In concrete terms:
Low end: (The audio moron) Bose, "all in one racks", wire from Best Buy, any audio equipment from Best Buy, Any audio equipment from Walmart, Any audio Equipment found in a Goodwill store.
For example: Bose 5.1 speakers, $300. receiver, Monster cables from a Best Buy, an Oppo DVD player for all formats.
Mid fi: (The struggling audiophile) anything and everything that costs between $600. per unit, and $2,000. per unit.
Adcom separates, many possible $2K speakers, Kimber PBJ or Hero, a Sony ES CD player, maybe a DA converter Plenty of used stuff, including a used TT.
"Upper" mid fi: (the typical person called an "audiophile")(most of us)$2,000 per item to $6,000. per item.
The great middle class.. tons and tons of stuff, new and used. The folks with HUGE collections of music... The folks who have been into it for years
High end: (the wealthy... and the totally crazy) minimum $6,000. per item up to $100,000. per item.
The MBL crowd... $5K cables... etc.
(sorry I copped out on the equipment samples... but I hope you get my idea...)