Vintage IS an imprecise term. I am not disagreeing with the comment above that the Hovland MusiCap is the same type of capacitor as a Mundorf film cap, but the Hovland sounds much more like some quite old vintage caps that are vastly superior to the Mundorf in applications where that particular sound is sought. This dealer/builder frequently uses such vintage capacitors and uses only vintage carbon composition resistors because of sonic consideration. Some of his premium builds includes IRC resistors from the 1930's that are not easy to find. Again, based on his customer's comments on the sound, modern parts may be substituted; like Audio Note coper or silver foil caps.
My own amp is a relatively recent build, but, many of its parts date from 1940-1960. The input and output transformers are probably from the early 1940's and some of the signal path resistors are quite old too. Most of the capacitors are also very old paper-in-oil caps. The modern parts are mostly in the power supply--new electrolytic caps, new power transformer, and new choke. The parts choice was dictated by sound.

