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I recently defeated the internal woofer crossover in my Aerius i's and drove it with its own amplifier with an active electronic crossover. This modification totally brought these speakers to a whole new level. This is how the bass is handled in the newer Martin Logan models. Below I will show everyone how it's done and what equipment you need.
To do this you will require an amplifier with internal DSP crossover capabilities. The easiest way to do this is with modern Class D professional audio amps, I'm my case I've picked a Crown XLS Drivecore 1002, these are very good sounding Hypex amps. I bought this nearly new for $275.
We will need to open up the back the speaker to get at the the woofer and binding posts. The back panel can be very stuck and can be tricky to get off. I found by hammering a razor blade into the gap between the door and cabinet broke the seal without damaging anything.
After you get the panel off you will need to run a set of wires straight from the lower set of binding posts to the woofer. In my case I decided to add another set of binding posts for this purpose. CHECK YOUR POLARITY, in my case the woofer in the Aerius i are wired out of phase inside the cabinet, this is verified by crossover schematics.
Here you can see the new posts. If you can't solder you could probably get some of those little copper spades and just clamp them under the binding post nuts.
After you get everything back together get your new amp hooked up, you will need to use a Pre-out on your pre-amp or receiver to feed a full range signal.
Turn the gains all the way down and turn everything on, setup your crossover slopes the same as factory to start. In my case I have a bandpass crossover setup at 450 Hz and 80hz, I'm running a subwoofer the the bandpass feature is awesome.
After you get everything setup the way you like play some music and setup the gains to a comfortable level, go listen and repeat until you get them where you like. This took my less than 1 track to get them set so don't overthink it.
Closing thoughts: You can do this with DSP plate amps, or you can buy pro audio processors and output to other amplifiers. But both of these options are many times more expensive than this and more complicated. There are several other models of pro audio amps that have more extensive DSP capabilities, but again, more expensive. With an active crossover and gain control it would be easy to try different woofers and be able to blend them easily.
To do this you will require an amplifier with internal DSP crossover capabilities. The easiest way to do this is with modern Class D professional audio amps, I'm my case I've picked a Crown XLS Drivecore 1002, these are very good sounding Hypex amps. I bought this nearly new for $275.
We will need to open up the back the speaker to get at the the woofer and binding posts. The back panel can be very stuck and can be tricky to get off. I found by hammering a razor blade into the gap between the door and cabinet broke the seal without damaging anything.

After you get the panel off you will need to run a set of wires straight from the lower set of binding posts to the woofer. In my case I decided to add another set of binding posts for this purpose. CHECK YOUR POLARITY, in my case the woofer in the Aerius i are wired out of phase inside the cabinet, this is verified by crossover schematics.

Here you can see the new posts. If you can't solder you could probably get some of those little copper spades and just clamp them under the binding post nuts.

After you get everything back together get your new amp hooked up, you will need to use a Pre-out on your pre-amp or receiver to feed a full range signal.
Turn the gains all the way down and turn everything on, setup your crossover slopes the same as factory to start. In my case I have a bandpass crossover setup at 450 Hz and 80hz, I'm running a subwoofer the the bandpass feature is awesome.


After you get everything setup the way you like play some music and setup the gains to a comfortable level, go listen and repeat until you get them where you like. This took my less than 1 track to get them set so don't overthink it.
Closing thoughts: You can do this with DSP plate amps, or you can buy pro audio processors and output to other amplifiers. But both of these options are many times more expensive than this and more complicated. There are several other models of pro audio amps that have more extensive DSP capabilities, but again, more expensive. With an active crossover and gain control it would be easy to try different woofers and be able to blend them easily.