the saw wave fully, set Sub wave to sine (fully counter clockwise)
- in VCO 1, set Sub level to half
- in VCO 2, set Sub level to 3 o'clock, set Coarse tuning to +1 octave (turn it clockwise until the LED lights up)
- in the FM section, set VCO 1 > VCO 2 to 3 o'clock
- in the performance section, set the Octave to +2 (compensating for the fact that we use Sub oscillators)
- in Env 2, set Attack and Sustain to minimum, set Decay and Release to half
- in LFO 1, select sine wave, set Rate to 1 o'clock
- in the Mod matrix, assign LFO 1 to VCA, set the amount to 30  (to get wavering/shimmering)

This should already give you a bell'ish sound. The key is using sines to get that pure sound. Now play around with VCO1 Coarse tuning, increasing it gradually and observe the sounds. Play around with VCO 1 Sub level and/or the VCO2->VCO1 FM control. From here you should be able to get a range of bell sounds. Also play around with the LFO to control that wavering/shimmering effect. You can also apply the filter with an envelope (Env 1) similar to Env 2 to reduce the higher harmonics as the sound fades. If you spend a little time exploring the parameters settings, not least using very fine adjustments to focus on the sweet spots, you should be able to get some pretty convincing bells sounds.

To 'save' VCO 1 for other uses, you could instead use VCO 3 as the modulator, but I find it easier to get at the bell sounds I want using VCO 1 since it offers more and finer control of FM index (controlled by VCO 1 level and VCO 1 > VCO 2) and pitch (both Coarse and fine controls), as well as other waveforms if you want to 'dirty it up'.

[SoundRider]

I'll stick to Native Instruments Massive, Arturia Synclavier and Dexed.

Have you ever tried Native Instruments FM-8? If you have purchased NI Complete, it was in the package ...

[robst247]

Thanks to DrJustice, whose bell-tone method works well. 

SoundRider, I typed Native Instruments Massive, but I meant to type FM8. Yes, I do have it (and loads of other Native Instruments' software), but I haven't delved into it for a long time.

Right now, it's real knobs that I need to tweak and ANALOG that I need to hear.

[robst247]

Here's an interesting preset I just created based on DrJustice's patented recipe for sweet bell tones but with some modifications of my own:

1. Instead of routing directly to VCF2 (ladder), I've put the filters in series and switched VCF1 (Steiner) to high-pass mode. Why? To filter out the disharmonic undertones (lower sideband frequencies) that result from FM, before passing the signal to the low-pass filter.

2. Instead of using a sine wave as the carrier (VCO2), I've used a triangular wave (without metallization) to give a fuller, more complex timbre, more like a church carillon.

3. To further beef up the sound, VCF2 has about 60% Brute Factor (about as much as I could dial in without getting that expensive 'speaker-cones-popping-out-like-Madonna's-pointy-tits' effect).

4. To imitate the metal beater, I mixed in an initial burst of Blu noise. Noise Level is 83% modulated by ENV3, which has only a very short decay section.

5. The echoes rising in pitch (which are only heard in the lower three octaves) are created by the Stereo Delay, with Regeneration cranked up almost to the max. and a medium delay time about 55% modulated by ENV2, which has decay set at about 75%.

6. The VCF2 (Ladder) cutoff frequency is tracked to the keyboard with a positive slope of about 33%.

What do you think, fellow MatrixBruters? If you modify this preset in an interesting way, please post the result(s) here.

[DrJustice]

Nice one Rob - this can be taken quite far!

I played around a bit using some of your suggestions. Very good tip about using triangle for the carrier - that gives much brighter bells with smaller modulation index. I also used both the sub sine and the triangle simultaneously to good effect. Using HP + LP series filtering also gives a lot of subtle shaping possibilities. And the noise beater work very well. And we still have one oscillator more to add, either as modulator or carrier or something else...

I'm getting a huge range of nice bell sounds, from tiny little bells to big heavy ones, and also all other sorts of metallic sounds from the sweetest pings to brutal clangs. Big fun!

[robst247]

Ah, the aural ecstasy of analog tintinnabulations! 

How about sharing some of your bellish presets? I'd LOVE to hear 'em!

Enjoy!
RobSt247

[DrJustice]

Sorry, I haven't saved any... I'm terrible at saving patches (not being able to name patches is bugging me too...).

Anyway, now that we have cracked the bell, so to speak, I'd rather encourage others to use the tips we've come up with to explore this sonic territory - once you have the basic bells going it's easy to be in control and take it in different directions.

Ah, the aural ecstasy of analog tintinnabulations! 

Bellissimo!

[SoundRider]

Right now, it's real knobs that I need to tweak and ANALOG that I need to hear.

I understand this very good.

It's also interesting and great to hear that DrJustice and you got FM tones out of the MB, which you like. I tried myself some patches, which have never been clean tubular bell like sounds, but I love them just for their imperfections.

It's a bit off-topic, but have you tried FM on a modular synth? I use the Verbose "complex oscillator" and this has become my go to tool for creating analoge FM sounds.