Creating a system you love shouldn't be difficult. The Acoustic Frontiers blog is here to help.
DEQX, a company from Australia reknowned for their pioneering use of DSP loudspeaker correction, have released a new product called the HDP-Express.
Acoustic Frontiers is proud to be selling the DEQX HDP-Express and DEQX HDP-3 from our ecommerce store. HDP-Express and DEQX HDP-3 are now discontinued and replaced with the HDP-4, HDP-Express II and Mate, see the DEQX page on our website.
The HDP-Express ($1950) provides exactly the same digital room correction, digital loudspeaker correction and digital crossover functionality as the twice-as-expensive ($3995) HDP-3. The concessions that have been made are to replace the linear power supply with a switching unit and to implement a lower cost volume control system.
The DEQX HDP-3 and HDP-Express meet all of our criteria for a room correction product (see the table below for more details). In addition they provide significant opportunities to further improve your system through use of digital crossover and digital loudspeaker correction.
Acoustic Frontiers is an authorized dealer for DEQX. HDP-Express and DEQX HDP-3 are now discontinued and replaced with the HDP-4, HDP-Express II and Mate. If you have any questions on this awesome unit please get in touch!
Note that for home theater TWO HDP units in a special 'master/slave' mode must be used to provide correction of the LCR and surround loudspeakers. The DEQX units would be connected between pre-processor and power amplifier.
In case you missed the detailed explanation of the functional criteria that I am reviewing room correction products against please see here and here. If you didn't read the detailed and comprehensive introduction to room correction, see this article.
The functional criteria that we reviewed the DEQX products against have been shortened to fit into the table. Here is the interpretive legend:
If you didn't read the detailed and comprehensive introduction to room correction, see this article.
Manufacturer |
Model |
Choose Freq |
Choose Target |
No A/D or D/A |
Auto Measure |
DEQX |
Yes |
Yes |
Yes |
Yes |
I e-mailed Alan Langford from DEQX to get a bit more detail on the differences between the HDP-3 and the HDP-Express. He provided this table and said:
The linear power supply and importantly the post DAC 6 channel post analog volume control has been removed. We have also removed the front panel control buttons and simplified both the chassis and electronics to reduce manufacturing costs. For high end 2 channel audio I would still recommend the HDP-3. Where the HDP-Express works well is with home theater and reduces the cost of implementation where the volume is always controller by the AV processors offering only analog outputs (Dolby & DTS have no post decoding digital signal) In this case the DEQX would always be set to maximum output level so by-passing any effect of using digital volume in the DEQX.
Nyal Mellor, Founder, Acoustic Frontiers
Nyal Mellor
Author