when I built my Duetta Tops in March of 2012 and published my building report here on the forum, I finished by saying, “I wonder what awaits me after the MiDu expansion – I can’t wait to find out!!!” Well, when I finally got around to starting the new project, there were no more MiDus – they had been replaced by the MiDu2. So I changed my half-finished plans to work with the MiDu2, which didn’t take too long, since they are almost identical.
Since my previous constructions had been fairly simple and “normal,” this time I wanted to make something special and extravagant, given that these loudspeakers are probably at the top of the line for DIY. I wanted the cabinets to measure up. So I used CAD to design a bass section that tilted back 5° and a tweeter/mid-range chamber that tilted forward 5° to hit the listening position. The whole thing would be flanked by rounded side walls.
To make this sketched-out form a reality, I took a different path than most people do with this project. While some people glue on the rounded sides with bent wood panels or multiple thin layers, I decided to build the loudspeaker from individual segments of MDF.
On February 26, my doorbell rang and the shipper delivered the wood I had ordered, cut to the appropriate sizes. Each loudspeaker consists of 52 segments, each 25 mm thick, with an integrated bass reflex channel and reinforcements. Once the five enormous packages had been hauled up to the 3rd floor, unpacked and roughly stacked on top of each other as a test, I was pleased with the quality.
For the subsequent building of the MiDu towers, I set up a little craft corner in our section of the basement. I centered the individual slices using ridged rods, and glued them along the contact surfaces. In total, I used up three big bottles of joint glue.
The bass and the tweeter/mid-range chambers were still separate, since that made it easier to assemble the components. In addition, the two chambers would have different surface finishes. In both cases, there was still the step of sanding … and more sanding. Since I couldn’t really do that in our rented basement, I found a suitable spot in a friend’s workshop – thanks, I appreciate it!
With everything pre-sanded, I could now finally start on the surface finish. The bass body would have a shellac polish, and the tops would be finished with a rosewood veneer. Anyone who has never worked with shellac before, be forewarned: only do it if you have TIME and PATIENCE. Neither one is true for me, and I was constantly cursing myself for my choice. It is incredibly sticky, and if you’re impatient you have to do that much more sanding and touching up. Here is an intermediate step.
For the tops, I decided to use the Pattex method for the varnish, which worked amazingly well and without any problems. I applied spray adhesive to the two surfaces to be glued, let it dry for about 5 minutes, and then joined them together. The veneer sheets cannot be shifted later, but if you have four hands available, it works really well. I trimmed the overhanging edges with a box cutter as much as possible, and then sanded them with #400 sandpaper. Then I livened up the rosewood with a red stain.
I made the chassis cutouts using a router and a routing template. After what felt like a nerve-racking 154 coats of shellac, the bass bodies were finished, too. The cabinets were finally ready to go home!
In the meantime, I had soldered the frequency crossovers, and the assembly kits had long since been delivered. The terminals are made from 4-mm aluminum plates, and bent to match the curve of the cabinet on a plate bending machine.
The assembly still took an entire evening – thanks must go to my wife at this point, for her enthusiastic help.
More than half a year later, the MiDu2s have been playing in our apartment for two weeks now. In the final step, the top sections were covered with two coats of ship lacquer.
To add to the building report for the Duetta Top: what could I expect after expanding to the MiDu(2)s? I had arrived at the Olympus of loudspeakers!!
Everything that the Tops do so uniquely right, the MiDus do with even more grace and emphasis. Their effortless wealth of details across every frequency, without the quieter notes being overshadowed or even swallowed up by the louder ones, is very impressive, and it makes me incredibly happy. I enthusiastically listen to all kinds of music – classical, blues, soul, folk, rock, pop, hip hop and electro. After two weeks of extensive listening, I can confidently say that all of it is fun!
The Blues Class plays more than just blues and jazz at a high level. I can only recommend the MiDu2 to any listener who wants to play “modern” music and really let it rip – it’s a true experience! It reproduces singer-songwriters (like Agnes Obel, Bella…) and their quiet, delicate tones in an incredible way that I have never heard before (at least not under 30,000 euros).