BaconPaul Six Sines: major 1.2 update adds CZ-style phase-distortion synthesis and more to the free, open-source FM Synthesizer.
High-quality plugins that easily rival commercial releases are available for free these days. One of these examples is Six Sines from BaconPaul, one of the developers of the open-source Surge XT synth.
SixSines is an open-source, free MPE FM Synthesizer plugin that goes beyond the Yamaha DX-7 or TX81Z. This week, BaconPaul has released update 1.2 that pushes the synth even further.
Update 1.2
Also, in version 1.2, BaconPaul Six Sines remains a 100% free and open-source FM synthesizer. In update 1.2, the developer pushes the engine further, adding new sound design features and improvements.
A major highlight is the upgraded source node section, which now includes three new options for each operator. First, you can now work with Casio CZ-like phase distortion synthesis in the new phase remap setting.
The new resonant sweep allows you to add underlying pitch sweeps with windows. This gives you sounds a bit like a shimmering timbre. A bit more crunchy is the new noise option with pink, white, tilt, and LFSR/Chip-style noise
In addition, operator 1 can set its source to audio sidechain input, and each node now has an absolute Hz offset.
These new node options are a fantastic addition, adding a lot of color to the classic FM sounds. Especially the noise section brings interesting noisy results. Casio CZ phase distortion is also very welcome.
More Powerful And Flexible Modulation
Alongside these, update 1.2 benefits from an upgraded modulation engine. This includes tempo-sync for all envelopes, all nodes with LFOs now have a step sequencer, and curve-style LFOs, and LFOs on amplitude-like nodes get an add, scale, and attenuate mode similar to the envelope
The macros in the SuperMacro section are now per-voice mod sources with their own DAHDSR + LFO + 3-slot mod matrix. Other mod changes are:
- new song-position run mode for LFOs (lock phase to the host timeline instead of note attack)
- envelope rate as a modulation target (exponential, ±8x)
- MPE Timbre (bipolar) as a modulation source
- AShape, RShape, and DShape modulatable in the matrix
The output section now includes new filter saturation and resampling options to tame aliasing under high saturation / low-rate ZOH.
There are also various other DSP changes with many MIDI and MPE improvements and implementation of MTS-ESP-aware MPE pitch bends.
Very welcome are the UI changes and improvements. The entire UI is turned sideways, giving loads more room, with many re-layouts and changes. Further, it includes a new color theme editor, a built-in analyzer, and a per-op VU meter.
A fantastic update for the Six Sines open-source FM Synthesizer. I’m glad that BaconPaul opted for a new UI that improves usability.
The new Six Sines update 1.2 is available now on GitHub as a free download for macOS, Linux, and Windows.
More information here: GitHub
Update from April 8, 2025
In January, BaconPaul released the lovely, free, open-source Six Sines FM Synthesizer. Version 1.1.0 is ready to download from GitHub and adds new features and improvements.
Some of the highlights of this update are a new Six Sines, Seven Outs plugin version with individual operator outputs, new window-style waveforms for AM/RM modeling sounds, unison with control, linear and ZOH resampler options, and more.
BaconBaul also added TZLinear FM and Exponential FM as modulation modes for the mod matrix, in addition to PM and RM; add scaling (abs, unipolar, normal) modes to the RM. These make the FM engine even more capable.
There are also plenty of improvements. For example, the new Sine Sines 1.1.0 update ships with a new light mode skin, GUI rescaling (75-150%), and new patches by Videco and SiL3NC3. You can find the full changelog here with all new features and improvements.
An excellent free update for the Six Sines open-source MPE FM Synthesizer.
Article from January 26, 2025
BaconPaul Six Sines is a new, impressive, free, open-source Yamaha-style TX81Z MPE FM Synthesizer plugin for macOS, Linux, and Windows.
Since Thursday, when Behringer announced the BX-1 at NAMM 2025, FM synthesis returned as a big topic in the Synthesizer community. However, interest in this “too complicated to program” synthesis has been waning for several years, especially with the release of the Korg opsix and others.
The fact that there is now another open-source FM Synthesizer plugin fits perfectly into the topic. Say hi to BaconPaul Six Sines.
BaconPaul Six Sines
BaconPaul, known for its Surge VCV Rack version, has published Six Sines, a new free MPE-compatible 64-voice FM Synthesizer plugin. It’s open-source and runs on all major platforms. It is not yet for iOS with AUv3, but I hope it will be in the pipeline.
Sine Sines is a 6-operator FM Synthesizer plugin with a classic structure. At the top, you have direct access to the operators’ ratios. Click on the operator ratio, and a screen unfolds in the last third. Here, you can choose your waveforms, set their phase, use a DAHDSR envelope, route modulation it, and more.
Although the plugin is called Six Sines, each operator offers more than sine waves. You get sine, squarish, and swish and the original TX waveforms from the Yamaha TX81Z Synthesizer.
Then, below, BaconPaul Six Sines hosts a classic FM operator matrix, and on the right, an operator mixer with individual operator pannings.
The last third of the UI explores the depth of each operator. It includes a DAHDSR envelope, a multi-wave LFO, and a modulation matrix with various sources and destinations, including MPE and random.
Further, it hosts a macro section that offers each operator a macro control. You can also work with up to 5x unison. BaconPaul ships the plugin with plenty of factory presets. As of version 1.0.3, the plugin has no effects. I hope that some more will be added.
It is worth mentioning that the developer is constantly updating the plugin.
First Impression
Six Sines is a great-sounding cross-platform free FM Synthesizer. The built-in presets show nicely what is possible. However, I’m torn about the user interface.
On the one hand, BaconPaul Six Sines is very easy to use. Everything is straightforward and clear. However, I do not like its vertical look. You can’t currently scale. I hope there will be a somewhat broader, fully scalable interface. Nevertheless, it is an absolute download recommendation. Don’t miss it
BaconPaul Six Sines is a free download and runs as a standalone app and a CLAP, AU, and VST3 plugin on macOS (native Apple Silicon + Intel), Linux, and Windows. The Six Sines code is open-source.
More information here: GitHub
Thanks for the excellent write up! Look for a version 1.1 sometime in late Feb early Mar
Great! Would love to see an AUv3 for Ipad 🙂
Buon sera, l’ho aggiornato al ultima versione; e non trovo più i preset. Grazie
Buon sera, I’m not the developer no the support line for it 😉 For all these things please contact the developer.