Is there a free synthesizer with presets for Windows?

There is: Loop by Zaweba, a free music maker for Windows, has its own built-in synthesizer with 28 presets. Add one with Track > Add synth track, choose a preset and play. Behind the presets is a full two-oscillator synth with a filter, envelopes, an LFO, glide and a vowel formant filter for vocal-like sounds, so you can also make your own patches from scratch.

It is part of the app rather than a separate plug-in, so there's nothing extra to install or load. Here's what it offers and how to use it well.

Starting from the presets

Presets are the fastest way into any synth. Add a synth track, pick from the 28, and play a few notes on your computer keys or the on-screen keyboard. When one is close to what you want, use it as a starting point and change a setting or two rather than building a sound from nothing.

The synth also drives a lot of what you hear in Loop already. The loops that come with the app were played by Loop's own synth, drum machine and the bundled General MIDI SoundFont, so a preset often fits straight in beside them.

What is under the hood

Two oscillators make the raw sound. Each can be sine, saw, square, triangle or noise, and you can detune one against the other for a thicker, slightly moving tone. Sine is pure and soft, saw is bright and buzzy, square is hollow, and noise is useful for breathy or percussive textures.

A filter shapes the tone: low-pass, high-pass or band-pass, with resonance and its own envelope. Low-pass is the one you'll use most; closing it takes the brightness off, and an envelope on it gives that classic sound that opens and closes on each note.

There are two ADSR envelopes, one for the amp and one for the filter. Attack, decay, sustain and release describe how a note starts, settles, holds and fades. A short attack and release make a pluck; slow ones make a pad.

An LFO can wobble the pitch, the filter or the volume, for vibrato, a filter wobble or a tremolo. Pitch drop adds a quick fall at the start of a note, which is great for punchy basses and synth drums. Glide and mono mode let notes slide into each other, the way a lead line on an old synth does.

The vowel formant filter is the unusual one. It shapes the sound like a voice making vowel sounds, which is how you get choir-like and vocal-ish tones from a synth.

Using it in a song

The synth is an instrument track like any other in Studio mode (F3). Draw notes in the piano roll, record from a USB MIDI keyboard or your computer keys, or tap a riff in the riff editor. The chord helper can drop in a progression, bassline or melody that fits the key, and you can play it on whichever synth preset you like.

Then treat it in the mixer. EQ, compressor, reverb, delay, chorus, distortion and filter effects go on any track, and automation lanes can move every effect knob over time.

Tips for good synth sounds

Change one thing at a time and listen. Synths have a lot of settings, and moving several at once makes it hard to learn what each does.

Leave room for the other parts. A huge, bright pad can drown everything else; closing the filter a little often makes it sit better in a mix.

When you export to MIDI

If you export your song as a MIDI file to use elsewhere, Loop maps its synth presets to sensible General MIDI programs, so the parts still play with a fitting sound in other programs, even though the exact synth sound stays in Loop.