Midrange speaker pods: step #2

   The doors at this point are packed with vibroisolation, so it's time to start creating pods.

Creating structure for pods is a creative thing. There are a lot of different solutions and types of construction. You just have to use imagination. It is only important that these pods would be stable, they wouldn't wobble around and they would be joined with the doors, so - construction should be rigid.

I used small wooden bricks as you will see in the pictures below.

    The first problem I encountered is that the door panel/trim is thick so speaker ring (wooden ring on which speaker will be attached) must be quite far from the door structure. Since I didn't had very long screws that would go from wooden speaker ring to the door structure I had to improvise. 

I'll try to sketch what I have done:

    This, of course, is not the best way to create distance between doors and speaker ring, but it did the trick for me. This construction was stable and rigid.
    To create the above construction first of all you have to cut a hole in the door panel where the pod will be. I cut the panel with jigsaw. The hole in panel is needed to measure what will be the distance between door structure and speaker ring. As you can see in the picture below, I have cut hole in the door panel and attached few wooden bricks (not enough).

    After attaching few extra wooden bricks until appropriate distance has been achieved, speaker ring has to be attached.
    The speaker ring should be placed in such angle that speaker would point to the gearbox leaver.

    Next step is to cover this construction with vibroisolation so it would be hermetical (keep in mind that it is impossible to make it airtight - just do your best).

    Then attach the speaker (don't forget to connect the wires... :) ).

   It would be best to apply some silicone between wooden ring and speaker (if the speaker doesn't have rubber ring).

    

In addition I would suggest to put some cloth between doors and door panel. Because panel is made from plastics and the aluminum foil is not very elastic. Since this speaker will produce a lot of vibration, layer of cloth between door and its panel will reduce additional unwanted noises. 

   At this point I haven't created decorative trim for the pods. I'll try to work on them this summer using fiberglass. This will be very difficult task, but interesting and useful.

Midrange speaker pods: step #1

    When I started to upgrade my car audio system, one of the most important part was speakers. Every normal sound system has at least two-component frontal speaker system. By default, midrange speakers are placed in doors (near legs) and tweeters (high frequency speakers) are placed on the front panel or in the upper part of the doors. As you might seen, I have already posted 3 steps on how to create tweeter pods in front pillar trims so that tweeters would be higher than built-in factory tweeters. This time I'll describe how I created midrange speaker pods in my front doors. 

   Audi I own, has original 13cm speakers in doors which were not enough for my system. The most popular speaker size for audio fans is 16.5 cm. These speakers are bigger and able to produce more bass frequency, are louder and more powerful.  

   So the goal is - 16.5cm speakers. As I said that original space allows to setup only 13 cm speakers, so it is necessary to make modifications in the door trim/panel. Before you do this you must understand that this will ruin your original looks of the car interior. But you have to make sacrifices in the name of high quality music in your car.

   The first step is to disassemble the door trim/panel and soundproof the inside of the door. It is very important, because bigger and more powerful speakers produce bigger vibrations. Doors are made of quite thin metal so they tend to resonate creating unnecessary additional sounds. Also from vibrations door metal moves forwards and backwards, so the volume of doors are changing (not much, but still) and it distorts the sound.

I used vibroisolation material that can be bought in specialized car audio stores. Vibroisolation roughly consists of bitumen layer and thin aluminum foil layer. This vibroisolation is quite heavy as its purpose is to make door metal heavier = harder to move.

In the following picture you can see how I isolated my front door from inside:

   This particular isolation material is easy to apply, you just have to peal of the paper which protects the adhesive side and stick it to the metal.

   As you see in the picture above, I have attached plywood form that will support the construction of the speaker pod. This is necessary to have a surface to which I can attach pod construction. 

Preferably metal would be used instead of plywood, because the inside of the doors gets moist in bad weather so wood can rot in these conditions. However, I have these pods installed for about 2 years know and everything is OK. If you use wood, it would be best to apply a coat of protective paint.

   I think everyone knows that speakers can work only in boxes. Well, they CAN work without boxes, but they sound really crappy without boxes. As for midrange speakers, they are made for approximate volumes that usually car doors have. As you should know, the best box for speakers is hermetical. Unfortunately we can't make doors hermetic but we can do our best. So I applied vibroisolation for the outer side of doors (much more sense will occur after looking at the picture below). Don't forget to cut small holes for the wires!

Next posts will follow!