I’ve started soundproofing my car, and the stock Meridian 380W has improved so much that I can’t believe how good it actually is. The dynamics, clarity, and bass have massively improved. There is only a little change in soundstage (virtual instrument positioning in the space), but I don’t need that in a car anyway

And I must say, after soundproofing the doors, the Meridian 380W sounds exceptionally good. Without soundproofing, this system is just wasted potential. I haven’t modified any of the actual audio components. At first, I thought about swapping the side speakers for the ones from the Meridian 825W system, but after checking part numbers, I found out they use the same speakers in both systems. The only possible cheap upgrade would be installing a newer revision of the same speaker from a Discovery Sport to see if there's any difference, but it’s still not Kevlar.


Car doors have three layers: an outer metal panel, an inner metal panel, and a plastic/leather door card. Here’s how I tackled them:

Outer metal panel – Covered 80-90% with CLD mats

Inner metal panel – only 10-15% CLD covered, most important is around the speaker and big flat plates of metal but that’s too weak— inner metal panel vibrates with the music. I’ll redo it and cover 80-90% with CLD mats.

Door card – Also covered 80-90% with CLD mats + about 75-85% fiber mat from 3M


I tested a few damping mats and mainly used STP Aero, as they’re reasonably priced and easy available in my country and perform well in Resonix’s internal tests (https://resonixsoundsolutions.com/resource...ting-data/). Interestingly, the cavity between the metal panels remains empty—I didn’t use any CCF (rubber foam)-type sound diffusers or cover the middle panel with CCF. Maybe later. There’s a ton of space in there, and I estimate I could easily fit a 1-inch-thick mat directly on top of STP Aero, but that’s for another time.

For the door card, I used 3M Thinsulate SM600L (44mm = 1 ¾ inches), which is lightweight, waterproof, non-flammable, and designed for automotive use. It feels similar to building insulation but softer—it doesn’t irritate the lungs or skin. Land Rover door cards are thick, so I could fit up to three layers of Thinsulate in some places, but generally, I used two layers. In the door pocket area, I didn’t add anything. Important tip: this material expands over time, so don’t overstuff it. The 3M mat needs to be glued e.g. using 3M 90 spray adhesive. It doesn’t insulate as well without proper adhesion. I first applied it to the side strip of the door card and then moved on to the bottom section.

I also added damping to the trunk floor panel, where the subwoofer is located. This floor panel is made of some lightweight fiber composite, and tapping on it produces a loud, hollow sound—even worse than metal. I used STP Aero, which helped much, but I am not satisfied enough. If I knock on it, it still sounds too hollow, so I recommend to use STP Gold or something even better based on Resonix’s test data.

I know I wrote a lot, but soundproofing car doors isn’t anything new—it’s a well-known concept. However, I never expected the Meridian system to have so much untapped potential. And that’s really the key takeaway from this post!

PS. You might also notice some black spots where the clips are — that’s because I always line all the clip sockets with Tesa cloth tape. The sockets are such poor quality that the clips become loose after just one or a few removals of the plastic panel (like door card). Even replacing the clip with a new one doesn’t help. So I stick some Tesa cloth tape inside the socket, and the clip fits snugly. It’s hard to see exactly what I mean in the photo, though.

PS2. Oh, and just to stay honest — I also started sound-deadening the trunk lid, center tunnel, and center console (made a few rookie mistakes there since I was still learning). It might have helped ever so slightly, or maybe not at all — definitely no noticeable difference in audio sound.

Click image to enlarge

Click image to enlarge

Well done. The doors are a good & easy place to start.

I stuffed my car full of acoustic insulation, mostly foam, really from the point of view of wanting a quieter car. Also in relation to All Terrain tyres, which really do get increasingly noisy as they get older. Putting them on the opposite side helps a bit as the sipes wear.

A key thing I noticed as I was working my way around the car was the quietness of the car got out of balance. So if you stuff the rear full, the front will seem louder. It's harder to stuff the front as full as you have to tick it in here, there & everywhere.

But I am so glad I have done all the acoustic insulation. If I get another car (probably not) it will be the first thing I would do.

There are templates in the link for around the mirrors. Freelander mirrors are noisy from the wind (& folding). Plus templates for other difficult spots in the car.

Acoustic insulation thread:
https://www.freel2.com/forum/topic33026.html
I have stuffed foam in every place I could find filling it completely.

The boot floor is a honeycomb panel. It's frightening some of the things I have loaded on it & it survived. Including 180 x 3.2 kg roof tiles in the car once!

If I was redoing the ceiling, I would add a bit of butyl. Being a bit pedantic, but when we get those seriously large rain drops with crap Sydney weather, it would deaden the roof a bit more. Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18

I joined that thread about soundproofing. As for the effect of my car's sound insulation after doing the front doors according to the above scheme, apart from improving the audio, there is no noticeable benefit so far – the car has actually become subjectively louder

I think that's impossible, and it's just that a different sound has become more noticeable, probably at a frequency that is more irritating to the human ear. I can definitely hear wind noise more clearly now, which is not pleasant, and the road noise is still there but sounds a bit different. It’s possible that it’s coming from the rear doors and rear wheel arches, which haven’t been done yet. The car seems a lot louder. MY2011 TD4 S Manual
MY2014 Si4 HSE Auto
MY2017 C63S Coupe

That's what I noticed, the car felt it got louder. But when I stuffed the front full of foam it brought the sound back into balance.

Don't overdo the rear of the car, as it is much harder to then fill the front of the car to bring the sound back into balance.

Even today years after doing the insulation, I am sort of occasionally listening to the typical city traffic background noise out of interest. The car is pretty quiet. Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18

A thread on subwoofer modifications.
https://www.freel2.com/forum/topic36259.html
My guess is leave the boot floor (not Trunk (in other words not tRump lingo))* alone,... because it is a honeycomb structure, probably FRP (fibre reinforced plastic) so is will be pretty transparent from a subwoofer aspect.

If one is interested in fluffing around with hardware & SOFTWARE, then upgrade to the premium 825 watt setup:
https://www.freel2.com/forum/topic23292.html
This thread is well worth a read even if you are not going to do it.

But getting the car's background noise level down is worth the effort I believe.

Once you start on the acoustic insulation like me, it becomes all encompassing. The biggest waste of time for me was pulling the car apart multiple times.

Just stuff the car full first time, especially the front & the ceiling as they are the most time consuming areas.

*I apologise for double brackets. Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18