... it was set up when Evolution designer Radovan Řehořek and marketing manager Martin Landa flew in from Prague to install the Voxativ AC 1.8 wood-cone option, then use the existing one-way packaging materials and plenty of straps to ready the pallet for pickup the following week. Arriving with a cleverly modded flight case for on-location testing, Radovan took quick 1-metre measurements of the installed Fostex. Those did not look as intended. It explained why I'd experienced premature bass attenuation and why I needed the Oris. When Radovan uninstalled the Fostex, it became clear that someone had forgotten a roll of absorptive liner behind the drivers which they sometimes pack for transit protection. This roll was a block in the horn throat. And that interfered with the rear horn's proper function, making me think its geometry was ineffective when in fact, it was unintentionally obstructed. Hindsight makes smarter.

After removing the obstacles which had strangulated intended rear-wave augmentation, the Fostex FE-206En in this cab did proper fulsome bass, requiring no subwoofer assist to complete it.

To install the Voxativ required drilling new holes slightly closer to the opening's edge. Using a jig that screwed into the existing threaded receivers, Radovan had the 1.8 mounted in no time. For customers intent on driver not partner swapping, RDacoustics will of course prep the Evolution with all necessary fittings prior to shipping. Even with multiple bolt inserts, the bull-nosed trim ring or Oris horn will always disguise that hardware. At first I heard the Voxativ with the oak horn since that's how the Fostex had played just before the swap.

The Berliner's thermometer immediately shot up in the treble (more extension) and midband (more substance) whilst the bass wasn't quite as extended. However, this driver was noticeably smoother in the critical upper midrange. By contrast, the Fostex was more ragged and energetic. The Voxativ was mellower and more suave. Comparing it with Oris on/off, not only did the front horn bundle the sound for a more focused but narrower soundstage again, its slight gain above the bass registers now caused a minor discontinuity to my hearing given that the bass wasn't as extended as the Fostex. I thus preferred the Voxativ straight, filling in the very low end below 40Hz with the Zu sub instead. Being simple push-on choices, a shopper fine-tuning this aspect needs no tools. Pop on and off. The effect of the oak horn will be immediate. What you prefer can't be predicted. Trying it for yourself is a must.

As the next photo shows, I'd already moved the Evolutions deeper into the corners and one tile closer to the sidewalls to invoke a bit more boundary gain given the room's size. Fronted by the tubed Fore Audio DAISy1 converter and using Vinnie Rossi's Lio as autoformer attenuator, the 15wpc Bakoon amp with 1MHz bandwidth acquitted itself very well, exhibiting zero noise or glare yet playing up the aspects of immediacy and lucidity. Once again the Evolution played it big with regard to virtual performers, flowering bass more rotund and bloomy than cut and dry.

In the second octave above middle C I did hear the occasional forwardness when a particular player deployed dynamic emphasis to have certain notes stand out more. It's this freshness which can translate as nonlinear dynamic contrast—more in the upper vocal band and presence region, less in the upper and mid bass—and give this type speaker its uncanny vividness and also its reputation as temperamental diva. That the Evolution did so well with a 'speed-freak' amp of Bakoon's calibre showed how well behaved this tendency was. It was present and part of the appeal, not pronounced enough to cross from minor character into standout flaw. With a traditional valve amp, one may not hear it at all.

In closing, the major attraction of the Evolution has got to be the freedom inherent in its big breathing gestalt. Instead of sounding tied down hard with comealong winches whilst sucking air through a narrow port tube (let that image settle in!), the Evolution with its large horn mouth and single driver behaved like an enormous heaving organism blessed with huge lungs. Freedom elsewhere includes imperfections. Passion is always messy, the saying goes. Rigid discipline might eliminate imperfections but kill off all the fun while at it. Similarly, the Evolution's free gestalt played it a bit looser on perfect amplitude linearity or equal damping across the bandwidth (less with descending freqs). The payback fun of not using a xover and multiple sound sources was the huge scale and easeful gush. Because of this scale and the big buoyant images, I'd prefer sitting at least 4 metres away. Add man-size height. To my mind, this tall speaker deserves nay wants a larger space to really let its hair down and not overwhelm you acoustically or visually. Whilst the Voxativ driver option does increase the layout by 50% over the Fostex, I heard it as operating on a higher octave of refinement. Add new veneers and colourful lacquers about which I was told that Germany had just ordered a pair in grey lacquer with orange leather to match a client's couch and Bauhaus aesthetic. Like a multidimensional puzzle, the Evolution with its driver, phase plug, front horn and cosmetic trim options really does seem as close to custom as loudspeakers can get before you must build one from scratch. Lest you thought that a trifle, the Evolution went through twenty actual prototypes not computer simulations before arriving at the final geometry and tolerances for its enclosure. The puzzle aspect makes it different from all the Frank Sinatra boxes—my way or the highway—where one designer locks it all in on your behalf. True to its name, the Evolution is a moving target. You decide where you want it to stand still. You even get to change your sonic mind well after the fact by rolling drivers, phase plugs or trim ring vs. Oris horns; to suit a new mood or act as refresher antidote to boredom from sameness. It's an open secret to which tube rollers have glommed long ago. But how many speakers let you roll actual transducers? That only works because there is no crossover to change as well. As our Swiss friend Marco would triumphantly say, "it's a roly poly, man!"

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