As I wait to build an active crossover for my Theater 4's, I was wondering if it was possible to modify the Eminence/Pi crossover to allow biamping? If so, could someone please describe what would be required? Thanks!

Garland

P.S. What got me thinking along these lines is the great bass I've been getting with the 14W per ch. Heathkit. The highs aren't as good as with the Paramours so I'm thinking they might make a great combo in a bi-amped system! The Heath AA-111 is really a fast amp compared to my Paramours so I'm thinking the Paramours might like to free from having to do the Bass thing!

One nice way to do this is to have quarter-inch jacks that wire directly to each motor, and when they are used, they interrupt the passive circuit.

G.

What you'll do is to separate the inputs of your low-pass and high-pass filters. Right now, they're simply connected together, so you'll disconnect them. Then, connect the output of your bass amp to the input of the passive network's low-pass filter, and connect its output to your woofer. Same with the tweeter circuit, connect the output of the tweeter amp to the high-pass input, and then connect its output to the tweeter.

Someday soon, you'll want to implement this filter ahead of the amps and then just remove the high-current network altogether. I'd still suggest that you do something that allows your speakers to do "dual-duty" because then you can connect the speakers to more varieties of amplifiers. I'll have an implementation for this filter using tube amps very soon, so that might be attractive for you to use.

Garland

With the holidays, I've stopped messing around with anything except filling orders and providing support. But I expect to have analysis of the active crossover finished by the first of the year.

Also, if you don't want such a drastic change try adjusting the capacitor around the feedback loop and you might have a simple low pass filter installed after the first 7199 stage. Some folks prefer the low pass filters and think they are a good idea but they do roll the amp off just above 20khz but in a nice steady slope. Without the filters output is good to over 50khz. I have some resistors on order to make some fine adjustments to the 6H30 circuits and when I do that I can get you exact measurements but this amp can do full out put from 20hz to about 50khz with NO visual distortion and about 1.5% measured distortion at 1000hz. It's a great little chassis.