Delta 3 - Construction

Gone is the bass section of Delta4. Delta3 is the the combination of Delta4's satellite combined with the Samson enclosure as the bass section. The 10" bass driver will be still be the Scanspeak 26w8861 as used in Delta3. Overall the eclosure is much smaller (lower and smaller footprint) than Delta4.

New low diffraction grills have been made and for greater security (child proofing), the magnetic attachment has beem eschewed in favour of the standard type of grill clips. The satellite grill frame is made from a single piece of 5mm mdf, the bass grill is made from tasmanian oak wood mouldings,


Painting the enclosures was a long process. The veneered satellite and enamel-coated bass section were first sanded back and painted with an isolator primer, to provide the necessary base for the acrylic top coats. After 3 coats of isolator and sanding with 400 grit, 3 coats of acrylic primer were applied. Then 4 coats of the cream-coloured automotive base coat (called "lace") and then 10 coats of acrylic clear coat. The acrylic coats dry very fast and allow new coats every 5 to 10 minutes.

Once all the painting is complete and left to harden for 24 hours, polishing of the clearcoat could begin. First, sanding back with 800 grit, then 1200 grit. Then Kitten number 2 cutting compound, followed by number 1. The final stage is Kitten waxing and polishing, just as you would do for a car finish.

The plastic grill sockets were first primed with a plastic primer, and then followed with the base and clear coat steps.

Overall a very time-consuming and expensive experience.

Here is a closer look at the bass section, showing the additional bracing and 36mm base (painted black) that I've added.
The new crossovers. Most capacitors are Solen, except for the huge Mundorf Supreme on the tweeter section.
Both enclosures are lined with wool-felt and lightly stuffed with lambswool.
The crossovers are held in place with velcro. Foam gaskets line the rear panel mounting.
The rear panel with variovent installed.
Lightly stuffed with lambswool.
Spiking the bass section. The front spikes are adjusted 5mm higher to give the speaker a slight back tilt to improve time alignment. It also brings the tweeter to ear level.
Finally, after about 6 weeks work, in the middle of Melbourne Winter 2007, Delta3 construction is complete.
I've applied some felt circles around the tweeter to reduce diffraction effects from the edges and grills. The positioning of the satellite on the bass section is 15mm back to further assist in time alignment.