Early Urei's???

[Robh3606]

Check out this auction. Take a look at the components?? I though all the Urei's had the "phase coherent" crossovers?? Also look at the frames on the Altec drivers. Also the cabinets?? Is this the right vintage?? I thought they were branded as Urei. So what do we have here???

Rob:)

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=23786&item=5703869330&rd=1

[Don McRitchie]

Definitely not an early UREI. Development work on the first UREI monitors began in 1976 using the 604-8G. The 604E was discontinued in 1973. Not to mention that the cabinet and crossovers for the system in this auction are stock Altec parts. I would guess that someone just replaced the original multicell horn on a stock Altec 612 speaker system with some spare UREI horns at a later date. In fact, after re-reading the auction, I don't think that the seller is claiming anything different.

[Robh3606]

Thanks that kinda what I thought. Wasn't sure. Didn't know you could swap horns on the 604's like that.

Rob:)

[Earl K]

Rob,

- Did you save any pictures from the above mentioned ( ancient ) eBay sale ?

- The reason ?

- "db Magazine" , ( Mar. 1979 ) makes mention of an earlier/prototyping 813 system that predates the 1976 collaboration between Bill Putnam & Ed Long. The earlier systems ( several pairs were built ) seem to have been based on the 604-E ( the 604-E is mentioned a couple of times within the article ) and wasn't time-aligned.

- The mid-1976 collaboration that produced the well known Time-Aligned™ 813 (which used the 604-8G ) appears to have happened after Bill Putnam was already tinkering with his first 813(s) . Ed Longs' addition to the design team produced the 813 as we know it, along with its' 838 network .

- They also produced a second network to retrofit into the earlier 604-E based 813(s) ( the article is a bit ambiguous on whether this retrofit network was Time-Aligned™ ) . The earlier 604-E based system may have been designated the 824 / though that may have been a designation for the retrofit network .

This article is written by Dean Austin, who at the time, was employed by UREI .

:)

[Robh3606]

Hello Earl

Damn I didn't keep them. They sound like exactly what you are describing as well. The were a 604E with one of the original horns.

Rob:)

[Earl K]

Hi Rob

- Thanks for your reply .

- I came across this old thread when searching ( in vane ) for some missing inductor values, ( as given in the 811C & 813C networks ). Since you built up one of these networks for your 811C center fill, do you remember the value for the unlabelled L2 coil ?
- Also, were L1 & L3 center-tapped ?

Thanks <> :)

[Robh3606]

Hello Earl

I have to look when I get home. L1 is a double tapped 2mh inductor . I wound mine from the L1 drawing I got from JBL. Mine came up a little short at 1.8 wound on a 3/4 core. I would use a 1" core diameter if you try to wind one. L3 I couldn't get a drawing for and just did 2 series inductors. Not the best approach but I couldn't see what else to do at the time.

Turns are 176/84/81 18Gage Wire.

Rob:)