A firm(er) foundation for the Alumine 5
By Roy Gregory
Stenheim first introduced a heavyweight base (denoted with an SX suffix) for the Ultime 2 loudspeaker in 2023. It brought welcome stability to what is both a heavy and a top-heavy speaker. It also brought a surprising lift in performance. (https://gy8.eu/review/steady-on/ ) The following year saw the arrival of a simplified SX base for the Alumine 5, a sculpted block replacing the two-part cruciform structure of the U2’s version. It still cost a far from trivial $14,000 USD, especially when compared to the price of the $76,500 A5-SE to which it was attached. Without the physical and stability challenges that face the U2, the A5-SX was all about performance.
It certainly made an impression, from the added ease of set up, to the increased transparency and linearity in the bottom end and on to looks which are perhaps, most charitably described as ‘divisive.’ Having said that, I’ve yet to find anybody, apart from me, who admits to liking the appearance of the A5-SX – although history tells you that my view represents no recommendation. Now, almost a year later, I’ve actually laid my hands on a pair of the A5-SX loudspeakers, with a chance to hear them and assess the sonic and musical impact of the SX base in my own system.
The speakers arrived in their swanky new, three-part flight cases (LINK) along with a pair of large and surprisingly lumpy cardboard cartons. Which brings me to the most important thing about the new foot. Like the base designed for the U2, the SX base designed to match the A5 is an add-on. It can be bolted on to the bottom of any, existing A5 loudspeaker, making this both an upgrade opportunity as well as what amounts to a new speaker model.
Open the cardboard carton and you discover that it encloses a solid block of resilient foam packaging that completely fills the interior, preventing any movement by the contents. Lift out the top layer of the foam and the reason for the extravagant packaging becomes obvious. Nestled in the middle of the lower section is the SX base, a 39kg (86lb) chunk of machined aluminium with stainless-steel hard-points and brass inserts. If that starts moving in transit, it ain’t going to stop… Arrayed around it is an impressive set of parts and tools: two sets of massive, 30mm diameter stainless-steel spikes (you can order long or short to suit different flooring), matching stainless-steel footers; white, delrin, domed floor protectors that can screw over the spike tips to aid movement and installation; colour coded caps to cover the spikes from above, once adjusted; a set of casters to allow the speakers to be wheeled for longer distances (once you’ve added those 39kg to their already substantial weight, you aren’t going to want to carry them); all the bolts and tools required to install and adjust the base, including a shortened allen key to fix the casters and an engineer’s ruler to help set speaker height. You even get a pair of large allen T-bars, so that you can adjust pairs of spikes on a single axis simultaneously, along with a comprehensive installation manual.
