Harmony House was on York Avenue, around 62nd street, and yes they did repairs too. I was a grad student in that area 1974-1979, and happened to wander in there, was hooked. They had great stuff, and would have designers/manufacturers in. Joe Grado was there once showing his new Signature cartridge, I think it was $200, and shocking at that high price. Someone asked him about its being fragile so he took the head shell off the arm and threw it across the room to dispel that rumor. They have Harold Beveridge in to show his speakers, so very many. I bought my first high end stuff there, they had Rapport, many many high end items, a truly wonderful store.
Who remembers the Dahlquist DQ-10's?
My first pair of "high-end" speakers. Power hungry critters but what I would give for an updated pair. I powered these with a Peavey CS-400 and a Maccomack Deluxe Line drive passive preamp!! Those were the days! Young and dumb I suppose?