Car speaker advice please.

Alot of it is down to application, and know-how. Here, the pricier stuff doesn't seem to hit the mark as some of the core things need improvement beforehand to allow them to excel.

Ideally, having a decent amp to run speakers is beneficial. The pricier stuff since I'd say the 00s is less efficient powerwise, as most headunits lack the detail and power required to run them, now just throw sound out.

Most headunits do around a 'clean' 6W RMS, once you get past the MEGA BASS, SICK SOUND & MAX POWER nonesense around them, claiming they can do 4X50W (Peak). Alpine were one of the first to try and get more power from the headunits, but they also stated a dedicated feed was required for the headunit too. My 9887R can do around 10(ish) Watts per channel, with the 9855 and 9835 doing a similar amount, as well as one I've forgotten the number of ; the one I'm thinking of was called a Baby F1.

Speakers since the 00s aren't very efficient, so as to give them better suspension control etc. so a decent amp is required. Less sensitive speakers get around this problem, which is what some JBLs and moreso Alpine Type E's tend to be ; Alpine's are designed to work with a car headunit. This can bring other problems about however, and decent clean power now amp wise is alot cheaper to get than it used to be.

Where speakers are placed and how they are mounted makes a huge difference too. Ideally, you'd have them almost outside of the car as far foward as possible, to reduce Path Length Differences (PLDs), but that is not always practical or possible! You'd also want them near head height, which again, isn't always possible. But it's amazing what can be done with some known-how.

Mouting the speakers so that they don't have an air gap all around them, and that the mounting itself is solid, and not just some card it is put onto makes a difference too. Phasing of the speakers can bring around pleasant effects, but that's for the next section

Processing power really does help, but ideally, the core steps are always best done first. By processing, I mean a processor which can do
-Time Alignment
-Phasing
-Levels
-EQing

4 cars I know of (2 of which I owned) had the same type of speaker (Rainbow Profis). They sounded very different in each car, where some made changes to improve matters. But that's a story for another day.

I can mount speakers well, and seem to think I know which deadening products are worth buying, but the setup is something I've improved on but am still struggling with; not as much as I used to however. Some who know keep these secrets close to their chest ; many after all had won SQ championships for EMMA and IASCA. I'm happy for anyone interested to say how I get a 'result'.