First conceived in 1968 the DM Model 70 was the first 100% in house designed and built monitor from B&W. It is rare and largely forgotten, this is not how things should have been.

My pair of white Continentals (1975). Click to see a larger image.For those of you who don't know it, the DM70 went into production in 1970 and was manufactured for at least six years. It is a hybrid of moving coil and electrostatic loudspeaker technologies, it was expensive to develop, produce and ultimately to own. The technology was unique at the time of manufacture, we like to call it an "E-brid". The system basically comprises of a 12" bass unit in an infinite baffle arrangement plus an eleven segment curved electrostatic panel mounted on top of the cabinet so as to handle the mid - high frequencies. There is an internal PSU for the panel and a highly complex crossover to marry the two drivers together. The crossover frequency is set at around 400 - 500 Hz so as to avoid colouration of critical midband frequencies. There is minimal intermodulation distortion created by the two technically different drive units.

Enigma Variations

I believe the B&W DM 70 monitor to be very special, why have they been forgotten? I have been surprised how little reference this model has received within the audio circles of which I am familiar. Search Google, no websites, no fan clubs, almost as if they never were! It is a complete mystery to me why these speakers aren't given the same kudos as a LS3/5a or a BC1 (sonically the floor is wiped with most box speakers). These truly are an enigma!

First Contact

Amar Bizwas (Eminent Audio) had a knack of aquiring esoteric audio items long before we were all busy searching ebay pages for fulfillment of our vintage audio fantasies, he had bought his second pair of Model 70s after a lengthy search. He had owned his first pair in the early 80's and when the second pair came along three years ago I was told of ultimate build quality, over-engineering and holographic soundstage merged with prophecies of possibly the best loudspeakers that B&W had ever built.

Unfortunately for Amar his second pair had lost their original bass units. Alternative drivers were sourced and Glenn (Croft) helped to tune the crossover in order to make them work, I was disappointed as I was convinced that I had missed my opportunity to hear legendary loudspeakers from an era of British audio where the accounting bean counters were not allowed to impede the work of loudspeaker designers and sound engineers. Sonic integrity is a massive part of the design of the these units and the cost of attaining it is possibly part of their demise.

Sound at the end of audio tunnels

My opportunity came about eighteen months later whilst browsing ebay pages. The owners were a couple who were fans of 70's design that happened accross them at a house clearance market in Tunbridge Wells (England).

Click to enlarge viewIt is safe to say that they did not know what they had and were not especially into Hi-Fi so the speakers were sat in a house amongst other 70's icons for five years without actually ever being used as loudspeakers. This was just as well, as the bass units were in need of professional attention (see Refurbishment). However, my fellow ebayers were aware of the vintage of these loudspeakers and winning the auction did not come easily.

These loudspeakers really are special. Please read the following pages in order to get the whole story.

Thanks for your interest, Matt.