As it is only proper, the FirstTime 1 will start the practical guide of the Loudspeakerbuilding magazine. Since in the introductionary article har hardly any chance to explain certain aspects in detail, we will do so in 3 aspects. These are construction, installation of the cross-over and the construction and application of a cover.
The building material, regardless if it is MDF, chip record or Multiplex, can be cut to sice cheatply either at your local hardware store or with a carpenter. Afterwards you will come home with a puzzle of boards which will have to be sorted according to the construction plan by yourself.
Before we begin with the assembly, we draw a few auxiliary lines on the board which will be the side f the speaker. Thus we know later where the other boards belong. Then front and lid are glued on shortly.
To convey an idea of the dimensions, we have put the tube of joint glue in front of the box with the back wall glued in. In the right picture the base and the lower TL board are already glued to the visible auxiliary lines.
The rear TL board and the lower front board complete the inside construction. After the glue has dried under the board for the second side, the box gets sanded, the cuttings are sawed and the edges get rounded off for a nice look.
The next step after sanding, milling and varnishing is the correct installation of the insulating material, the cross-over and the chassis.There is not much to be kept in mind, one only has to do everything right from the start, then in the end the sound will be great too!
With blue glaze I gave to the FirstTime1 a look which would not immediately betray it to be MDF. Into the base and rear TL board I drilled two holes with a diameter of 8 mm through which I led the cables to the chamber for the cross-over. Hot glue seals the openings afterwards.
A stripe of the insulating material each fill the rear and front line department. In the outlet the material is folded under the bass, so it lies a little more firmly. The cables still lurk patiently in the responsible cuttings....
... for the chassis. The midrange chassis are soldered in parallel, where a cable from lower leads to the upper partner. The positive poles are marked red. The other end of the signal supply ends in the frequency points which are connected for their part with the terminal. By the upper hole she reaches the tweeter, by the lower one the basses.
An frequently used argument not to bilud a Transmissionline is the fact that the sound wants to exit through a rather big opening. It is very usefull for the quality of sound if the opening is in the front of the speaker. Thusly the view on the insulating material is possible. To build a cover in order to prevent that, we made the following instruction.
The Basis for our cover of the hole in the front that is considered ugly is 10 mm of thin MDF wood in the dimensions of the missing front record minus1 millimetre for the cloth. Of that we only kept a frame of about 1cm, the rest was discarded. The black,opaque cloth that will be covering the hole, that is no barrier for the soundwaves is layed under the frame and cut to size generously.
A stapler with 6 mm of clips is sufficent to nail the cloth to the frame. We begin on a side and stretch the material a little when we work on the subtending one. The material receives the right tension with the bolt on of the last sides. While working on this we spared the corners.
The material is bundled together on the corners rather firmly and is pulled tightly about the edge. We pay attention to the fact that no folds are created. From two to three clips give hold to the black cloth.
The scissors will do the rest. Who cares to have a pretty rear too can take a metal ruler and a carpet knife and cut the spare. For the case that the clips are too far apart the material will quickly loosen. A few additional clips know how to prevent this
Should the frame sit too laxly in the hole, he can be "widened" with one or two more clips at the side. This small trick is not unlawful of course, one must only know how to help himself!