20212509: [SOLVED?] : Did some more testing ... The rear speakers are quieter I think because they are not enclosed at all (with the old enclosure?) ,On top of that the input from the satellite radio I hijacked is even lower.. so it's REALLY quite in the back when I use my AUX I made ... I guess I need to enclose the speaker in something to help with the (loudness)

Looking to replace all my 6.5 speakers (4x) in my BASE model Q40 (NO BOSE) with whatever works! Basically Q50

* ( 2 are blown and sound like !@#$ because I guess just old '15 cardboard and /or Lows from Podcast blew them ... constant annoying buzzz on lows when listening to podcast that drives me insane ... )
* there ( I think ) 4Ω max 40W ? ( see photo )
* I'm just looking to replace them with the same type of speaker ( or around same loudness / DB )
* I ordered both of these and they both are too low one was 40RMS but still REALLY QUIET (1/2 -1/3 the loudness) ... https://smile.amazon.com/dp/B00J0DDUDC AND https://smile.amazon.com/gp/product/B07595G6H7
* I swapped one of them with working old speaker and it sounds fine .. almost like the OEM speakers are like 20 amp speakers
* AUDIO, VISUAL & NAVIGATION SYSTEM​​​​​​​ and complete dump of Infiniti Q40

 

I saw you never got a answer on this from a while ago so ill jump in, Rockford fosgate is the best way to go just make sure you replace the tweeters also or else it'll sound odd. if you want high quality sound for cheap get the prime 6.5s anything above prime gets louder and sounds better I believe It goes punch then power, use this info as you please. im not sure if you already changed It out tho

 

Ohh wow that was a LONG time ago ... No it's definly more quite ... if I play the radio it's loud as @#^%# so I assume the feed from the satailite radio was pre amped or something ... it really sucks but then again my ears a shot so it's prb good that it's quiet .. I use a EQ on my phone to bump up the sound a bit before it gets cooked