Doubtless many have tried this, so apologies if it's old news.

The rear speakers sit on the side shelfs, the undersides being hidden behind

the felt trim. Bass frequencies need room to expand, so unclip the trim

and fold the top 9 inches or so inwards,

you may have to cut the trim on the left to leave the boot light in position.

Tuck the felt trim inwards, securing with gaffa if necessary

so that you can see that the underside of the speakers clearly.

the 'space' now seen by the speakers,

though not by any means airtight with the parcel shelf in place,

is nevertheless effectively much larger and gives the bass more depth.

Try it, and I'd be surprised if you don't hear an improvement.

Does this leave the bottoms of the rear speakers exposed into the whole of the boot? I ask because I will often have my dogs in the boot and don't want to give them any ideas of chewing wires or folded back trim!

Could you take a pic with the hatchback open to and post it maybe, show us how it looks?

Yes it does, so you may need a bit of mesh etc. Will post a pic after work Sunday.

Thanks

This shows the trim folded back, held in place with self adhesive velcro. I did this to prove to myself that it works. My next step for a neater solution will be to put the trim back as it was, then cut a large aperture, covering the aperture from behind with acoustically transparent material of the same colour. Maplins do a parcel shelf felt for just this sort of thing apparently. Will post pic when done.

This may work in the combi too ... I'll have a look and post later

This shows the trim folded back, held in place with self adhesive velcro. I did this to prove to myself that it works.

Thanks for very much for posting the pic

My next step for a neater solution will be to put the trim back as it was' date=' then cut a large aperture, covering the aperture from behind with acoustically transparent material of the same colour. Maplins do a parcel shelf felt for just this sort of thing apparently. Will post pic when done.[/quote']

Sounds like a good idea!

Visited Maplins, they tell me the felt is only available online

http://www.maplin.co.uk/Module.aspx?ModuleNo=17725&&source=14&doy=17m4

Drat, black only.

I am sure you can get grey coloured felt for 'stealth' parcel shelves which should be suitable for this application as well

http://cgi.ebay.co.uk/ACOUSTIC-FABRIC-BLUE-DJ-DISCO-BASS-BOX-KARAOKE_W0QQitemZ9713698590QQcategoryZ69967QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It's blue but maybe contact the seller and ask if they can get grey, as per the picture?

found some online at M99, found some cheaper on Ebay but unsure about quality.