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Lesson 9

Subtractive synthesis: the whole chain

Oscillator, filter, two envelopes, an LFO — every module you have met, finally playing as one instrument.

You already know every part in this lesson. What you have not done is hold them as one instrument: an oscillator makes a bright recipe, a filter carves it, one envelope shapes loudness, another shapes brightness, an LFO keeps something moving underneath. That chain — source → filter → amplifier, with modulators aimed at it — is subtractive synthesis, and it is the floor plan of nearly every synthesizer ever sold.

Why this order

The order is the logic of lessons 2 through 6 played forward: you can only carve harmonics that exist, so the rich wave comes first and the filter second; loudness is the last thing the listener meets, so the amp stage sits at the end. The modulators — envelopes and LFOs — are not in the audio path at all. They stand beside it, hands on the knobs, which is why the same envelope could drive loudness in lesson 3 and cutoff in lesson 5 without the audio routing changing at all.

Presets:
spectrumoutput

A complete little synthesizer. Start from each preset — bass, lead, pad — hold a note, and then find which single control matters most to its character: the bass lives on its filter envelope, the lead on wave + cutoff, the pad on slow attack and the LFO. Then break each preset on purpose and rebuild it.

Sound-design recipes you will meet in the wild are just settings for this one chain: "saw, cutoff low, filter env fast and deep" is an acid bass; "square, slow attack, LFO on cutoff" is a synth-brass pad. You can now read those sentences the way a cook reads a recipe.
On your device

This chain is why every Elektron device's page row looks the way it does: TRIG → source page → FLTR → AMP → LFO/MOD is the rack, left to right. The machines below are each device's take on the source slot — everything after them you have already bridged in lessons 4–6: