I'm giving it four stars only because it's been exactly 6 years since it was updated, and it desperately needs quality of life and bug fixes. Otherwise I'd give it a 5.
At first glance, Charlatan presents as a very simple and limited virtual analog synth, but what sets it apart is its quality analog oscillators and filter. It's oscillators and filters sound excellent and lively, made better by the subtle (almost unnoticeable) analog 'drift' effect employed under the hood, which is uncommon in free plugins. Also, it's kind to your CPU meter, so don't be afraid to use more than one instance.
In essence, Charlatan is somewhat comparable to Roland's Juno-60 or Korg Polysix in terms of capabilities and philosophy. But it actually has more features, such as a proper second oscillator, oscillator sync and ringmod. It could also be considered a stripped down Jupiter-8 or Prophet-5, but in general, it's its own take on the 80s poly synth.
Because of its limitations and wanting to keep things simple, you likely will not stray too far from typical 80s sounds like basses, pads and poly sounds. It's just not as versatile as your typical semi-modular hybrid soft synth. Though I'm sure it can be useful for House, Techno, and other surprising areas. Charlatan is particularly great for basses; some of the best 80s style basses I've heard in a free plugin! It holds up even for synth brass and stabs. It can do string machines, transistor organs, and all sorts of other keyboard sounds as well. With its noise oscillator, it makes surprisingly useful filler FX. Some have even managed to squeeze out dissonant drones and usable drum sounds.
So in essence, it's dead simple and limited, but that's not a bad thing. Limitations breed creativity as they say. It sounds good enough to easily fill the 80s polysynth role, but is versatile enough that you can still find new and interesting timbres by experimenting. Also, don't neglect on the Unison and Stereo modes. Older versions of Charlatan did not have this, but they can really add a lot to the sound.
That said, it's not perfect. Osc 2 can only be detuned up to 6 semitones, which means... no 7th chords. Does the creator have a vendetta against 7th chords, to stop at exactly 6?! There are also bugs. Sometimes I found patches don't load properly, glitches out, or don't sound right, particularly if in POLY mode. And it doesn't seem to honor initial pitch bend messages for fine tuning, though this may not be exclusive to Charlatan. An additional way to alter the drift amount would also have been huge in a free plugin. But these are not deal breakers.
Using it with a chorus is a necessity: The free TAL Chorus LX is a great load-once-and-forget chorus, but any decent BBD or multi-voice chorus will do, but that's a whole other topic. Also you'll want a good reverb. TAL's free reverb plugins are well-suited for the job (I personally like the older TAL-Reverb-2 for its tone) Then there's also Supermassive (free), which can be warm and spacey.
Im having trouble loading preset banks... I wanna use Charlatan in a DAW called Stagelight, but there is no button in the host to open complimentary files, like these preset files.
In Ableton it was easy to do because it offers a button to open preset files, but still, the presets won't show up in Stagelight. Is there another way to add presets?? I just don't see how within the GUI in Charlatan?
this is an incredible instrument that has replaced (the previous king of freeware synths) for me. Charlatan is so ergonomic, easy to navigate, almost too simple, and it is almost impossible to make it sound bad. It is refreshing that it is not yet another clone of some other synth, and that it is a sincere attempt to deliver the goods without getting ahead of itself in terms of usability and expected behavior.