two way v. three way speakers


I recently heard some magico mini's at a friend's house. They sounded amazing. And they were 'only' a two way speakers, but they filled the room with amazing sound. So now I wonder, what does the additional driver add, especially when it is the same size as the second driver. For example, the SF Olympica III's have two drivers of the same size. I know that third driver adds a lot to the price, but what does it sonically? Thank you all in advance.
elegal

Showing 1 response by phusis

For a long time I associated 2-way speakers mostly with smaller, stand-mounted incarnations with all that generally entails; lack of bandwidth/force downwards and overall sense of physique, mids that were somewhat affected at higher SPL's and the limitations of the latter this also implied (i.e.: lack of effortlessness more than max. SPL per se), lack of (a more natural) sonic size, etc.

My latest speakers though, to my ears, have bridged the typical qualities of 2-way speakers with the ones found in larger multi-way dittos in combining coherency and focus with an effortless, forceful representation - indeed adding to the qualities of these two "camps" as they are usually found here. Very generally the smaller representatives of 2-way designs cross between 2.5-3.5kHz, indeed in a similar fashion in this region compared to 3-way designs, only to have the latter add another cross-over in the 200-400Hz region. One could argue, I suppose, where the sensitive frequency spectrums are most pronounced when crossing over from one drive unit to the other, but both 2- and 3-way designs typically seem to have problematic encounters in these frequency areas, at least compared to a 2-way design that crosses around 1kHz - give or take. Dome tweeters don't go this low, unless assisted by a waveguide - a configuration that could also house a compression driver instead, and this is a combination in particular I find very successful.

Anyway, a 2-way design crossed in this fashion at or below 1.5kHz down to about 700-800Hz seems to bring out a very nice compromise with two drivers used, and moreover the waveguide adds a much needed sense of physicality (air displacement area) that makes it (potentially) couple more fluidly with the bass/mid unit. Energy coherence, anyone? Lately I've never been able to bring my ears around the limitations of direct radiating dome tweeters; they simply sound malnourished, thin and strained compared to a well-implemented waveguide design, particularly where a compression driver is used.

As "hifi" goes a midrange above or even at 8" is usually a no-go, and this seems to be an effect of these type of lower sensitivity drivers being low-fs bass units as well; they simply run out of energy steam even in the lower mids. Where more sensitive drivers are used a 12" more or less pure midrange with lighter cone movement is not uncommon, on the contrary: one that brings with it some very interesting implementations with beforementioned waveguides. The more obvious compromise here is lower bass, and this calls for the aid of preferably a pair of subs to assist below 80-100Hz, though designs could easily go without sub assistance if one isn't craving for sub-bass terrain. Indeed, that so many speaker designs slavishly go for lower bass extension to compromise the lower to central mids presentation is beyond me.

To my ears and via above mentioned design preference I'm very obviously for 2-way designs. Once getting used to this it's hard to feel convinced by the sound of multi-way designs, not only in this area; they simply sound "out of phase/focus" and don't gel favorably. And when you got the typical traits of the larger 3-way designs in addition, in more than full measure, there's really no turning back.