Single driver loudspeakers


I know some friends who have built single driver horn loudspeakers with 6-7 inch 'full range' drive element and seem very happy with the sound.  However I wonder about those selling 94 db sensitive 12 and 15 inch full range drive elements and recommending 2-3 cubic ft bass reflex cabinets and 7 watt SET amplifiers.  Is it possible for a 15" 'full range" driver driven by 7 watt SET  to provide state of the art sound without audible distortion, deficient frequency extremes and 1950 style sound?  This is an inquiry not a critique.  Thank you for helping me to understand full range drive units.

normie57

Showing 2 responses by rlawry

I have had some very expensive multi-way speakers and when starting to design my own I saw some single driver speakers, so I bought a pair of 8 inch alnico Audio Nirvana drivers and had a cabinet builder make cabinets using the design shown on the Commonsense Audio website.  The alnico magnet drivers had a much smoother frequency response that that of ferrite and neodynium magnets.  I was completely taken aback with these, especially when mated with my JL Audio subwoofer, which completes what I consider the only real achilles heel of single driver speakers:  bass dynamics.  They can certainly plumb the depths but cannot move air like real woofers and subwoofers. So I then sold these and bought the AN 12 inch drivers and a larger (5.6 liter versus 2.8) cabinets, and they are a significant step up in most parameters.  As far as treble, after hearing these I wonder why anyone makes tweeters, even approaching the sound of the ion tweeters in a pair of Acapellas I once had.  And the midrange is simply unreal, as well as soundstaging and immediacy.  

I unfortunately cannot answer your question about the low-powered tube amps you mentioned as I use as powerful solid-state amp and a tubed preamp and phono stage.  I would think the tube amps to be a good match with the high sensitivity and easy load of the speakers.  Remember, your amp is driving the speaker voice coil directly, and IMO, I can hear what multi-way speakers with crossovers do wrong.
What a number of single-drivers incorporate to improve treble performance is a whizzer cone and phase plug.  Recently there have been developments that preclude such a design.