Looking to add some oomph - BMW X6 E71

[Fas1975]

Had my car a few weeks now, unfortunately, whilst the option list was ticked in a lot of places, the audio one was lamentably not done and it's got the standard speaker set up with the professional nav.

I see it has the tweeter / door speaker setup in the front, it has I believe single speaker in each rear door, it looks to have some kind of centre speaker in the middle of the dash and allegedly subs under the front seat, but I've not had a look.

I like my bass a little heavy and when I'm listening to music, there's clipping / cut-out at the louder volumes and a lack of bass that I desire. In my previous car I had a full custom Alpine / JL Audio setup including 2x 8w7's firing into the cabin and they hit hard.

I don't want to go down that route again but I do want extra oomph, so two questions.

1. Any recommendations adding some good bass into an X6. Looking for stealth / minimal intrusion and not a full on custom show build

2. Any recommendations on who to carry out the work? I'm based just outside Slough, Berkshire. I know of Car Audio Security. Any good or any other local recommendations?

Thanks in advance.

[Fas1975]

Cheers guys, will check out the links