Compatibility between speakers and sub.

My recommendation are the Vandersteen subs. They use an external crossover between the amp and preamp. When the crossover is dialed in, you are basically plug and play.(Unless you get the new Sub 3's which have a graphic equalizer that needs to be set up).

You can buy a number of subs for less, but integration will be more intensive. I have owned the 2w, 2wq, and Sub 3, all performed seamlessly with my speakers.

Bob

I’m not sure I understand. If I have an integrated amp, does that make a difference? Are you talking about the amp and preamp within the sub? Feel free to speak to me as though I am a third grader.

After spending a pile of cash trying various subs, the SVS SB2000 Pro was finally able to fit in with my room and Klipsch Lascalas. I thought I had given up on a sub ever being able to blend in. They have an app that you can use to tailor the frequency appropriately. I'm so glad I didn't quit searching. Punchy, clean, musical, deep and rockin'. Just sayin' Try them out. five stars

Get a high pass crossover and use what ever sun you want. Matching is mostly about the crossover. I mean most speakers have totally different tweeters, mids and woofers…. The crossovers make them play nice. 

Does your integrated amplifier have R/L RCA sockets labeled Out or Output?

ATC offers the C1 which can be connected to their active speakers. ATC's Pro 12 Also connects to their speakers. They suggests using Dolby DARDT for best performance.