TL's elektronik ting og sager
Dual Scan-Speak 32W/4878 13 Inch DIY Subwoofer
I built these three subwoofers together with my son Jonas who helped me complete the boxes. It was a very long-term project, because wood is not my biggest interest and therefore I could always think of making all sorts of other things than this. Luckily my son is really good at wood and he also finished his carpentry training while the project was underway. Lucky me!
I do not want to say when I started to plan and build these subwoofers, but rather when they were ready - almost ready, because they are not quite finished yet. They were supposed to be active with built-in amplifiers and correction filters, but unfortunately I have not reached that yet. There was not enough time and there were other things to do first. But they were as finished as they are now on 20180826.
They were going to replace my old subwoofers that I built many years ago. They were built with a very powerfull professional 18" Beyma driver, but did not go as far down in frequency as I would like. Then I found these cool Scan-Speak 32W/4878T00 drivers and decided to build three dual subwoofers with them. They are 13" and works very well in a closed box which was what I wanted.
The most important thing for me was that they should go far down in frequency and at the same time have a solid and steady bass. The sensitivity was not so important because I had plenty of power from my amplifiers. I must say I was very surprised when I first heard them. They are very powerful and have an incredibly deep and steady bass. You can clearly hear if someone has walked around in the studio with some musicians. Something that can not be heard on quite a few speakers. One of the coolest experiences is from the movie Interstellar where they fly through the black hole. It's wild!
Below are some mixed images. If you are wondering about the small Yamaha monitors, it was only in the beginning they were used. I had nothing else at the time. I have some others now that fit better, and I'm making new ones that fit the subwoofers. It's also with Scan-Speak drivers. All the pictures on the page are made as slide shows, so click on the arrows to see the pictures. There is about 200 pcs.
Internal Cabling
I have used 8-pin Speakon connectors for the woofers. In that way I can connect each driver separately and choose whether they should be connected in parallel to an amplifier, or whether they should have one each. Four of the pins in the connectors are used for the two drivers (from amplifiers to speakers) where I use a good quality 2x4mm2 OFC litze cables. The last four pins are used for feedback signals from the speaker terminals to the amplifiers. This gives the advantage that the cable can be included in the amplifier's feedback loop and then it can be totally out balanced. Then the resistance of the cable has no significance and it seems exactly as if the speaker is connected directly on the amplifier with 0 cm wire. In this way, the ultimate damping factor is achieved. The plan was that I would build some cool amplifiers and build them into the back of the boxes where there is a chamber to be used for it. I have not had time to finish it yet, but maybe one day. Right now they are working just fine with an external amp.
Cable Assembly
Here are the cables as I made them. Please use the arrows and see more pictures.
And here are the front frames.....
Assembling before painting
Assembly, adjustment and grinding of the boxes with great help from my son Jonas. Please use the arrows to slide the pictures.
Drawings
Here are some of the drawings that were made before we started the project. The first ones were just quickly drawn with a pencil. Please use the arrows to slide the pictures. You can download the pdf drawing here PDF
