All advantages/disadvantages of pods are discussed in other sections
of the website. This page describes building techniques.
Step 1: Car Preparation
Protect upholstery, carpet and panels by lining up with plastic and
masking tape. If any resin gets to a seat or carpet, there is no way to get it
out. Take the extra time to make sure any potential spill won't cause damages to
your car. Make sure you will not interfere with clutch, hood release or other
mechanical parts.
Step 2: Making a Mold (Back Piece)
If you are mounting the pod to a flat surface, such as a door panel,
then all you have to do is to make a template out of cardboard. Use the template to
transfer the contour of the area to a piece of particleboard or MDF. This is the
back of your pod.
If you are not lucky enough to have a flat surface to work with, you
need to make a fiberglass back piece. For example, let's say you are building the
pods to go in the corners of the floor, between the firewall and kick panels:
- Line the area to be molded with aluminum foil. This way, the
mat won't stick to your car or liner.
- Cut a piece of fiberglass mat/cloth. It should be at least a
couple inches bigger than the final pod size.
- You can either apply the resin to the mat with a paint brush, or dip
the mat in the resin.
- Place the wet mat on the surface, let dry to hold shape.
- If the mat won't stay, or sticks to your gloves, use a paint
brush. Sometimes masking or duct tape will help keeping the mat in position for
curing. Fine metal mesh or chicken wire could help hold the fiberglass in place for
curing when building complicated shapes.
- Let the piece cure. If once the piece has cured it is not hard
enough, you might need to add one or two more layers of fiberglass. You can do this
on a workbench. Remember, you are only trying to get the shape here, the back piece
does not have to be rock-solid at this point.
You now have the back piece of your pod. Other options is to
cover a factory panel with cloth, add resin to the cloth for hardening, and use the
factory panel as part of your kick panel.
Step 3: Baffle (Front Piece) Fabrication
The best material to work with is MDF. If the enclosure is for
low energy applications (such as mids and tweeters), a couple layers of 1/4" plywood
would work.
With a jig saw, drill and router, you can build the baffle and mold
it to accommodate your speakers. Carefully plan the layout, speaker mounting
configuration and grilles.
Step 4: Speaker Positioning/Aiming
Once you have the baffle, connect wires to the speakers. Mount
the speaker(s) on the baffle. Using metal braces, pieces of wood, etc, connect
baffle and back part together to make a "skeleton". Metal braces are
sometimes better because it is easier to re-aim. At this point, you don't care what
it looks like. If you want, add some cloth to create some kind of a box effect.
Don't worry about the back part of the speakers being semi-exposed.
Start by aiming each pod to the opposite side, at ear height.
From this starting point, play around with different aiming angles for best
results. If you are competing, make sure good results are achieved from both front
seats. If you don't care about passenger's side much, optimize aiming at driver's
side. This is the most important part of the whole process, and may take weeks of
critical listening to get ideal angling. Keep in mind that at this stage you want to
optimize staging and imaging, not sound quality. The speakers will sound a lot
better once the pods are closed off.
Step 5: Joining the Baffle with the Mold
Once speakers are aimed for best sound, remove speakers from baffle.
Trim bottom part to desired size. There are different techniques to shape and
wrap baffle and mold. A lot of people wrap the front and back "skeleton"
with fleece cloth. Resin is applied to the cloth and left to harden. This is
good for concave pods, but for rounded pods you might need to try a different approach:
Fill in areas with a material you can remove later such as paper towels or foil.
Apply first layer of fiberglass. It doesn't have to be perfect, just cover
the intended volume with no major protrusions. Let it harden.
Several layers will need to be added afterwards. How many
depends on how hard you want the enclosure to be, and whether you are using fiberglass mat
or cloth (cloth is thinner).
Step 6: Smoothing the Pods
Once you have a nice strong surface, add auto body filler (i.e.
Bondo®) to round surface off. Let dry and sand. This process will have to be
repeated at least twice, depending on finish desired and what you are using to cover up
the pod. At the beginning, power tools can be used for sanding, but last steps might
require hand sanding.
Step 7: Finishing
After you have a smooth finish, cover up the pod with vinyl, carpet,
etc. Build grilles out out wood and metal mesh, run wires in and seal with silicone
or Liquid Nails (glue), fill enclosure with polyfill if desired and mount speakers.
Make sure you safely secure the pods to your car. Best option
here is to use hidden metal braces, or run screws from the inside of the pod to the car.
Enjoy!
