After I use to listen to small monitor loudspeakers (I love them), I had the idea to build something bigger this time. Just in time Troels Gravesen came up with this Jenzen series of loudspeakers. And as alway's I trust his quality of design's, so I desided to give it a try:) My intention was to build this loudspeaker using AmericanWalnut wood, (different from European Walnut in color), comined with leather look baffles, and some aluminium inlay's. Why? Because I wanted them to fitt with our furniture, which is also made of American Wallnut. I like the idea of getting quality sound from (budget-) reasonable priced drivers. But I think using SEAS drivers is nothing to be a shamed of...The configuration I choosed for, comes at a 1000,= Euro's. The rest is up to you, and there is a lot to win, by making rock solid good quality cabinets.

As Troels already wrote in his article, these cabinets can't be made on a saterday afternoon. So be prepared to invest in some free time! I made some notes on the time I spend building my set, don't get shocked, I spent some 200 hours+ ! Yes seriously, but they can also be made half this time, using straight forward construction. If you follow my path, you will end up spending these large amount of working hours. But I like this kind of work, so it doesn't hurt me:) I won't show every detail in this article, because it simply would become to large. I will try to give some tips&tricks by how I got to work...On right picture, the Wallnut venere I took from my shelf and will be used during this project.

Many parts of this loudspeaker set will be made of solid walnut. If you decide to do the same, be aware of the cost of this wood. Were I live (Holland) it's not the cheapest wood! The bass cab panels will be made of assembling three 9mm Birch plywood panels together. This simply because I had a large stock of this on the shelf. It gives me 3x9=27mm+ thick panels, because of the extra 0.6mm of the venere to add. Birch Plywood is a very fine wood to use, it doesn't produce the fine dust of MDF when routed and/or sawing. All panels were custom made and venered with my book of Walnut venere. The Walnut bars on the picture left, where used for the mid/high baffle's.

As I had to glue the black leather look material arround the adges of the baffle, I had to make special formed Wallnut bars for the sides

 

 

Next page

The venered rear panel is slotted to the hole panel.

To round the holes edges I use a 3mm rounding bit. This bar perfectly fits into the routed slots which were made before in the panels. All damping materials are glued to the wood, and additional tightened by a pneumatic tacker.

Four solid Walnut bars are made, and glued on the edges of the cabinets. Damping materials are added in the cabs, now that we still have easy acces to the inner panels.

 

 

 

 

 

 

 

Left picture shows the inside double panels which I had to place afterwards. It gives this side panels a feeling if they were made of concrete. Picture below shows the 4 holes in a solid piece of Walnut for the rear side. Notice the vertical wood grain, this to fit with the venered Birch Plywood to plce above. I used solid wood here, because the holes will show the plywood inner side if used plywood.

The cabinets are glued together, only the front and back panels remain unassembled. Remove any excess glue immediately using clear water. I always use pieces of wood left over, to prevent the cabs from damage by clamping.

It takes some accuracy to make all panels fit together. Using cookies is great, but if no perfect fit is made, you will have some trouble assembling the opposite panels. The picture left shows also the front panel slot in the center. The baffle is not glue'd yet, only put together to check for fit. Front and back panels will be attached last. The tweeter section is checked for airtight enclosure. This Birch Plywood is a very fine material to work with. But prepare for a much higher price, in accordance to regular MDF sheets.

Both the cabinets, for bass, and mid/high were made adding slots to the wooden panels. This will add a lot of stifness to the cabs, and make the assembling part more easy. It takes some math and extra time to route these slots, but it will reward you. Some math is needed to semain outside dimensions of the cabs, as stated by Troels design drawings.

 

Tip/Trick;

If you by accident made a bump or scratch on the wood, you can easily repair this. Make the damaged part wet, using water, and iron it. The wood will rise, and after sanding , it will be erased.

The baffle of the mid/high cabs are coated with some nice black leather-look material, and the solid Walnut part is attached to the baffle. On this stage the mid driver hole is chamfered on the rear side. Later on wen the baffle is glued to the cabinet, this won't be possible any more.

Instead of using a 45 degrees router bit, I made the baffle angle by using my sawing table, see picture right. Importend is to cut first the angle by a 90 degrees router bit, and after that add the 45 degrees angle by the circle saw. This works very wel. After cutting the two circles, I only have to cut them in the middle. The 28 degrees angle on the both left and right sides were also made by sawing, see picture below. Accurate and safe working is of essential importance here. Always wair eye and ear protection!!