The HDX line of subwoofers builds upon the HDC line, with design changes geared toward recent shifts in source material and the mainstream frequency tuning of our customer’s cars. All elements of the HDC subs were scrutinized for better performance at lower frequencies. The resulting HDX line is more efficient, plays lower, sounds better and sets a new bar for performance and value.
Lower frequency use requires an increase in excursion. We started with a new cast basket which allows larger diameter spiders to be used, provided more excursion room for both the cone and spider travel while providing open airflow path for increased heat dissipation.
New spiders were tooled to take advantage of the increased suspension travel, the number of rolls increased along with the roll heights. This extra material in the spiders increases the freedom of movement, lowering the Fs but allowing a high layer count for long term durability.
The surround profile was increased in height which, along with the new spider profiles, reduces material stress while increasing excursion ability. Cone area and moving mass remain virtually the same as opposed to inner-tube surrounds popping up here and there.
The extra throw places more demand on cone strength, the HDX now use a cone pulp reinforced with fiberglass strands and formed in a non-press method to increase the cross section area of the cone walls. This increases the rigidity of the cone without adding extra mass. The material cost and forming time go up, but the overall efficiency of the subwoofer is increased.
The voice coils in the new HDX have been strengthened in every way. The aluminum formers are thicker and black anodized to increase thermal transfer from the coil wire. USA wire and adhesives are used to increase the thermal working range of the coil.
This HDX overhaul increases the low frequency pressure that can be tuned into a system without sacrificing the impacts and brutal power that SQ subs have been known for. The .X subs give you more freedom to explore design choices with high efficiency, making the most of amplifier power and electrical resources.
NOTE – Rated power handling is after break-in period.