The DCX2496 is both a very powerful EQ and incredibly powerful xover.
You can use a standard RCA to XLR adapter to connect to the DCX.
To connect from the DCX to a standard RCA input amp, you need to use also an inline passive attenuator adapter. The output voltage from the DCX is too high for many consumer amplifier inputs, causing possible audible noise/hiss, as the output signal would be pre-amplified by too much, causing the noisefloor to become audible which would not normally be audible. Parts Express sells these
inline attenuators. You would use from the DCX, a female XLR to female RCA adapter. Use a standard RCA patch cable and connect it to the Harrison Lab attenuator. Then connect the Harrison Lab attenuator into the amplifier input. If you ended up with a hum or buzz from the input or output from the DCX, this would be a ground loop. This is not common, but it will occur sometimes, depending on the specific hardware combination you have. You would use an
ART DTI box to fix this problem. It is a transformer coupled isolation box. It is passive. If you use the DTI on the output from the DCX, you don't need the XLR to RCA adapter. Just use a standard XLR patch cable from the DCX output to DTI input. Then use a RCA patch cable from the DTI output to the Harrison Lab attenuator.
No matter what adapter or conversion box you use, this will still be far under your $500 stated budget, and you will have an absolutely transparent and extermely powerful DSP E.Q./Crossover device. For easiest adjustment, you can link the DCX to your PC Laptop using a serial cable. You will need a
USB to Serial adapter with most modern laptops. But these adapters are not expensive. You would also need a
serial extension cable, as the adapter cable is only a few inches long.
-Chris