The speaker cabinets, drivers, bass port designs, amplifiers, and passive crossovers are all tuned together for the HD6. This, in turn, helps make for a more efficient system that requires less power than passive speakers and a separate integrated amplifier or similar A/V components. Audioengine builds all this into the left speaker cabinet to make it easy to connect your smartphone, tablet, computer, display, network player, or any other audio product.

Audioengine has taken features from the B1 aptX HD Bluetooth Receiver and the D1 24-bit DAC, and combined some of this circuitry inside the HD6.

The Bluetooth built into the HD6 powered speakers features aptX HD coding, which is a Bluetooth audio codec designed to help provide enhanced sound quality. And even if your phone or tablet doesn't have aptX HD, the HD6 Bluetooth solution is backwards-compatible with SBC and AAC codecs, so you can wirelessly stream music from any Bluetooth-enabled device and still enjoy all your music.

The HD6 offers a Bluetooth solution that has up to a 100' range for multi-room use, with virtually no degradation in audio quality.

The HD6 Bluetooth receiver and optical input both utilize the AKM AK4396A DAC, which is designed to provide low noise and high fidelity. The optical input configures the DAC as a bit-perfect 24-bit DAC, which will process sample rates up to 192 kHz natively. For Bluetooth, the AK4396A is used as an upsampling DAC and will pad all bit depths to 24-bits, achieving a higher signal-to-noise ratio and lower noise floor. Due to the high signal-to-noise specs of the AK4396A, the fact that digital signal is upsampled to 24-bits, and the added benefit of onboard triple redundancy power source conversion and filtering, the HD6 Bluetooth implementation is engineered to present impressive low noise and low distortion characteristics.

The amplifiers in the HD6 are located in the left speaker and feature class A/B analog monoblock design. This is designed to provide high-quality audio and greater flexibility, and all the circuit boards for the power and preamp sections are vertically mounted for augmented mechanical shock protection.

Audioengine uses ferrofluid-cooled silk dome tweeters with neodymium magnets. Silk tweeters are engineered to hold up well under high power, and the edge-driven design helps provide a smooth response. The woofers are Kevlar woven glass aramid composite with rubber surrounds. The strength of Kevlar means the woofer retains its shape when being driven at high levels. The HD6 woofers are housed in cast aluminum frames, which help provide high rigidity and increased heat dispersion.

Audioengine uses gapless-core toroidal transformers, which have a tighter radiated magnetic field, translating to lower noise. They are lighter than standard "EI" transformers, and also generate less heat.

The HD6 includes detachable grilles that are held in place with hidden neodymium magnets for a clean look.