Quadraphonic was new then, and it was way before people talked about "surround sound." These receivers where not cheap and weighed a ton. Some of the model numbers were: 701 & 801 (1971ish); 304, 404 & 504 (around 1974), and 514 (?). AKer tcdriver has posted this pic of a 404 in past archived AK threads: http://i89.photobucket.com/albums/k206/xtcdriver/Fisher 404/2-404.jpg If you google "fisher 404" not much info comes up--some expired for sale listings on ebay, etc., some links to downloadable service manuals. If there are articles or reviews or comprehensive specifications out there they don't rise to the top or even first several screens. We do have some old threads here that mention them, but the one's I've seen so far only include a few snippets of info per thread. So, what can happen if every AKer who owns, has owned, or knows something about these behemoths puts their heads together? Can we assemble a bit more knowledge? So if you have (or have had) one of these, jump in a tell about it (good and bad), and share what you know, and particularly any links to helpful information you might know of. In my case, I have a 404, like tcdriver 's. Got it a few years ago. Worked great after replacing fuses, then after a while gave me intermittent problems. Right now I can't recall what the last one was. Since I had cleaned all the controls and switches, I figured it had to be more serious. Just took it off the shelf this morning and hooked it up, and the only thing I can find wrong right now is the volume slider is dirty or dodgey. Might put it back in service! It would be good to know more about it than I can find, in any case.