A boutique synth refers to a synthesizer typically produced in small quantities by independent manufacturers, often emphasizing unique designs, high-quality components, and a focus on specific sonic characteristics. These instruments often prioritize hands-on control and can come with a higher price point due to their limited availability and specialized craftsmanship. Boutique synths stand out from mass-produced options by offering innovative features or meticulously recreating classic sounds, catering to musicians seeking distinctive and often hard-to-find sonic palettes.