I do miss Toronto, always have a brilliant time whenever I'm there to see relatives, friends and ex work colleagues ! I may well zip over next time I'm there and check your car out and have a drink or 3!
Those 10TW3's are meant to be used in a small sealed enclosure and not 'free air' as you are thinking. I've heard one of these in an Audi R8 and sounded fantastic indeed! I have the JL Audio 8W3 v£ 8 inch sub in a custom made enclosure to fit in the left side of my E39 Touring and it can provide astonishing sub bass that's musical, controlled and tight. If you are really wanting to mount subwoofers where the OEM M Audio ones were, then you'll need to search out subwoofer's that are designed to play in a 'free air' installation. These do exist but there's less choice nowadays since technology allows 8/10/12 inch subwoofers to play fantastically well in really tiny enclosures. You'd also need to spend quite a bit more to strengthen the rear parcel shelf area to provide a more solid baffle to mount the subwoofers to, do some fabrication/cutting and you'll also need to perhaps apply sound deadening to the trunk/boot area to minimise rattles/vibrations as the whole area becomes the 'enclosure'. This all adds up and if you aren't so keen on DIY and have a good reputable local audio installer do it, then it's a significant amount extra in costs. The tried and tested, proven time and time.. and time again method to get fantastic sub bass in a saloon/sedan BMW is to have a small enclosure for a 8/10/12 (or dual) and have the enclosure feed/fire through the ski hatch. This method gives 100% sub bass flow into the cabin where you are and you don't need to put sound deadening material in the trunk area or mess about in the parcel shelf area.
For the front, then ideally you'd junk the oem plastic enclosures behind the door card and put in MDF/Birch Ply baffles that'll provide a much more solid base for the upgraded speakers you buy to play from. Many on the forums will 'automatically' say get 6.5's and like the aspect above, you certainly can but you'd most likely need to do some fabrication, check mounting depths, ensure the cone/surround of the speaker doesn't hit the back of the door card by making a small 'spacer', again, if you need to have a local installer do this, costs begin to add up.I personally run excellent 5.25's in the shape of DLS R5A's which produce fantastic amounts of mid bass response and respond down to 50 Hz. I do have them in custom low profile door builds but if I had wanted to stay with the stock door card look, I think they'd have fitted easily in more solid baffles without having to do all the extra work I'd have had to do if I went with 6.5's.
Alpine have just announced the iLX-W650 shallow depth Android Auto/Apple Carplay head unit for a March 19 release in the USA and according to Crutchfield it has a 5 band EQ and 6 channel Time Alignment. These would cover the DSP aspect you mention. Alpine have a RRP of $500 USD but crutchfield and a couple other US based discount retailers have it showing at just $300!!
Maybe create a specific thread for your audio upgrade plans ?!
Ron 1999 - apologies for the thread hijack !
2003 Ex-Police E39 530 Diesel Touring. Alpine White, 260,000+ Miles & climbing!
19" Hartge Nova 5 - with custom painted 'Flash Chrome' centres & Polished Lips (set of 5)
19" Hartge Nova 5 - Awaiting custom re-finish (set of 4)
19" Hartge Classic - with custom powder coated centres in shadow chrome & diamond cut/no lacquer lips (set of 5)
20" Hartge Classic - Awaiting custom re-finish
19" 3Pc Forged wheels - ID retained until re-built & finished (2 sets)
20" 3Pc Forged wheels -ID retained until re-built & finished
19" Centres - ID retained until rebuilt & finished
Full Custom Audio install - Arc Audio KS Mini ampliifers. DLS 5.25" 2 way front components & 4" 2 way co-axials. JL Audio 8W3-V3 subwoofer in stealth enclosure. Parrot Asteroid Smart head unit, custom door builds for DLS front stage & Earthquake SWS6 flatline subwoofers, custom rear pillar speaker pods. LumiDock iPod dock,
H&R Springs, ExoticsTuning front lip spoiler, Sport F/R bumpers upgrade, Carbon Fibre effect printed Vinyl roof wrap, High gloss black vinyl window trim wrap, Hartge bonnet/hood & tailgate badges, rear rooftip spoiler, matt Black kidney grille, projector foglamps.
Hartge auto gearlever, Hartge Handbrake handle, Hartge door sill strips, E46 M3 CSL Alcantara/Tri-stitch SMG steering wheel, full Black Leather Sport seats,
Custom ECU re-map biased for more Power & Torque in Steptronic mode, EGR delete, K&N induction kit, Stainless steel de-cat, Stainless steel exhaust backbox with twin oval pipes. Manual 5 spd gearbox conversion.
Plenty more modifications to come!