Synth1

Free plan MacWindows

What Synth1 is

Synth1 is a software synthesizer plugin for computer music production on Windows and macOS. Its sound engine combines two oscillators and a sub-oscillator with FM, ring modulation, sync, and a modulation envelope. Sound-shaping tools include four filter types, distortion, two LFOs, an arpeggiator, tempo-synchronized delay, and stereo chorus/flanger. The maker lists 32-note polyphony and 128 preset sounds. Synth1 works with DAWs that support VSTi on Windows or AU on Mac; GarageBand and REAPER are named as Mac examples. The Windows VSTi release supports 32- and 64-bit systems from Windows XP through Windows 10 and requires an x86/x64 CPU with SSE2. The 64-bit Mac AU release is for macOS 10.8 and later; Intel Macs were tested, while M1 support is unconfirmed. The Mac version requires a separate download for factory presets. Synth1 is free, and the maker permits commercial music use without contacting them. Its English manual is labeled incomplete, and the plugin is not multitimbral.

Who it suits

Synth1 suits music makers looking for a free instrument plugin for a compatible Windows or Mac DAW. It may also suit commercial music projects, as the maker permits such use without prior contact.

What it does well

Free plugin for Windows and macOS.
Includes two oscillators and a sub-oscillator.
Lists 32-note polyphony and 128 presets.
Commercial music use is permitted.

What to know first

Not multitimbral.
Mac factory presets require a separate download.
M1 support is unconfirmed.
English manual is incomplete.

Plans

Plan	Billed and limits	Price
Freeware	Freeware; VSTi/AU plugin	Free

As daichilab.sakura.ne.jp lists them, read 4 Oct 2026. The maker's own page has the final word.

Getting started

Visit the Synth1 website.
Choose the Windows VSTi or Mac AU release for a compatible system.
Use it in a DAW that supports the corresponding plugin format.
On Mac, download the factory presets separately if you want to use them.
For Mac security or GarageBand sandbox guidance, follow the maker's linked instructions.

Verdict

Synth1 offers a range of synthesis and sound-shaping tools in a free DAW plugin. Check the listed operating-system and processor requirements, and note that Mac presets are a separate download.

Questions

Is Synth1 free?

Yes. The listed Freeware plan costs nothing.

Which platforms and plugin formats does Synth1 support?

It supports Windows with VSTi 2.4 and macOS with AU version 2. The listed Windows release is 32/64-bit; the Mac release is 64-bit.

Which DAWs can run Synth1?

It works with DAWs that support VSTi on Windows or AU on Mac. GarageBand and REAPER are named as Mac examples.

Can I use Synth1 in commercial music?

Yes. The maker says commercial music use is allowed without contacting them.

Does the Mac version include the factory presets?

No. The Mac version does not include them by default, so they must be downloaded separately.

Is Synth1 multitimbral?

No. The English manual says Synth1 is not multitimbral.

Facts from Synth1's own pages

Commercial use: The maker says Synth1 may be used in commercial music without contacting the maker. · daichilab.sakura.ne.jp, 4 Oct 2026
DAW compatibility: It works with DAWs that support VSTi on Windows or AU on Mac; the maker names GarageBand and REAPER as Mac examples. · daichilab.sakura.ne.jp, 4 Oct 2026
Mac support: The listed Mac release is AU 64-bit for macOS 10.8 and later; the maker says Intel Macs were tested and M1 Macs were unconfirmed. · daichilab.sakura.ne.jp, 4 Oct 2026
Manual status: The English manual labels itself incomplete. · daichilab.sakura.ne.jp, 4 Oct 2026
Notable limitation: The English manual says Synth1 is not multitimbral. · daichilab.sakura.ne.jp, 4 Oct 2026
Preset installation: The Mac version does not include the factory presets by default, so they must be downloaded separately. · daichilab.sakura.ne.jp, 4 Oct 2026
Purpose: Synth1 is a software synthesizer intended for computer music production. · daichilab.sakura.ne.jp, 4 Oct 2026
Security note: The maker documents a GarageBand sandbox that changes where the zipbank folder is stored and links to instructions for a macOS security warning. · daichilab.sakura.ne.jp, 4 Oct 2026
Sound shaping: It includes four filter types, distortion, two LFOs, an arpeggiator, tempo-synchronized delay, and stereo chorus/flanger. · daichilab.sakura.ne.jp, 4 Oct 2026
Support: The maker asks users to report bugs by email and says it will respond as much as possible. · daichilab.sakura.ne.jp, 4 Oct 2026
Synthesis: It has two oscillators and a sub-oscillator, with FM, ring modulation, sync, and a modulation envelope. · daichilab.sakura.ne.jp, 4 Oct 2026
Voices and presets: The maker lists 32-note polyphony and 128 preset sounds. · daichilab.sakura.ne.jp, 4 Oct 2026
Windows support: The listed Windows release is VSTi 32/64-bit for Windows XP, Vista, 7, 8, and 10, and requires an x86/x64 CPU supporting SSE2. · daichilab.sakura.ne.jp, 4 Oct 2026

Where Synth1 stands on Freedom251

Software Synthesizers#10 of 38