Speakers amps and OHM's- I'm easily confused

The replacement (not bought yet) will fit where the oe one is currently and I'm going to do wiring as required. Can't use the oe connection at the amp as its specific to the factory unit, just some wires to cut and some to add for the shelf speakers.
It can handle different impedance on separate channels according to the supplier. Series works as it will be easier to wire and gives 2ohm impedance which the amp can handle.

I am basing all of this on reading guidance elsewhere as it appears that as long as I don't try to run a rave from the car, volume wise, the amp will handle it.

Please excuse any egg-sucking lessons which may follow

It would be easier to check if you had a link to the actual amp, but in theory what you propose in terms of speaker arrangement sounds suitable. I'm not sure how the dash + door & shelf split will actually sound, but worst-case you might have to swap it to dash & door + shelf instead.

I would suggest checking a couple of things on the power side:

1. Wire gauge: If the replacement amp is more powerful than the OE one, it may well require larger power cables. Don't skimp on this, as even if you try to keep the volume low an amp can use a surprising amount of current.

2. Fuse rating: Make sure that the new amp is fused correctly, as per the manufacturer's instructions. Note that this is not an alternative to having proper-sized cables!

Hope this helps!

Sorry, I'm a bit late to this party.

Your plan is perfectly reasonable. If you do run into trouble it'll be if you turn it up too much. It's current that will annoy your amp. Less ohms = more current. But also more volume = more current.
Of course you'll not be able to do anything to balance the shelf and door speakers as they are wired together.

Anyway, my other though is this... It's likely that the speakers in the dash and on the shelf are smaller and handle the mid and top. The ones in the doors are likely to be handling the low frequencies. The stock amp will likely be doing the frequency split - it'll have a crossover in it.
If that's true (and it's a total guess on my part) your new set up will put the full range into all the speakers which they may not be able to cope with. The door speakers won't care much but the smaller ones in the dash and on the shelf might.

My old MR2 has a power amp and EQ under the seat so I can tweak it so I like it. But the standard dash speakers are only 4 inch and if I try and put any bass in they just hit their end stops and make a farty noise. My plan is to do a more modern like set up and put some slightly bigger drivers in the doors and build a crossover to take the bass out of the dash speakers (and the HF out of the doors).

James

Yeah... Those bass drivers might have been considered 'full range' in the 80's but they are definitely mids in a luxury car around the 2000's. The bass will be coming from the door speakers. (I really hope the bass was coming from the door speakers...)

Of course I could be completely wrong and it would explain why duggers thinks his radio sounds plop.



Edit. I didn't write 'plop'. I wrote a word starting with 'c' and ending 'rap'. I don't know why 'plop' would be preferable but I quite like it as a word and reserve the right to steal it as my own and use it liberally in future posts.

Plop.

Yeah. I like it... It has a pleasant er, 'ploppy' sound.