PS AUDIO: Experimenting with planar loudspeakers: first with Magnepans and later with electrostatic loudspeakers – specifically the Acoustat 2+2

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Paul McGowan writes:  In the late 1970′s I began experimenting with planar loudspeakers: first with Magnepans and later with electrostatic loudspeakers – specifically the Acoustat 2+2 which happened to be tall enough to qualify as a line source.  If you’ve never heard an electrostatic loudspeaker then you’ve missed out on an amazing experience – albeit one that is very limited – that of a window-like quality of “you are there” midrange.

We used to joke that with an electrostat you had to have your head held in a vise to enjoy the benefits – so narrow the sweet spot of these products.  But when you were in the zone they could be rather amazing – so light is their diaphragm that their transient response is nearly instantaneous.  They had other faults and benefits as well, chief amongst them was a lack of dynamic range and bass.  It was to this latter quality I address this post.

After acquiring the 2+2 pair I quickly became unhappy with their limited dynamics and low end and was ready to sell them and move on when by chance I happened to be standing next to the panels when they were playing.  I noticed that standing next to the speaker there seemed to be an enormous amount of bass present that apparently wasn’t being projected into the room.  Instead, the flimsy wooden panels were themselves wobbling to the bass and hence little of that energy was being transferred into the room.

The solution seemed obvious: brace the panels so they didn’t move and the air in the room did instead.  To do this I built a bracing system out of 2×4′s and screwed it into the panels – a good solution but ugly and much to the horror of my ever loving and forgiving wife Terri – as these were in the family living room.  I lived with the improved results for some time but eventually hated the look of this contraption as well and dismantled it.

I decided it might be worth while to augment the bass instead – with a subwoofer – of which at the time there weren’t too many of any quality.  I happened to have a low cost M&K sub hanging around and added this to the right side of the system – the right side being the correct side always when a single sub is chosen because of where the bass instruments reside in an orchestra.

I spent the day moving the sub around turning the volume up and down and could never quite get the thing to integrate with the panels – until at one point in my adjustments I nailed it.  It integrated perfectly!  True, in this setting there wasn’t much bass but dang if it didn’t integrate seamlessly with the panels.

It was when I went to the rear of the sub to write down the volume setting that I noticed I had actually set it to zero.  No wonder it integrated so seamlessly.

I put the 2+2′s up for sale the next day.