Recommend a "visual" synth to help teach DSP concepts?

[Elektronisch]

Serum

https://www.youtube.com/watch?v=5kdXo6rXL74

[Michael L]

As Black Winny says, modular makes the most sense because you can start with one simple object -- an oscillator-- then filter it, see how the sound and waveform change, then add another object. Very clear and uncluttered.

[Razzia]

99% Serum will do a good job teaching students, talking from my own expierience.

im surprised some people even suggesting modular, its quite backwards. I remember my friend over 13 years ago suggestested exactly the same, Reaktor. Most stupid advice to give for a beginner. Really its stupid, if you are suggesting that, give some critical thought on your suggestion, because you are giving this as as a learning tool to a person who has no general overview of what synth is or what module do. And how can you learn about those if you first have to learn the modular program and to understand that even to get a basic sound you have to do some backpanel routing

+1 for everything basically. Serum and Pigments are visually the most illuminating for a beginner. And Pigments might be a bit too busy compared to Serum.

Regarding modular... About five years ago was when I went from just kind of noodling with synths to actually learning sound design. Reaktor 6 came out several months later and everybody was buzzing about it. So I checked out Blocks or whatever the freebie was called. And I was absolutely f**king lost. Even now I have to think a little bit about how I want to do things with a modular synth. Not because it's hard but because it introduces extra steps that I only have to think about when i use modular.

[Elektronisch]

As Black Winny says, modular makes the most sense because you can start with one simple object -- an oscillator-- then filter it, see how the sound and waveform change, then add another object. Very clear and uncluttered.

Before doing that you have to learn modular, meaning more information then you actually need at the beginning, dont see how it makes more sense to use instead something like Serum where you can do things with just a click of a button and add osciloscope with spectrum analyzer at the end.

[Michael L]

The OP has a very specific concern that his students don't really viscerally "get" what a filter does, and struggle with understanding what the frequency domain is intuitively. Two modules + display is simple.

[Unaspected]

As Black Winny says, modular makes the most sense because you can start with one simple object -- an oscillator-- then filter it, see how the sound and waveform change, then add another object. Very clear and uncluttered.

Absolutely. A synth will help to teach synthesis but won't tell you anything about DSP - which is all about number crunching.

If teaching synthesis, then I would start with a very basic subtractive synth (none of the current powerhouse synths) - of which there are plenty of free plugins to be found in the KVR database.

I do agree with Elektronisch with regards to Reaktor as it is rather clunky and does things its own way. I love Reaktor but working with arrays is no where near as simple as PureData makes it. The other advantage of PD is being able to export code to C++ -so it is a great learning tool for DSP. Oversampling is also a breeze in PD, whereas Reaktor requires some work in this area - though, you can, of course, design polyphase filters in both environments.

The ideas from Andy, Peter and Unaspected are obviously the best.

And the remark made by Unaspected ("Indeed. Any environment like that.") is certainly the most important that I've seen in this thread.

Naturally.

Because yes, the best way to learn correctly the rudiments of the synthesis in a school is to learn to make oneself some little synths by building them module after module, and learning to build the modules themselves. With all the experiments on modifications, additions or deletions of wires, adjustments of internal parameters, smart architectures, smart organizations of GUIs, etc.

There are several offers which fit for this purpose:

• Synthedit
• FlowStone
• PureData
• MUX
• The Tangle
• Etc.

Not only they are fully modular but in addition they provide the bricks to make ones own modules with their relations, their parameters, their monitors, etc. All visually to let even the less clever students still follow and enjoy (considering that true languages as C++ and Juce for example are for next years and for those who will fully find there a vocation). Only PureData above is already something rather mathematical. The others are almost totally visual environments with bricks, wires, and parameters.

Things as Reaktor or Bidule are awesome also... but much more expensive for one or two dozens of licenses, and having tons of elements which may disturb the rookies they are certainly too much complex for first years students at school.

Had to quote the list to pull those links onto this page of the thread so they're not lost to anyone.

[BlackWinny]

[Mutant]

Helm.


Advantages: free, open source.

[gentleclockdivider]

ONly a modular will give you a complete picture ,because individual components can be analyzed and displayed
The posted examples of helm and serum only shows osc and filter shapes .
When teaching dsp an how a synthesizer works , the pupils need to understand the basic differences between ac and dc
What does an adsr actually do , it mulitplies it's dC signal with an ac signal ( oscilator ) , by pluging these individual components into an osciloscope one can actually see what it does in the time domain .
A spectrum analyzer would show them how osc's are represented in the frequency domain , what partials are etc .
Same goes for adding constant values to modulators etc

So if you don't want to spend money , VCV rack

[Tj Shredder]

Helm.

