EDIT: My first thought was that they added the 5532 because of how the balance function affect the signal level.
I know that the 5532 is the quietest OP in the 1620. I have use that a lot before in my own stuff. And always as output buffers. I think it's strange UREI use it here and not for the BOOTH output also.
Normally i would never think about using a TL in the main signal path, i only use it in VU Rectifiers, CUE functions and maybe in headphone amps. If i had designed the 1620 back then i had used 5532 almost everywhere.
I also have some other "reflections" about the design. But i guess i read Walt Jung's "IC Op Amp Cookbook", "Audio IC Op Amp Applications" and other by him to many times 20 years ago ;-) The idea that noise etc could be a good thing in a mixer is new to me, but why not ....
But every component that could be removed from the signal path when not used for anything is good. Well, that 's how i think anyway. I think it's to easy to just add stuff to be safe, like RANE does.
Last edited by Pern : 01-30-2009 at 05:09 PM.