1. Arturia SEM-V ($99)
Arturia's previous products have often been accused of having a somewhat "samey" sound to them, and while I am not sure that is entirely fair, I can say that they really upped their game with SEM-V, their simulation of the Oberheim SEM synth. To me, this is one of a handful of software synths that has that indefinable "it" that usually defines vintage hardware. It's a synth that sounds alive and organic and is amazingly flexible for how relatively simple the architecture is. Brilliant for basses and leads, and thanks to the "8-Voice Programmer" (a step-sequencer/modulator), arps and steppy sequences and modulated sounds. In addition to the 8-Voice Programmer, there is also a full mod matrix, and very basic Overdrive, Chorus, and Delay effects. If there is one area that lets this synth down, it's the effects - they sound pretty lousy. But switch them off and process through your own choice of effects, and it sounds brilliant. Bit of a CPU hog, but this is a case where it is worth the heavy processor load. (Buy my presets for SEM-V)
2. Camel Audio Alchemy ($249) [Read the Waveformless Review]
Camel Audio's Alchemy is a few years old and probably due for a version 2, but that doesn't mean this super-deep synth isn't still great. With Additive, Spectral, Granular, Sample Playback, and Virtual Analog modes, there is a wide variety of methods to sculpt sounds with right out of the gate. But add to that dozens of filter types, extensive modulation abilities, great performance controls, multiple sequencers, envelopes, LFOs, mult-stage envelopes, and some very nice sounding effects, this is a synth that is easy to get lost in. I do think the sequencer could be made a bit more user-friendly, and some of the factory samples are not that inspiring, but this is a synth with serious abilities if you want to build complex and unusual sounds.
3. D16 Audio Group LuSH-101 ($249) [Read the Waveformless Review]
When this was first released, I got the impression that a lot of people missed the point of this synth. While it does indeed take its inspiration from the venerable Roland SH-101, D16's LuSH-101 uses that as a mere starting point and builds on it from there adding significant new abilities such as polyphony, unison and Supersaw modes, additional envelopes and LFOs, a mod matrix, extensive effects, and the abilities to layer or split up to 8 instances of the synth engine for incredibly thick and intricate sounds. While it certainly does a great job of emulating the 101 if you stick to the parameters that were available in the real thing, that really misses the point, as you can go so much further. A nice, modern update to the 101 that even in its more "modern" settings, still has the sound and spirit of Roland.
4. FXPansion DCAM SynthSquad ($249) [Read the Waveformless Review]
This 2009 collection of synths was one of the first to make me sit up and say "whoa" in the analog-sounding plug-ins world. Consisting of Strobe (a monosynth with a character similar to an SH-101 crossed with a Pro One), Amber (an emulation of divide-down string machines), Cypher (an "Analog FM" type synth), and Fusor (a plug-in that lets you combine multiple layers of Strobe, Cypher, and Amber, process them through effects, and sequence them). Even four years later, these sound fantastic and are a ton of fun to program.
5. GForce Oddity (£99)
Although it was released way back in 2003, GForce's Oddity is still an impressive emulation of the ARP Odyssey. This is mostly a straight-up emulation with no additional features like built-in effects, but it doesn't suffer because of that. Authentic-sounding and very full of analog character, the only thing that really lets this synth down is the absolutely horrible preset management. How about an update with a decent patch management system, Gforce?