Advantages: free, open source.

Disadvantage, you only know the connections if you know them already and then you don't need to learn...
As said before only modular can help. If you open the Grid, you'll immediately grab what's going on. Helm has already too much in it, for the topics purpose its useless...
If it has to be free, VCV is fine, but the sheer number of available modules is overwhelming. Though a teacher can easily filter the relevant ones...
Showing FM in VCV is not easy, in the Grid it is btw...

[crimsonwarlock]

If it has to be free, VCV is fine, but the sheer number of available modules is overwhelming.

That is only if you choose to install them. Going with the VCV Fundamental modules only, gives the perfect base for learning synthesis.

[ztrauq]

I'd also mention StageCraft Addiction Synth if you're looking for a synth plugin with visualization of the different characteristics as they are played (osc, filter, envelopes, etc.).

[zzz00m]

The fastest (taking just a few seconds), easiest, way to visually demonstrate the effect of a filter using a DAW is to insert any subtractive synth capable of basic waveforms, and set the patch to init with just one active oscillator set to something like saw, square, etc.

Then insert an oscilloscope plugin such as the free Melda MOscilloscope on the synth output and observe the wave as you adjust the filter cutoff, filter type, etc. You can arrange the two plugin windows in about the same space as a rack modular would take.

Alternatively the VCV Rack suggestion might be the best way to demo the filter effects with a few modules all in one place, but it might take a bit longer to set up the first time. The free Surge Synth now has modules available for VCV Rack: https://surge-synthesizer.github.io/rack_manual/

I haven't tried the Surge modules yet, but if you already understand the Surge Synth UI, it might offer a head start with a few basic modules that are somewhat familiar. Then just patch in the scope, and play with the filters.

I am not aware of any synths that have a built-in way to display their final output waveforms live. So as far as I am aware the two options are either a scope plugin in a DAW, or a scope module in a modular rack.

VCV Rack with scope using default modules:

[faxinadu]

i like to teach with flowstone.

vcv is also a great option.

[AnalogGuy1]

Thanks all for the many responses, both publically posted and for quite a few PM's. I should have been a bit clearer, since many of the responses deal with good ways to teach synth patch design. I'm not teaching a class in synth design in any way; I'm teaching a class that deals with classical digital signal processing: DFTs, DTFTs, Z-transforms, IIR/FIR/matched-filter (time-domain) filter design, and general topics in signal analysis in 1 dimension and a bit of 2D. The math is all there in spades; I'm using a text that goes well into the graduate level topics of multirate sampling. No synths involved at all, per se, - I just think that a short synth demo might provide some aural intuition. My lab assignments are all pretty heavy into signal processing programming using various real-world data (from voltage/optical/pressure sensors, sunspots, electric power variations, gravitational waves, stock market data, etc.); only one assignment involves sound, and for that they program their own filters in Matlab and C++.

What I hope to find is a synth that, in a single 3-minute demonstration which I control, gives an intuitive feeling to students the difference between time-domain and frequency-domain effects, using as examples a synth that shows, in an evolving manner, time-domain signal shape and frequency-domain filter effects, and what resonance does (i.e. the effects of pulling a system's poles in the direction of the imaginary axis).

I'm aware that I can put a scope VSTe on the VSTi signal chain; I've played keys in an actively-gigging covers band for almost a decade. But the frequency resolution of the spectrogram is inversely proportional to the length of time it samples, so for lower-frequency signals on the typical log-spaced spectrogram (i.e. linearly-spaced note values) the resulting DFT looks "noisy" on the low-frequency side because of quantizing effects from the small bin size, so I'm hoping to find a VSTi with the plots baked into the code at a low level, that can take advantage of information not available in the raw output signal.

I'm looking for a synth that is already programmed (Flowstone, Synthedit, and others are beautiful, but I'm not interested in spending the time to learn another language to make a 3 minute demo if there are already-available synths waiting to be used) that has, on a single screen (no menu tabbing) something that shows a scope-like time-domain output and a spectograph of either the applied filter or the output, that varies dynamically (not a single-snapshot of the filter if it is time-modulated).

The idea to buy a modular kit and just attach a hardware scope and spectrum analyzer is interesting, but I'm looking for something fast to setup and take down; there's not much time between classes. For the same reason, a single-VSTi scope with the plots baked into its GUI is ideal; something that I can run in a stripped down, simplified host (or ideally, is stand-alone) so I can arrive in class, wirelessly connect to the audio and video lines, and quickly start the demo.

Serum looks like a possibility - is its filter plot static, or does it change in realtime (e.g. if it's cutoff and resonance are modulated by a LFO)?