Aragon 2002 Pre amp to a Monitor Audio subwoofer

I can't find any reference to such a preamp. Are you sure you got the model right?

I thought the Aragon 2002 is a stereo power amplifier, No?
DO NOT use a 2 male to 1 female Y adaptor on preamp out and run a single RCA to the subwoofer, IT WILL DAMAGE THE PREAMP!

Connecting a preamp and power amp to a subwoofer:
http://www.gammaelectronics.xyz/images/stereo-review_sept_1995_subwoofer_f6.jpg

Or use a pair of RCA ’Y’ adapter on L and R output of the preamp:
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcR3ADmaeKeY2310rkP09Qx1oD5IJWTAXR4YQ80OST1iUAod...
use 2 pair of RCA interconnect cable, one pair to power amp inputs, another pair to subwoofer line inputs.
https://cdn.head-fi.org/a/20171.jpg

Sorry - The power amp is the 2002. The pre-amp is an Aragon 24K. Hope this helps. Thanks for all the help!

I am assuming there are two pre outs,   run one pair to the amp and a pair to the sub.  You really dont want to tie the left and right preouts to each other .  Let the sub's crossover sum to mono.

If the pre has a single pair two "Y" adapters are required for each channel.   Connect left and right to the sub just as you would any other component.