DVC Collection - Bozak MB-80 - Restored by David E. Cox

DVC Collection - Bozak MB-80 - Restored by David E. Cox

Overview

These superb bookshelf speakers were designed in 1979 by Peter Ledermann at Bozak in South Norwalk, Connecticut, USA.

What makes this speaker so special is the selection of drivers and the build quality and size of the sealed cabinet they are placed in.

The tweeter is a French-made soft dome Polydax (Audax) HD 100 D 25 A, a driver selected by other well known speaker manufacturers, notably Spica, who placed it in their venerable TC-50.

The bass driver is a 6-1/2" 209-W, wide-range aluminum driver designed by Rudy Bozak and modified by Ledermann, weighing in at 3.2kg, of which a hefty 2.6kg is attributed to its massive, oversized magnet. Ledermann called it "an ultra wide bandwidth performer" and, though a driver of its petit dimensions can never plumb the deepest depths of frequency, the bass it produces out of its sealed enclosure is punchy, tight and surprisingly prodigious.

On the front baffle is installed a small, automotive-style lamp, which is connected to the tweeter circuit. As an alternative to a fuse, the lamp acts as a protection, absorbing excess energy and emitting it as light, thereby protecting the tweeter from being overloaded.

The cabinet is made of 19mm dense chipboard and due to its dimensions, there is virtually zero resonance, meaning the cabinet contributes negligible colouration to the sound.

The finish is American oak and David opted to fill its grain and finish it with 6 layers of polyurethane and hand polish it to a gloss finish.

All electrolytic capacitors on the first-order crossover had perished so they were replaced with Dayton film types.

New nickel plated 5-way binding posts were installed in place of the original plastic ones.

Originally, on the front baffle, were mounted black plastic lugs by which to affix the grills. David considered these ugly so, in keeping with the metallic look of the bass driver, he lathed new lugs out of solid stainless steel.

The original grill fabric was a dull, 70’s-style brown, which was replaced by premium cream fabric from France and imported by Sound Labs Group.

A quote from Peter Ledermann regarding the MB-80’s:

“One of my great joys occurred when I first demonstrated these speakers at a CES show. I had positioned them on some unique adjustable wooden speaker stands I engineered, in front of Rudy’s classic Concert Grand Loudspeakers, which [...] were each the size of an industrial refrigerator. The imaging in three dimensions from these miniatures was so astounding that all those who walked into our suite were convinced they were listening to the old huge loudspeaker classics, each comprised of 8 slot loaded aluminum cone tweeters, two 6” aluminum cone midranges, and four 12” variable density woofers.”