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**Bibby** · 18 September 2005, 20:19

The front of the pocket removed. You may need to drill out the plastic plugs from the rear of the card that hold it in place. I found a Stanley knife inserted between the doorcard and the pocket facilitated cutting through the plugs.

This is the area of the card I will be using for my builds. I have whipped up a paper template to make sure I cut the wood to the required shape.

Place it onto the 12mm ply and draw around it.

You do not need to use birch ply, you could use mdf which is a lot cheaper. However, I prefer to birch ply because it’s easier to work with, creates less dust (that won’t kill you like mdf dust) when cutting and is stronger for a given weight than mdf. Apart from that, it’s real wood!

Out with the jigsaw and cut. I need to cut out the inside too as I am venting my speakers into the door. If you are only going to use the build as the enclosure volume for your drivers, you do not need to cut out the centre.

**Bibby** · 18 September 2005, 20:19

This is where it will be mounted to the doorcard. Now I need to make the front baffle.

The mids and the tweeters will be sharing a common baffle. I like to do this as it helps retain a quality sound image without separation. If you mount the mids in the doors (or kick area) and mount the tweeters up high (in the dash or a-pillars) you will notice a separation of the image. You will be able to hear the tweeters source up high and the mids source low down. You can eliminate it to some extent via eq and crossover settings but you will always get a better image with the source drivers all close together.

They also need to be angled upward and rearward slightly. The aim is to have the soundstage up at eye level, not down by your knees. Only through spending time aiming your drivers will you find the sweet spot. Again, eq, time alignment and crossover settings can help but it’s is easier to set up the audio if you get the driver positioning as spot on as you can during the install.

Remember that any car audio equipment can be made to sound “good”. It’s all in the install. You do not need expensive equipment to get a good sound in the car. The most expensive audio equipment installed poorly is money wasted. Budget kit installed properly is the way ahead. Your ears will thank you for it.

Measure up.

The Morel USA drivers I use have a large diameter but are reasonably shallow. Because of the depth of the grille, I am forced to use 1” thick birch ply. It’s the only way I can countersink them in without using two layers of wood. You may not need to use such a thick wood.

**Bibby** · 18 September 2005, 20:20

Time for the router to play.

I need two levels on the wood. The front of the baffle will mount the lip of the grille ring but I still need an internal lip to mount the drivers. Whether or not you can get away with just one hole will be determined by your drivers.

If you do not have a router but still need the inner lip you can simply use two layers of wood glued together. Use a jigsaw to cut the larger aperture in the top layer, and a smaller hole in the bottom layer. Sandwich them together with good wood glue and you get the same result.

That’s one done.

Make sure the grille ring fits.

Both holes cut, onto the next step.

**Bibby** · 18 September 2005, 20:21

I now want to cut the mountings for the tweeters. As I explained earlier I want the mids and tweets on a common baffle.

Here I have marked where they will be.

Unfortunately the hole is too small to use my router or jigsaw, so I used a drill to remove the wood, tidying up the hole with a rasp. I could have used a hole saw (of the right size) but didn’t have one to hand.

Now we can see how the drivers fit into their baffle.

The baffle now needs to be mounted to the doorcard “ring” I made earlier. This is where the chopsticks come in!

Using chopsticks cut to length, I used them as mountings for the baffle. They’re all glued together with a hot glue gun. These are indispensable bits of kit when it comes to installations of this nature. Easy to apply and very quick to dry.

The baffles are now mounted. You can see that they are angled. The driver aiming was calculated at an earlier stage. How you mount your baffles will be up to you.

**Bibby** · 18 September 2005, 20:21

With the builds at this stage positioned on the doorcard, we can see that the pocket I removed will not fit back in place as there is a chopstick in the way. That’s not a problem as we can just cut a bit of the door pocket away to make it fit.

Like this.

It doesn’t matter about the mutilation of the pocket at this stage.

I now want to fix the pocket to the builds. I just used some bits of wood and glued them together with the glue gun. When I saw some bits of wood, I mean bits of wood cut in sizes that bring the build and the pockets together without moving them from their fixed positions.

Glue the wood in place.

It will all come away as one now, with the pocket and build frame where they should be.

Now we have the frame of the build ready for the fibreglassing stage.

**Bibby** · 18 September 2005, 20:22

The frame needs to be covered in fleece, stretched tightly as this will be helping making the shape of the final build. Staple it to the rear of the frame like so.

It should look like the picture below

If we take it to the doorcard, we can see how it’s coming along.

The resin needs to be applied quite heavily so that the fleece is saturated. The fleece will bond to the frame with the use of the resin. Not only do I brush the resin onto the outside of the fleece but I also brush it onto the fleece inside the frame too. This way I know the fleece is nicely soaked in resin and I will achieve the maximum strength at this stage.

