It's been a while since I've been here, but I need help from some of the brains here.
For many years I've been playing with and building Urei 801B duplex drivers and custom horns. The parts are pretty readily available make make a great sounding system.
People keep asking me for my custom horns for the Altec based duplexes, but I hadn't made any because I didn't have an 604 to work with to make my tooling.
I just came up with a pair of 811A monitors, one of which needs a recone so it was a perfect choice to dissect and reverse engineer my horns with. After after removing the 801A horn, I find the throat is a 7/8" bore.
With the B or C series duplex–neither of which have any Altec parts–the throat at the horn is ~1 1/4".
Cross section illustrations of earlier 604 drivers also show a conical throat flare from the compression driver through the woofer center pole.
Does a Stock 604 8G have a conical throat flare?
Did Urei add a restrictor to the 604 8K throat? if so, was this also a feature in the original 604 8G based Urei 801?
This is a very curious discovery to me.
Any tech insight will be appreciated.
eso
Reply With Quote