Z4 Audio Install

[Richard!]

My brother and I are upgrading the sound in my Z4. The aim is to improve the sound quality while keep everything looking stock.

Phase one was completed today, getting the subs installed and temporary mount the sub amp. Words by my brother Patrick:

_______________________________________________
Objective: Improve SQ while retaining stock look

Headunit: Stock

Components: Unknown right now, but maybe Genesis A16
Front Amp: Genesis Profile 4 bridged

Subs: 2 Genesis 6x9 subs 4ohm
Sub Amp: Genesis Profile Sub

Processing:
AudioControl LC6i (line level converter)
Audio System PM/4 (5 chan analogue parametric EQ + sub level / 1 chan eq)

The stock system seems to be typically boomy at the bottom end and mid / top end sounds like it has a blanket over it.

Part 1: The bottom end:

The subs from Genesis:

Installation of the Genesis 6x9 subs and setup one temporary install of an amp and the LC6i

Step 1: Pull the two storage trays out from behind the seats, measure up and cut some baffles out of 18mm birch ply

Step 2: Repeat on side B:

Step 3: Eye up the speaker fit:

Step 4: Make a baffle for the other side, you can see here some trailing to fit Image Dynamics ID8's but they would have stuck out pretty far and the mounting bolts would have gotten in the way. A shallower 8 might have worked:

Step 5: Test fit sub after cutting a hole and routing a lip for it to sit into - this lets the speaker sit as far in a possible to allow more room for covers:

Step 6: Sound deaden the metal and close up any obvious holes the cabin. Add 4 bolts with nuts to hold them in.

Step 7: Spray paint the ply black so there's nothing too light to shine out from behind the seat. Strip some speaker cable and add push fit connectors:

Step 8: Slap a speaker in for a test fit:

Step 9: Repeat on side B:

Step 10: Take the plastic trays and chop down until they clear the speakers with a good amount of gap - speaker cloth will go over the hole:

Step 11: Cut and shut a quick power system together with the Genesis Profile sub and LC6i. The source signal is taken from the rear speakers - the wires are right behind the carpet of the bulkhead so it's easy to get at. The LC6 auto turns on when it senses a signal and has a remote out to power on the profile sub:

Step 12: Find a good location for a fuse (40A will do for now):

Step 13: Connect the earth:

Step 14: Positive connected:

Step 15: Drop the carpet on top and you'd never know anything happened underneath (now go for a cup-o-tea)

 

[sk93]

That looks like a pretty good fit there!
Have you got some pics with the speaker cloth in place?

Also, are they the Genesis P69 subs?
I've seen them around, but wasn't so sure a sub would work that well without having a pre-defined enclosure spacing....
Are they good?

 

[Richard!]

Not got the speaker grill cloth in yet Will post pictures once I get it done. It should blend in quite well, with the seats all the way back they are almost completely hidden anyway.

The Genesis 6x9 subs can run IB (infinite baffle). The important thing with IB is to seal the front from the rear as much as possible. The sub's vent into the boot & I've block up many of the holes that lead into the cabin from inside the storage area's. Would need a larger space to make a sealed box for those subs.

They sound good so far, they add a nice bit of fill for the low end. At the moment the front's are still playing full frequency so are competing a little with the subs. Once the front speakers are amped and a crossover set it should sound good. I am planning to use the stock speakers... see how they sound once running of the amp. Hopefully that will get rid of the 'boomyness'.

 

[sk93]

Can you get away with just adding a pair of passive xovers for the fronts?
I've not got the enhanced speakers in my Z, so am looking for a relatively cheep way to obtain good sound.
I also don't want to loose any storage space to amps / coils / fuseboxes etc that normally take up the space

 

[Richard!]

The speakers are already crossed, I just need to tap into the speaker cables going to the doors. I can set the cross over point for the subs/speakers on the amps.

I also don't want to loose any space, the Genesis amps are quite slim so they should go into the back of the boot above the battery leaving a level floor. The other option I am considering is to vertically mount them against the front of the boot and put a cover over the front to hide them. I'm currently leaning towards the first option.

(note: Don't use a coil it doesn't help)

 

[Andy]

sweet. kinda similar to mine altho im using a cleansweep & Alpine PDX4.150, & focals, but same idea.

there's a nice mounting point for an amp on the back carpet where the dsp amp would be, mine even had a strap which fit the alpine perfectly.

might i suggest you get the covers for the oem subs, they dont cost much and will look a lot better than the cubbys + carpet you're trying to achieve, just snap right in.

 

[sk93]

might i suggest you get the covers for the oem subs, they dont cost much and will look a lot better than the cubbys + carpet you're trying to achieve, just snap right in.

PN: 51437055053 & 51167055054?

At $120 for both, it's not a bad deal..

 

[Richard!]

Thanks for the part number on those covers.

I got a spare set of storage bins on ebay for £20 so its no huge loss. Advantage of doing it this way there is less material coving the speaker.

I'm gonna see how the covers look once they are finished and decide if I should get the BMW covers.

 

[SirSimon]

Looks very impressive mate!

 

[Richard!]

thanks

Speaker grill cloth now fitted.

 

[Andy]

does look good !

i have two spare cubby boxes if anyone wants them for this purpose ?

 

[Anonymous]

Very nice install, was wondering about cutting down the stock cubbies to do this rather than buying the proper grills, think thats a great cash happy alternative!

 

[TH3R4POR]

I really like the angle of the last photo

 

[Richard!]

Cutting the boxes provides a larger area for the sound to get out, no good hiding it behind plastic. (at least that's the way it looks based on the diagram of the parts)


The last photo was taken at 10mm with a Canon 10-22mm wide angle lens. Its great for interior shots, I really like that lens.

 

[rob davey]

Is there not an output from the head unit for the amp? I wouldn't have thought the standard bmw setup with an amp just splices into a rear speaker signal so it must be possible :scratchhead:

 

[un1eash]

The standard BMW system that uses an amp has a digital signal from the headunit to amp which cannot be replicated or used with aftermarket amps.

 

[Andy]

Meaning the Original OE Upgraded units, the 2 optional extra systems, 10 speakers and 10 speakers with DSP / Carver / Logic7 - all use digital.

The basic (standard) 6 speaker system is the one which you need to tap into the speakers.

You *could* do exactly the same as this with the other two systems, to get pre-outs but you'd be effectively double-amping the system and the rears wouldn't be full frequency.

 

[Richard!]

When I get round to continuing with this install I am going to be adding speaker cable to the front to run the front speakers of a separate amp. As part of that I will also be adding cable to run the line level converter from the front signal. I have heard that BMW stereo messes with the single for the rear (don't know if that is true).

I am hoping that this will improve the sound quality. Just setting the crossover on the front speakers will stop them from attempting to play low frequencies. That should really help a lot, plus they will have a decent bit of head room when it come to amp power.

If I still not happy I can look to upgrade the front speaker with some Dynaudio's, I have these in another car and love em But thats very much on the back burner...

 

[kartman]

where do you keep the subs in Z4?

 

[sk93]

where do you keep the subs in Z4?

see the very first post

(behind the seats)