DALI Speakers Launches New Flagship V-16 F 16" Subwoofer

DALI V-16 F Introduction

While the loudspeaker manufacturer DALI is not best known for their subwoofers, they do have a handful of subs available that look fairly typical and reasonably designed. Their existing offerings look competent, but, on the surface, they don’t do anything that sets those products apart from competing manufacturers. That is about to change with the launch of their new flagship subwoofer, the V-16 F. The V-16 F looks to be a serious engineering project that pushes the state-of-the-art forward in subwoofer design with a slew of new technologies. It’s a large subwoofer with a not-insignificant price tag intended for large rooms or very high-output and deep bass applications.

DALI V-16 F 16" Driver Design Details

Let’s begin the discussion of the V-16 F’s technologies by starting with the driver’s remarkable suspension system. The driver uses two spiders that have a ‘mirrored’ mounting where one spider is mounted inversely to the other. The advantage of this is that whatever nonlinear movement in one direction that one spider alone would have would be offset by the other. That should do a lot towards eliminating any even-order harmonic distortion generated by the spider. Dual spiders also strengthen the hold that the spider system has on the former, and this will help to restrain the former’s movement in a single plane of travel. That means the former will be kept centered under higher stress conditions won’t be as easy to lose alignment in the tight space of the magnetic gap.

Mirrored spiders are a neat touch, but it isn’t something that has never been done before. An innovation of the V-16 F suspension that is unique is the use of the Constant Surface Surround (CSS) Technology in a large subwoofer driver. We have seen CSS in bass drivers for loudspeakers, but not a massive subwoofer driver. CSS was developed by Purifi Audio and is easily distinguished by the irregular patterns formed by the shape of the surround. It isn’t so surprising to see CSS technologies deployed by DALI, since DALI was founded by Peter Lyngdorf, who also co-founded Purifi Audio. What is neat about the shape of the surround is that it is symmetric at the resting position. What that means is that it will behave the same way when pushing out as well as moving inwards. When we look at a typical half-roll surround, there is no geometric symmetry at all because one side is concave and the other is convex. That means that the tension exerted on the driver will not be the same for both directions of travel. This asymmetry leads to even-order harmonic distortions as one part of the cycle of the sound wave becomes deformed.

Another interesting aspect of the CSS technology is that it keeps the radiating surface area more uniform for both inward and outward directions of travel. When a typical half-roll surround moves outward, the tension on the surround stretches out upward, thereby losing the contribution it made toward moving air as a part of the radiating surface area. Conversely, when the cone moves inward, the surround becomes a much larger part of the radiating surface area since it then becomes more congruent with the geometry of the cone. The CSS Technology contributes about the same amount of radiating surface regardless of its position in the cone’s movement. Again, this helps the driver to remain more linear across a wide range of amplitudes than conventional designs.

The voice coil used is a 4-layer copper-clad aluminum wind with a 3.5” diameter and a 1.7” length. The former is made from glass fibre instead of the usual aluminum. The advantage of aluminum is that it can act as a heatsink and reradiate heat more quickly, but its disadvantage is that it is paramagnetic and can have undesired effects on the intended magnetic field. While glass-fibre doesn’t have the thermal advantages of aluminum, it doesn’t affect the magnetic field. There are lots of other ways to deal with heat dispersion, so I consider this a worthwhile trade-off. The magnet is a triple-decker of ferrite slugs that add up to a 2.4” thick stack with a 7.9” diameter. That should add up to a lot of magnetic flux, and DALI claims it is the most powerful ferrite magnet that they have ever used. This motor system allows the driver to have a healthy 16mm of one-way linear excursion and 35mm of one-way maximum mechanical excursion; that is a lot of air movement when considering the size of the cone.

The cone has a 16” diameter and is made from aluminum. One might think such a large driver would be good for deep frequencies only, but DALI claims that its response extends out past 1kHz. One reason for this is the use of shorting rings. DALI has mounted two aluminum shorting rings around the pole piece, which helps to reduce inductance. The V-16 F driver has a lot of coil that is bound to cause a lot of inductance, and inductance raises distortion as well as reduces the frequency bandwidth. Shorting rings, aka Faraday Rings, do a lot to fight inductance, although they make it more difficult to magnetize the ferrite of loudspeaker motors, especially such a large motor as used in the V-16 F. 

DALI V-16 F Amplifier Design Details

This beefy driver is powered by a 1,500-watt RMS class-D amplifier. Pre-amplification is handled by digital signal processing with some interesting features that I have not seen on other subs. One is a single-band parametric equalizer that DALI terms the ‘Room Mode Attenuation.’ While a single band of parametric equalization is nothing to get excited about, DALI has made it very easy to use for finding a applying it in eliminating a primary mode peak by pairing it with a tone generator. This helps users to find and eliminate a mode on the fly. That might not be of interest to an advanced user, but it can be very useful for someone who is less technically inclined and is only interested in using the sub for a simpler audio system.

Another interesting feature is the claimed ability to flatten out group delay. Avid readers of Audioholics subwoofer reviews will know group delay as stored energy that is frequency-dependent. It is unavoidable depending on the design of the subwoofer, and almost all subwoofers will have some level of group delay. The V-16 F has a control called ‘Constant Group Delay’ which is supposed to flatten out group delay. It seems to work by adding a frequency-specific delay across the sub’s bandwidth up to 40ms, so lower-latency frequencies have the same delay as higher-latency frequencies. It does depend on the user having a processor that can add delay to the speakers so that subs are synchronized with the rest of the system. In theory, it should work to eliminate any group delay below 40Hz in a properly set-up system. These features, plus a bunch of others, are accessed through a neat inset control panel with a small screen on the top front of the sub.

DALI V-16 F Cabinet Design Details

The construction of the subwoofer cabinet looks pretty heavy-duty. Side panels are 1” thick, and the front baffle is 2” thick. There are two window braces shoring up the sub at third-length points. One of the braces also supports the driver motor. All of this cabinetry plus the hefty driver adds up to a 117 lbs weight. One unusual feature of the sub is that it has four front-firing ports mounted at the enclosure corners. Normally, that would be a cause for concern; a bunch of smaller ports is more likely to produce port turbulence than a single large port, since there is more port surface area versus air volume in the port. However, DALI has designed specially shaped ports that should maintain laminar flow and discourage turbulence. It gives the V-16 F an interesting and unusual appearance. The port tuning is set to 18Hz, which should enable the V-16 F to easily dig into infrasonic frequencies in-room.

The DALI V-16 F is set to release in July with pricing at £4499 / €4999. USA pricing has not been announced yet, but I expect it will be around $6k. That is a lot of scratch, but the V-16 F is a lot of subwoofer. It’s good to see a traditional European loudspeaker manufacturer start to take subwoofers seriously. We are hoping to experience one for ourselves on this side of the Atlantic, and if we do, we will certainly bring you a full report of our experiences, so stay tuned to Audioholics to learn more about this new beast from DALI.

Unless otherwise indicated, this is a preview article for the featured product. A formal review may or may not follow in the future.