Vienna Acoustics Mahler loudspeaker Page 2
The Mahler rests on a plinth that doesn't extend all the way to the front, giving the speaker a "floating" appearance while maintaining structural stability. Three screw-in metal cones are provided to improve coupling to the floor. These are beautifully made but only 5/8" high, and would not penetrate the heavy carpet and underpadding in my listening room. I ended up using German Acoustic cones, which have longer, pointed spikes. The cabinet itself is heavily braced, with 2.5"-thick front and rear panels. The veneers (in addition to rosewood, the Mahler is also available in "beech flame," so-called because of a flame-patterned burl within the wood) are matched and hand-selected by Peter Gansterer himself, who assigns precise locations for each panel of veneer. Talk about old-world craftsmanship!
It's fairly common for representatives of speaker manufacturers to visit Stereophile reviewers to assist in setting up the speakers being reviewed. Some readers question the appropriateness of this practice ("Jim Thiel doesn't drop by to help set up my speakers!"), but I think of this practice as equivalent to the normal post-sale service that any customer should receive from an authorized dealer of high-end audio equipment. Furthermore, it's only fair that manufacturers/designers should have a chance to ensure that their products are performing as intended. Of course, reviewers must be careful during these visits to provide no clues about what they think of a product's performance, but the mandatory training Stereophile reviewers receive at the International Academy of Poker is helpful here.
In the Mahler's case, the visitor was John Hunter, well-known for his setup expertise and familiar with my listening room from his visit at the beginning of the Mozart's review period. He was quite confident that he'd have speaker setup optimized in about half an hour—an estimate that turned out to be off by several hours. Shaking his head and, from time to time, muttering "Difficult room...," Hunter listened, moved the speakers, listened again, tweaked the toe-in, adjusted the vertical angle, removed the array of RoomLenses I normally have in the room, then replaced and repositioned them. Finally, the sound was to his satisfaction.
I normally set up speakers so that they form an angle of at least 60 degrees to the listening seat, toed-in to point almost directly at the listener. John's setup subtended an even wider angle, with the speakers closer to the back and side walls than usual, and the woofers facing the side walls. The result was a huge soundstage with tremendous depth and very powerful bass. The sound was most impressive, but after Hunter had left, I came to feel that the bass was too powerful, tilting the tonal balance. I started to do some setup tweaking of my own, aimed at preserving the soundstage while getting better control over the bass. A bit of informal testing at the listening seat with Stereophile's Test CD 3 and the RadioShack SPL meter revealed a peak of about 9dB in the 50Hz region (footnote 1). I had observed similar peaks with some other speakers in this room, but not to this extent. (The smoothest bass response in my room has been with the Dunlavy SC-IV/A, which is probably a function of its over-and-under woofer configuration.)
To tame the bass, I tried all sorts of tricks: stuffing one or both of the rear-facing ports with rolled-up socks (which reduced the bass extension without reducing the peak); placing ASC Tube Traps in the corners (which only reduced the midbass, in the 200Hz range); trying different spikes/cones (no effect); switching left and right speakers so that the woofers faced inward (impairment of bass extension, little effect on the peak); adding three more RoomLenses, two of them behind the listening chair (less "room sound" from the midrange up, to the point of dulling, but no effect on the bass peak); and, in time-honored fashion, moving the speakers around.
My final setup had the speakers farther away from the walls and corners than in Hunter's initial setup, with both treble and bass switches in the flat position, two RoomLenses forming a "wing" outside each speaker, and one near the wall between the speakers. (The Mahler is provided with a removable grille; it stayed removed.) The midrange driver of each speaker was 39" from the back wall and 34" from the side wall (all measurements from the center of the midrange cone), the speakers set up along the 16' side of my 16' by 14' by 7.5' listening room. The included angle was about 70 degrees; the speakers were toed-in so that they were pointing almost (but not quite) at the listening chair. The bass peak was still there, but its amplitude at the listening position was reduced by 2-3dB. Moving the listening chair forward from its usual nearly-against-the-wall position led to a further 2dB reduction of the bass peak, but impaired center focus. I moved it back.
Footnote 1: There was no hint of the 100Hz suckout I'd observed with the Hales Transcendence Five.