Epos ES25 loudspeaker
Apparently, Epos also wondered how they might improve upon the performance of the remarkable little '11. The key change had to be additional deep-bass extension. Deep bass would require more internal volume—a bigger box. In all likelihood this would also provide the necessary vehicle for added spls.
Since the midrange and treble performance of the '11 had been universally accepted, it appeared that Epos had decided to leave well enough alone while building upon the essence of the smaller speaker: the new ES25 uses a 6.5" polypropylene-coned midrange driver that is described as "a development of the successfully established ES11 bass/mid driver." Like the '11's drive-unit, the '25's has a wet-wound voice-coil, a phase plug instead of a dustcap, and a center pole-piece which extends beyond the top plate. Where the 6.5" unit was reported to reach down to 60Hz (–3dB) in the '11, it is crossed over at a higher frequency in the '25. By taking the burden of producing the deep bass off this drive-unit, it should be capable of outperforming the ES11 in the ever-critical midrange.
My supposition was buttressed by the '25's 1" tweeter. Like the '11's, it has an aluminum-alloy dome, polyamide suspension, a separate rear-loading chamber, vents in the coil former, and magnetic fluid in the magnet gap.
So, if not identical, the mid and treble drivers still bear an unusually close similarity to those used in the '11. That was to be expected, since Epos makes all of their own drive-units.
One of the critical factors in the design of the ES11 was the use of a "minimalist" crossover topology. The underlying supposition was that the fewer components in the signal path, the better. This philosophy has been carried over to the ES25, but not without some measure of compromise. Since the design, development, and production of the drive-units were all under Epos's control, they were made within strict tolerances. For example, the tweeter, like the '11's, needs only a single audiophile-grade capacitor in its signal path to produce a first-order, 6dB/octave slope. In addition, the rear of each cabinet has separate connections for each drive-unit for tri-wiring. Music Hall supplies jumpers for single wiring; if these are used, Epos/Music Hall suggest direct connection to the tweeter instead of to the midrange (the expected choice). The connectors are brass female Deltron types that can accept banana plugs. This is one area where I was disappointed; I feel that for the US market, five-way binding posts should have been included.
To give deeper bass, higher output, and more dynamic presentation, the '25 had to have a bigger box as well as an additional driver. The all-new woofer is an 8" (the same size as the bass/mid driver in the ES14), long-throw, vacuum-formed Cobex cone with an internal dustcap. It is housed in a separate, reflex-loaded sub-enclosure with a rear-firing 2.75" port located near the floor. The mid and tweeter drivers are housed in their own sealed box. A second-order, 12dB/octave low-pass filter is used to roll out the upper range of the bass driver's output. The –3dB down point for the bass driver is specified as 25Hz.
The net result of these evolutionary changes to the well-developed ES11 is a three-way, three-driver, floorstanding loudspeaker—all pretty radical features from a company whose well-deserved reputation has been based upon minimonitors. The cabinet is lovely, and appreciably superior to the fit and finish of the smaller, more industrial-looking ES11. The front baffle was smooth with no rough edges, open holes, or other visual distractions. The edges were nicely rounded, and the wood veneers were arresting.
The speaker is unobtrusive at about 35" high and less than 10" wide. Given the speaker's light weight and small size, it was easy to place and move about once in the listening room—even after the floor spikes (four for each cabinet) were in place. All things considered, it was about as flexible as any floorstanding loudspeaker could be. While grillecloths were included, these were not much more than afterthoughts and I left them off for my auditioning.
The envelope, please...
Because prior Epos speakers have been so wonderful and their product introductions so rare, I was eager to audition the ES25. My initial impressions were very favorable: the '25s were able to create a huge, expansive sound with orchestral recordings, generally placing the performers behind the cabinets, but in or just beyond the rear wall. The open-sounding presentation was positioned above the smallish floorstanders.
Initially, the tweeter's clarity stood out from a slightly recessed midrange and muddier, woollier bass (something I often experience with ported boxes). The sound was musical overall, with no distracting amusical elements added. The sound tended to be a bit warm, if anything, and did get slightly muddled when pushed. Of course, this was all before any appreciable break-in.
As I let the speakers break in, I spent many evenings with my Magnum Etude tuner, searching for new music, new artists, and impressive new performances of familiar works. At low-volume listening levels late, late at night, I was gradually seduced by the '25s. They simply got out of the way and let me concentrate exclusively on the music.
During this time I tried numerous amps and cables with the Eposes. When I changed other pieces of equipment, it was relatively easy to hear different soundstage presentations, tonal balances, levels of detail resolution, and any number of other things. (It was during this period that I became particularly pleased with the NBS Master cables, which became a staple in my system for the rest of the review.)