I hope your smart enough to ignore Glory, that has to be one of the dumbest suggestions ever.
Low Fi, IMO is mainly stuff you get at a large chain store, its cheap easy to purchase and looks like its all you need, and it somewhat is unless you actually really care about performance....like Mcdonalds.
Mid-fi, a bit harder to spot in the stores but some companies that make crap have "Elite", "ES", "Master", "Select" gear that is the top of their respective lines......a bit less afordable but pretty justifiable to many folks. It also is companies that have always produced well recieved and priced gear, maybe "NAD, Rotel, Rega, Music Hall" fall into this section among many others and its usually somewhat mass produced and many have a long track record of value. These might be considered like "Outback Steakhouse".
HiFi, boy this can be a large well established company with huge factory they own, could be another large firm that ships out fome parts from overseas and some is in our back yard, could be one guy that makes just a few extreme priced and performing items a year and many times its drop dead sexy. Its almost always very high priced and some is the sort of stuff that most folks simply shake their head at failing to understand why anyone would pay so much for items they feel fall into the earlier price ranges. This stuff is a reservation required suit and tie joint with valet parking, 5 star media reviews, and a palce most will never see or appreciate. man I am bored!