Sine wave on A4

Elektron Gear Analog Keys/Four
#16

That doesn’t really make sense. If you had a sine wave oscillator it wouldn’t automatically cause higher frequencies to be attenuated, it would just create a peak at its own frequency. Much as I like self-oscillating filters, I still want the attenuation functionality…

Of course you wouldn’t need to do any attentuation if your synth had only a single oscillator since with no harmonics there’d be nothing to attenuate, but the A4 and most other synths have 2 or more oscillators. Even synths like the Minibrute, though having only one oscillators, get a lot of different tones by using it to drive multiple shapers so you can get some timbral complexity.

#17

it would add a bit more price to the machine too. likely the most influential reason for not including it.

plus its an elektron machine. the not so obvious route. its all about the tweaks and tricks :stuck_out_tongue:

#18

My understanding is that pure sine waves are difficult to engineer with analog oscillators. It would probably be somewhat sine like over some bandwidth but would be unreasonably non-sine like in other regions.

I have used F2 in 12dB high-pass tracking self resonance has a sub oscillator with some success.

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#19

This is the main reason they are not included in analogue synths. A perfect sine is something of a theoretical construct. They don’t really exist in nature. Most analogue synths that do offer them go about it by pre-filtering a triangle wave. Hence terms like “triangle-core” when referring to how an oscillator is constructed. I’m pretty sure I read somewhere that the A4 uses triangle core oscillators… or am I imagining that

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#20

Again all this stuff is true, In the tag line:

The Analog Four is a polyphonic analog synthesizer with state-of-the-art digital control.

Not sure but couldn’t the DSP route a sin wave to the oscillators?

Is my thinking plain wrong? a PipeDream? or Stupid thought?

#21

Yes, a digital control could look up sine wave values and control a voltage level. Or an analog sine wave oscillator could be made. But both of those methods involve extra complexity for the manufacturer compared with generating voltage ramps or switches between two levels, while any of the other methods listed in the thread can produce a sine without additional components or control features.

#22

Been trying out some of the tips here, found the ideal for DnB sub-bass to layer your sounds:

2x pulse waves (with OSC 1 tuned & detuned to -64, OSC 2 tuned to 0 and detuned to -64 with a 20 cent sub OSC)

Both are filtered pretty low, but high levels of resonance in both filters, filter 2 being in -12dB mode and envelopes to taste

Had a problem for a while where the lowest notes would cut off and would take the bass sometime to recover. After much searching turns out it was having a -10 cent sub. Might be beating or phasing I have no idea, but that sorted it.

Having a -20 cent sub might be in the infrasonic range, but it moves a hell of a lot of air! :smiley:

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#23

What’s a 20 cent subosc?

#24

I assume he means 2oct sub.

#25

Here’s a few pics I took using my ever handy O’Tool scope.
Perfect for this type of business.

Straight triangle wave:

Straight_Triangle.JPG1224×1632 561 KB

Same triangle through a low pass filter (cutoff 50 per cent, no resonance):

Sine_1.JPG1224×1632 518 KB

Same again (bit more cutoff, no res)

Sine_2.JPG1224×1632 549 KB

You lose quite a bit of gain as you trim the cutoff. But I guess this is down to the kind of low pass filter that you use. Sines made like this are perfect for sub basses. They just need to be tuned nice and low :+1:

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#26

The gain loss is all according to plan (aka Fourier’s theories) - as you decrease the cutoff, you are filtering out the higher harmonics of the triangle wave, and therefore the amplitude of the signal is decreased.

http://beausievers.com/synth/synthbasics/#triangle

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#27

I do! :slight_smile:

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#28

Concerning the bass thing: Try the Multimode-Filter in Peak mode with a keytracking of 100% and find a sweet spot in the bass. Afterwards a bit of overdrive can make the sound even thicker. Filtering out most of the overtones with the 4 pole in advance gives very strong sub basses.

Other solution: get a monomachine :wink:

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#29

Keytracking at around 32 is closest to matching the filter tracking to the keyboard. At 64 the filter frequency will change faster than the note (don’t know the correct terminology).

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#30

ahhhh yes forgot I have keytracking set to +32 on both filters :slight_smile:

#31

On the A4, a parameter value of 32 will give you 1:1 or “100%” keytracking where going up or down one octave on the keyboard will also make the cutoff frequency go up or down one octave. This is the setting you need if you want to tune the self-oscillation of the cutoff point to the notes you’re playing on the keyboard.

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#32

very nice, when I did my “sine-like” patches with filters, I used an oscilloscope to create one with sub 1 octave down and one with sub 2 octaves down…that’s the only issue going the self-oscillating filter route, you can’t just pick a logical number on the filter cutoff, you have to tune it

Analog Synth, Sinewave lacking and SUB-Bass Tips & Tricks
#33

Yeah that O’Tool scope is a great module. Really handy for tuning patches. Has several different modes. One is like a guitar tuner. It displays note values, frequency (Hz) and Voltage for any incoming signal. Has two inputs so you can track two oscillators at once. Plus it looks cool

#34

i guess it would be really easy for elektron to put an extra digital sine wave osc. as far as i remember noise is digital, and there is pleanty of free space on that page to have a sine wave too :slight_smile:
maybe one more thing for a next update whishlist?
best
niko

#35

If they are going to add a digital sine wave, they my as well add a whole heap of other waves as well like the DigiPro on the MnM.