SA-6.5CS v.3

The Sundown Audio SA-6.5CS v.3-6.5 inch front component set features a specially developed mid-bass driver. The mid-bass driver is built on a high-quality cast aluminum basket, while many speakers in this category use cheaper stamped steel frames.

The cone is made from high-quality carbon fiber fabric. The dust cap is also made from the same material as the diaphragm. The surround is made from a very compliant rubber, which helps to tame any remaining edge resonances within the diaphragm. For all midrange drivers, the diaphragm, surround, and dust cap are crucial for sound quality. After extensive testing, Sundown Audio chose exactly this combination for the v3 iteration of the SA component set.

The motor was internally FEA-optimized to increase linear excursion and offers a full 6 mm linear excursion in one direction thanks to a carefully designed motor and an extended pole piece. In developing the SA midrange driver with a vented magnet gap and vented voice coil collar, we also carefully considered thermal performance. The power rating of 60 watts per side for the SA midrange driver was derived from an 8-hour pink noise test (full bandwidth down to 20 Hz) – so if you push the lower range, this number is very conservative. Most customers use RMS amplifiers with 100+ watts for the SA devices.

The tweeter of the SA series had to match the smooth sound of the midrange driver, so we chose a silk dome. We tested numerous versions, optimized the gap, dome material, tested different lenses, various chamber damping materials, and so on until we arrived at the final design. As the frequency response graph proves, the result is an incredibly smooth-sounding tweeter. Don’t be fooled by the simple housing – we’ve all learned not to judge a book by its cover, and you’ll find this tweeter performs as well as or better than many fancier counterparts. We stuck to the Sundown mentality of not spending money unless it improves performance.

The crossover also looks relatively simple at first glance, but it perfectly fulfills its task. It is a 24 dB network centered at 3800 Hz, with high-quality air coils and Mylar capacitors. It also features a built-in tweeter protection circuit to prevent premature failure due to clipping.

Technical specifications

• 6.5-inch component speaker system
• Power 250 watts RMS
• Impedance 4 ohms
• Silk dome tweeter
• Aluminum tweeter housing
• Aluminum frame housing
• Magnet ID shorting ring (midrange driver)
• Carbon fiber cone
• Rubber surround
• 24dB/octave crossover
• Adjustable tweeter level (-3, 0, +3)
• Mounting depth: 7.1 cm
• Cutout: 14.2 cm