I'm looking through some of my old posts, computer files, notes, etc. to see if I can answer your questions. Yeah, it's been a minute hasn't it!?

Quote Originally Posted by Earl K View Post
Mike, nice to see you kicking around these old haunts again.
Hi Earl and thanks - sorry for the lag in replying here - the holiday rush has had me strapped for time.

Quote Originally Posted by Earl K View Post
A good decade back you displayed a pic of the response of your 604E using the N1500a as the crossover. Was that with your GPA refurbished 604E's?
The graph I posted was not from a FR test, it was the sim output from a model that I had done with PCD. In that model, I had imported the FR curves and impedance data, so I presume that data was from the drivers with the refurb'd VCs. Glad to publish those data if you want to see it! Looking at the sim in excel, it appears that a parallel two-way config was used. Driver offsets were zero. The woofer design in the sim is 2nd order L/R crossing at 1.5 kHz 70 dB. There is a series RC (Zobel) with C=13 uF and R=10 Ohm, followed by the lowpass 2nd order section with L2=1.5 mH and C2=8 uF. For the HF section, it was 2nd order parallel with C9=6.0 uF and L9=1.0 mH, with a 0.3 Ohm DCR. There is a 3.0 Ohm series resistor after the HP section AND there is an 8.0 Ohm resistor in parallel leg 1. It will take me a bit to draw this out in a schematic, as I'm sure this description is confusing