County Durham's speaker maker for more than two decades, Neat Acoustics has been exploring isobaric loading for some years. The Ultimatum MFS is very much the inspiration for this new, simpler and much cheaper Momentum 3i. It's still costly for a standmount at £1,745 per pair, but does include isobaric loading within a high-quality wood-veneered enclosure.
The term isobaric requires some explanation. Here it involves mounting a second bass/mid driver on a separate baffle inside the enclosure, separated by a cavity from the visible driver on the front and operating in acoustic series and electrical parallel. Exactly how this operates is not entirely clear.
Simplistically, it effectively doubles both the moving mass of the diaphragm (lowering the fundamental resonance of the combination) and its electromotive 'shove' and should, therefore, deliver good extension from a relatively compact enclosure. At the same time, the internal driver should act as a 'shield' between the effects of the enclosure and the visible driver on the front.
The Momentum 3i is an average sized standmount with an internal volume of around 14 litres. The enclosure is nicely done in a choice of four matt-finished real wood veneers. Our example came in oak, but maple, cherry or rosenut options are also available.
Despite the extra internal main driver, this is essentially a two-way design. The main drivers are Neat's familiar high-class 168mm units with a 120mm diameter doped and flared paper cone. The tweeter is Neat's own concave 25mm alloy dome device, in place of the no longer available Focal tweeters the company used to use. The drivers are nicely rebated, while a grille is an optional extra.
As the Lab Report opposite indicates, this speaker should certainly be positioned well clear of walls to avoid unwanted mid-bass excess. Even without wall reinforcement, the bass end is quite full and the top end is also quite strong, bringing a slight 'loudness contour' character to the proceedings.
Although the speaker remains fundamentally neutral, this factor also adds a little extra sense of weight and scale. This is actually quite welcome when playing the system quietly, though it can become a little unruly when the volume is turned up high. Indeed, this standmount often sounds more like a floorstander, in terms of the weight it delivers, yet it also has the agility and lightness of touch of a high-quality standmount.
Perhaps its biggest plus point lies in the low coloration and freedom from boxiness that's clearly well ahead of the pack and very likely associated with the isobaric configuration. The strong treble probably contributes to the superior detail and fine vocal intelligibility, though the overall impression is quite restrained and understated and the midband could perhaps be a little more expressive.
However, the overall dynamic range is very wide, images are precise and the whole thing sounds very clean and coherent, as well as rather larger than its physical dimensions lead one to expect.