Creating a system you love shouldn't be difficult. The Acoustic Frontiers blog is here to help.
These units are great sounding speaker correction, room correction and digital crossover processors. They essentially replace your pre-amp and DAC. You feed them an analog or digital signal (or signals if you have multiple sources), then the DEQX corrects speaker and room issues through powerful DSP algorithms. Implementing it in this way is called DEQX-Inline, and you can review this PDF to learn more.
You can also go active with the DEQX processors, whereby you feed each 'way' of your speaker a separate filtered signal. This digital crossover replaces the passive crossover in your speakers and improves sound quality since each driver is now direct coupled to a separate amplifier channel. This implementation is called DEQX-XO - see here for more.
The new units have 24/192 capable digital inputs for proper integration with modern music servers and feature internal 32 bit Burr Brown PCM1795 DACs. The whole main PCB has been completely redesigned to improve performance. The HDP-4 also comes as standard with balanced and digital outputs as well as a pass through ouput which makes using the HDP-4 for a four way speaker system much easier. You can use a HDP-4 for the tweeter, midrange and woofer and then use a cheaper DSP - such as a miniDSP - for one or multiple subwoofers.
Hope that gives you a quick overview of the new units...and as always, if you have any questions please contact us.
Nyal Mellor, Founder, Acoustic Frontiers