[rth32]

I have started with base system and have added Vibe Slick 4 centre, front OEM tweeters, MS-8 and Technic harness. Set up is as follows:
Ch1 FL high
Ch2 FR high
Ch3 RL
Ch4 RR
Ch5 Centre
Ch6 FL lo
Ch7 FR lo
Ch8 Unused

Analysed input signal to level signal with starting from base system and set up as:
Subs 0
Front - 2 way - 50Hz/24db 200Hz/24dB
Centre - 1 way - 200Hz/24dB
Sides - 1 way - 200Hz/24dB
Cal @ -21dB
Listen at -6dB

Have also turned HU bass to max and MS-8 sub setting to max.

Very please with results so far. Much better than base system with great sound stage created by MS-8. Still lacking low down punch and after listening to system for lengthy periods, you realise it is still top end heavy. Was thinking of adding a 2 channel amp such as JL XD200/2 for the 2 under seats. I realise these aren't subs and thought it better to keep them as separate channels to give the lows / mids a lift. Really want to keep the OEM speakers for now to get the max performance from them until I can do no more.

Any comments please would be appreciated as to improving current setup or recommendations for next stage.

[ctuna]

The base system only has 6.5 inch speakers under the seats.
I would upgrade those and the front doors at least . You can now get
a Jl800/8 with 8 channels so its enough to amp everything.

[rth32]

Thanks for reply ctuna.

Have had a rethink about what is going on here with the crossovers and what was going on in the base audio system prior to MS-8 install. I think I am restricting the speaker performance with the crossover settings I am using so have now set it up as follows:

Set HU base back to flat along with MS-8 sub setting

Subs 0
Front 2 way, 20Hz/12dB and 120 Hz/12dB
Centre 1 way, 80Hz/24dB
Sides 1 way, 120Hz, 24dB
Cal -20dB
Listen at -6dB

WOW, what a difference. Packs a real punch now with loads of low end and the mid base that seamed to be missing is back. Really rich sound with good sound stage. Will probably keep tinkering but I think these settings are a good starting point for those who've installed MS-8 and are struggling with base response.