ScanSpeak Illuminator-5, built by Brian, US
Copyright 2018 © Troels Gravesen

Salutations Troels,
 
I hail from the Bay Area of California. I built the Illuminator 5 design to your specifications as much as I possibly could, and I would like to share my experience with the sound and the construction process and maybe give you some satisfaction in knowing that you inspired the project.
 
This is the first speaker cabinet system that I have ever built, so some mistakes were made along the way, of course. But it turned out pretty much perfect as I compensated for all of the minor inconsistencies that came about. First off, anyone who is planning on building this cabinet system can predict at least 150+ hours will be necessary to fully complete it; and around $6,000 USD. If you choose to build it just the way I did, then more power to you, but it will likely take you an extra 120 hours as it did for me; total around 270 hours of labor. But the fruit of this labor is absolutely heavenly sound that I can enjoy for the next 50 years or so, and I am greatly satisfied with the result. I may even try one of the Ellipticor builds at some point.
 
For this project to succeed, I needed about five 4'x8' panels of MDF at around $30 each; $150. There was a lot of scrap from mistake cuts and from not actually having the full size panels to work with; I needed each MDF panel divided into three sections to properly fit in my sedan. I am decently experienced with basic carpentry; making square shaped constructions. But the angled cuts in this design take the difficulty to a whole new level. The pay off is well worth it though. I love that this build has angles to its shape and that is why I chose it.
 
You will also need some screws for the speakers, which amounted to about $20 USD to get the proper sized screw for each individual driver.
 
And if you want your build to look like mine, then you will need about 45 lbs (20 kg) of copper sheets; cost me around $300. And a quality pair of metal snips is essential too; around $20. I also chose to polish the copper, and I already had a $100 angle grinder, so I only needed to buy some polishing discs at around $25 and some polishing compound; I used almost half a kilogram of polishing compound on the copper. You will also need some good quality construction adhesive or wood glue to fasten the copper sheets to the body of the cabinets; I used wood glue about two gallons at $40.
 
Also, I have some advice for the legs. Making them with the standard metal inserts into a hole drilled into the wood product was not a very satisfactory or reliable option for me, since I knew they would be put under considerable strain from being moved around during the next 50 years. Instead of the traditional method, I put four large washers in each corner of the inside of the bottom of the cabinet and then I drilled holes in the center of those washers; I had two panels on the bottom of the cabinet for about 3.81 cm of MDF material. I then put four nuts and washers on carriage bolts and put them through the holes from the bottom of the cabinet into the interior. Inside are the washers that I still had in place and I clamped down on each side of the cabinet by tightening the nuts which when combined with the washers act as a very robust weight distribution system that ensures that the cabinet will not break or be damaged by any sideways force against the bolt; e.g. when tilting or moving the cabinets. When using this method, you are also able to adjust the height of the legs at any time, but loosening the nuts and twisting the carriage bolts. I used some rubber feet to cover the carriage bolts.
 
Of course, you will also need to have quality soldering equipment and solder for the crossovers; I went all out and got a high end Weller system for about $120 and about $10 for the solder. Then you will need some adhesive to attach the crossover components to your board; I used a high quality Loctite Fuze-It adhesive for about $7 a container. I used two containers.
 
Also, it is optional, but if you want to install an easy maintenance hatch for the crossovers, as I did, then you will need to buy some hinges and your choice of latch; I chose a few simple bolt latches and had no problems.
 
The total weight of the cabinets came in at about 150 lbs (68 kg) per cabinet, drivers and all.
The most costly components will be time and patience, but trust me, in the end your ears will be thanking you for the work you have done.
 
The sound is absolutely incredible. I have never heard sounds from music at such a high volume and such a perfect clarity. Even at low volume, I am able to discern all of the most minute sounds without difficulty. The bass is a mindblower. I have never heard the low frequencies of a bass coupled with a properly braced cabinet before. There is absolutely no rattling noise at all. Imagine the exact opposite of this in the most common form that you will come across: cars installed with aftermarket bass systems. Usually, when I hear the amount of bass coming out of those cars, the most obvious noise is not the deep melody of the bass, but the harsh rattling of all of the components that are shaking in their car. It is not a good sound, but instead just a loud sound. Cars were not built to be speaker cabinets. In this system the bass moves through you without overpowering the soundspace and you hear all of the low frequencies distinctly and smoothly. Often it feels as if I am totally enveloped in sound, and unless I am focusing I cannot pinpoint exactly where it is coming from. And the high frequencies, the tweeter sounds, those are a lot easier to manage with minimal bracing, but even the lower mids are properly braced in this system so there is absolutely no rattling and all of the sounds come out tight with distinct audible gradations in each frequency of sound. There are subtleties of sound that you can't hear with lower quality loudspeakers. There is approximately zero audible distortion at any volume. There is no static unless it is recorded on the sound file itself. I have yet to try the speakers at their absolute maximum volume because it is just painful. I have turned it up to the point where my ears were hurting but the music was just as clear as normal listening volume. I will be enjoying these for many years to come!
 
Mange tak,
Brian