There's a ton of different software synthesizers out there right now. Many are very well known and used by the majority of producers, but others are not so well know and are excellent. In this article, I'll be showing 5 'underground' soft synths that deserve a serious look. All of these instruments are available for both Mac and PC, are 64-bit compatible, and are in common plug-in formats like VST and Audio Unit.
FAW Circle is a sound designer's dream synth. Its semi-modular design allows you to enable or disable various modules like multi-mode filters, LFOs, envelopes, sequencers and distortions. There are no 'cables' in Circle's design like you'd see on other modular instruments'¦ Circle uses colored dots on the various modules that you literally 'drag and drop' to the parameter(s) you want to modulate. It's an extremely 'visual' instrument. For example, you can actually watch the envelopes play out (a small dot moves along them over time). Each of the 4 oscillators can be put into an analog mode that gives you your standard waves like saw, triangle and square, but when in wavetable mode, you have a huge selection of sample-based waves. Each oscillator can actually hold two wavetable shapes that can be morphed/frequency modulated by one another. There's even a separately downloaded application that allows you to create your own wavetable shapes (from your own samples) for use in Circle. Circle excels at nearly any type of sound you can image, and because of its highly visual way of programming, it's also a very fun synth to use.
Diversion by Dmitry Sches is the new synth on the block. Its 4 FM/RM oscillators allow you to choose from many virtual, sample-based, and wavetable types. When using wavetable oscillators, there's an editor that allows you to literally draw in the waveform. When using a sample oscillator, you can adjust the start and end points and even load in your own custom samples. Another cool feature I haven't seen in any synth is a built-in recorder that allows you to play a sound in Diversion, record it, then utilize that recording as a wave in any of the oscillators!? Each oscillator in Diversion has its own separate multi-mode filter too, and/or you can apply a filter globally to all via 2 separate busses. These busses not only contain multi-mode filters, but distortion and 'lo-fi' effects too. When sending a sound through non-linear processes like distortions, aliasing (unwanted digital artifacts) can occur'¦ Diversion has you covered here by sending your sounds through an up to 8X oversampling process keeping the sound crisp and clean (at the expense of CPU power however). There's also loads of modulators like 4 LFOs, 4 Envelopes, and 4 multi-stage envelopes that can be used as sequencers. Like many of the other synths, Diversion allow you to easily right-click/control-click parameters to easily MIDI learn them, but you can also assign modulations this way! For example, if you want to modulate OSC1's filter cutoff with an LFO, you simply right-click and choose the LFO from the 'add modulation' menu. It couldn't be easier, and the connections you make this way are even added to the Mod Matrix automatically. You'd think that a synth with this much functionality couldn't make just a simple solid bass or lead, but you'd be wrong (as I was)! Diversion excels at nearly any type of synthesizer sound you throw at it.
This hybrid synth can generate an extreme variety of sounds. Words simply cannot describe the detail and complexity behind Helix, and I think this is why it may have scared a few people off. If you're a true subtractive synth lover, you might find Helix a bit complex'¦ but diving into this incredible synth is worth the effort if you're looking for new and interesting sounds. Nothing in this synth could ever be described as limited! All the normal synth standards are here like envelopes, LFOs, filters, and more, but they all have options and routings unlike your average synth. For example, you get an analog modeled square wave in the oscillator section, but the real power begins when using wave shaping oscillators. There are over a dozen different wave shaping parameters to manipulate your waves into virtually unlimited shapes. There are 8 envelope generators, 4 LFOs with more than your average wave forms, three filters, three shapers with various clipping/distortion options, 2 built-in step sequencers, and a matrix page for routing nearly anything to anything else. It's actually hard to say what this synth excels at because of its flexibility. It can create great sounding bass and lead sounds, but It especially feels at home with ambient or experimental sounds too. It can be very 'Vangelis' sounding and in my opinion that's an extremely good thing!
Aspect Loomer is a great sounding analog modeled synth with a semi-modular nature. You only have a basic set of oscillators to choose from here, but that's the beauty of this instrument. In addition to the the three oscillators (including the noise osc), you get two great sounding multi-mode filters, 3 envelopes, 3 tempo sync'able LFOs, and a modulation matrix section. The real power begins when you choose from the various modulation sources. Many of Loomer's parameters can easily be modulated by one simple knob that can utilize up to three modulation sources. Aspect is perfect for creating sounds with an analog feel. Fat basses, wobbly unstable leads, and retro sounding pads are its specialty.
kHs One has been available now for a few years. This synth is the simplest of the bunch, but it has a great musical sound and is clear and very easy to program. It has two oscillators with selectable saw, square or noise waves, that can be modulated with both a shape control and with sync. There's also a sub oscillator, two multi-mode filters, two LFOs and several effects. Some of the standout features are a great sounding unison mode with detune and spread, and a 'vox' or vowel mode in the filters. Lead sounds seem to be this synths strong point due to the very excellent unison, but rich sounding basses can can be made too.
All of these great instruments have demo versions to try out. Hope you enjoy these great instruments as much as I do. Thanks for reading!