The term "boutique", when applied to guitar amps should mean that a small company is making a better guitar amp than something that a larger company makes. Supposedly these would be higher in quality, having new designs to make them superior to the mass-produced amps. But this is usually not the case, instead, what people call "boutique" amps now, are just copies or "clones" of these original amps, made using crappy modern components, put together by inexperienced builders, who may have been in business only a short time, and they are classified as "boutique" amp builders. copying the amps made by the company (mostly Marshall & Fender) that supposedly didn't make a good enough amp that we would have needed a boutique copy of this amp in the first place. Boutique apparently now means "cheap copy". This is why Bob balks at the term "Boutique amp" being used to describe his amps.
In Bob's words - he builds custom, ultra-high quality, hand-built, ORIGINAL DESIGN guitar amps.