Using a sub with no sub out on my amp

Well its kinda a know fact the Wharfdales 225 pair well with Rega IO, at least everywhere i read.

Im going the sub route.

Problem is my small budget of $250.  I want a small footprint also, im guessing 10 inch sub is plenty for my size room.  Looking for suggestion on brands and models in my price range, probally not alot of options, i just dont have anymore budget to go higher.

Strange that the amps sound SO different in the same space and same speakers. Is there an impedance mismatch somehow, phase reversal, .... ?

Speakers on your desk. IF you spend a good deal of time in your office, have you considered changing everything in there? I’m retired a few years already, finally weeded unneeded stuff from when I ran my business from here, and accumulated stuff. That opened up possibilities.

Our rooms are similar, mines essentially 11’ x 11’ room, difference is I pulled my desk back away from the front wall (wharfedales ear level inside bookcase opposite), got myself/monitor/keyboard dead center. Whoopee.

Cutting the bookcases down to 3 shelves high and putting a slightly larger top on them made a huge difference.

You can see my office system (or anyone’s system) like this:

Click on their user name. Click on Details. If a system is shown, click on it.

This one should fit the bill!
https://www.parts-express.com/Dayton-Audio-SUB-1000-10-100-Watt-Powered-Subwoofer-300-628
Or this!
Dayton Audio SUB-1200 12" 120 Watt Powered Subwoofer (parts-express.com)

No i have no choice but to put speakers on desktop on small stands, i just have no room.  My setup is in a bedroom, so very very limited ways to setup, desktop seems to be best.  If i pulled the speakers out off the wall and into the room it would open things up im sure, just dont have the space.