Here it is covered in the resin.

**Bibby** · 18 September 2005, 20:22

Purchase resin and catalyst from a local supplier. Check in the Yellow Pages. I get mine from a roofing supplier who specialises in fibreglass. Do not go to Halfords or a motor factors because you will pay through the nose. You can buy it by the kilo in buckets from a proper supplier for the price you pay for a small tin in Halfords. They will also advise you on how to use it!

Now it is set I can remove the excess material from the rear of the frame. The frame mounts onto the doorcard and I cannot achieve a seal if the surface is not flat. More on that later.

I use a combination of a rasp and Stanley knife to file and cut the material away. It will be hard and sharp. Wear gloves.

Don’t forget the speaker mounting holes.

This is the underside now it is tidied up.

The baffle is not only a mount for your drivers. It is also a barrier between the front and rear waves that it produces. We need to make sure the front of the baffle is sealed from the rear. If it was mounted to the doorcard as it is now you can see that there will be airflow between the front and rear of the baffle, as there is no way you could make an airtight seal in this state.

**Bibby** · 18 September 2005, 20:23

Using resin and fleece we can block up the gap that is evident behind the pocket. Layer the fleece and soak it in resin, we need to lose the air gap.

I have also used filler on the reverse side once the resin has dried, just to be 100% sure that I have left no holes. The door pod doubles up as part of the enclosure here (part, because I also use the inside of the door) but it could be the whole enclosure, depending on your driver. Make sure it is well sealed.

The surfaces of the builds are rough from the fleece/resin combination. You can’t really just sand it down as you would eventually cut through the resin and into the fleece trying to get it flat. We use filler instead.

I use a putty knife to apply the filler. You don’t need to trowel it on as you just want to fill holes as opposed to creating hills. Scrape it onto the surface and it will fill up the pits.

**Bibby** · 18 September 2005, 20:23

There may be areas where you need to be heavier with the filler if you want to create smooth curves where there were angles previously. In the pic above you can see that the left side of the build has a lot of filler as I wanted to have a curve rather than an angle where the pocket protrudes from the build.

Once it has dried, go over it with a rasp to remove the large bits, and then use a coarse abrasive paper to start to smoothen the surface. A P60 works pretty well. I do not use sandpaper but an aluminium oxide paper. It lasts a lot longer and is much stronger than sandpaper.

Sanding takes time and you will need patience…

If it’s still not completely smooth, mark up the bits that still need a bit of filler rather than plastering the whole build. Apply the filler, wait to dry then sand down again. You only need do this stage once if you have done the first stage properly.

**Bibby** · 18 September 2005, 20:24

Now all the imperfections have been removed you have a nice flat surface on the build. Go over it with a fine paper to smoothen it up nicely.

Now I have two builds awaiting finishing.

Final touches to the underside makes sure they fit uniformly onto the doorcard. When the initial “ring” is fixed and sealed to the doorcard, I know that I have a good leak-free enclosure for my drivers as the build is sealed up airtight too.

I recommend adding sound deadening material (such as Dynamat) to the inner skin of your doors if you’re going to mount speakers on the doorcards. It will help tighten up the sound, improving midbass response and eliminating colouration from the door vibrating.

It’s down to personal preference where you go from here. You could have them spray painted or trim them with a fabric of choice. My trimming sucks so I’ll be taking them to an upholsterer before finally fitting them to the doorcards.

Hope this helps.

***Rusty*** · 18 September 2005, 20:36

Nice work. Please post some pictures of the finished results.

**pastures16** · 18 September 2005, 21:01

yep no pics mate

**Alistair C** · 18 September 2005, 21:23

good god they're big drivers! Now you are sure you'll still be able to get your knees in there!!??
Nice work so far - only difference in the way that I work is by using thin cotton (T-shirt) rather than a fleece material. Although the first layer is much thinner and therefore requires more layers to build up (glass fibre & resin from the inside), it means that the surface finish is smoother and needs less finishing with filler. It also means that any rucks in the material are significantly less obtrusive.
Good fun though GRPing!

How is the whole thing attached on to the door? Bet it's going to weigh a few KG!

**Bibby** · 18 September 2005, 21:43

They're not too heavy Al, and they don't really get in the way. I had these installed in my 90 in a similar configuration, and I've already had them in the S2.

I guess if you're not used to them it would be a bit odd.

The build will be screwed to the doorcard from behind with the use of those big penny washers, then it will be screwed into the door itself from inside the build, through the doorcard.

As for being big... well, there's no replacement for displacement! If you want oodles of midbass up front, these Morels are pretty much unbeatable.

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