Timrhu -- My memory is hazy about the A&M building but I believe Arnold & Morgan was a standalone building (Is this correct, Albert?) located near a strip shopping mall in Garland, Texas, a northeastern suburb of Dallas. I do not recall if they carried Pioneer gear or not. Albert could probably fill us in on the audio lines they carried in the mid-to-late 1970s.
Yep, Arnold and Morgan was a stand alone building with several sections in the front for the public, a repair center for instruments and audio gear and a separate facility for pianos. The warehouse was large, equipment from one to three levels, depending on weight.
No order, brands I remember in the stereo department.
Audio Research (preamp)
B&W (speakers)
Infinity (speakers, pre amps)
Braun (later became A/D/S in the USA)
Yamaha (speakers, receivers, separate, tuners and turntables)
Pioneer (speakers, receivers and turntables)
Marantz (receivers and turntables)
Dual (turntable)
B&O (integrated, speakers, turntables and cartridges)
Thorens (turntable and arms)
JA MItchell (turntable and arms)
Audio Technica (phono cartridges)
ADC (phono cartridges)
Shure (microphones, phono cartridges)
Ortofon (phono cartridges)
SME (tone arm)
Rabco (tone arm)
Altec (speakers)
JBL (speakers)
Duntech (speakers)
Denon (integrates)
Crown International (amps, preamps, electronic crossovers, open reel)
BGW (amps)
Phase Linear (amps)
DBX (dynamic expanders)
Nakamichi (cassette recorders)
Sony (open reel)
Revox (open reel)
Teac (open reel)
Tascam (open reel)
Mitsubishi (their first projection TV)
Rectilinear Research (speakers)
Maxell, TDK and Scotch tape, cassette and open reel.
Koss (headphones)
Sennheiser (headphones)
Probably missed some, this is all I can clearly recall right now.