"For audiophile sound quality, and value, the HDP — Express definitely deserves an Audiophilia star".

DEQX HDP-Express Pre-amplifier / Processor.

I encourage the reader to try this out. First, use the DEQX to correct the frequency response and phase anomalies that are inherent in all speakers. The DEQX will realign the timing throughout the frequency range. Then, use the room correction feature. You will find the improvement is amazing. But, if you have speakers that can be bi-amplified, or tri-amplified, or if you are willing to modify them to use the DEQX electronic crossover, you will never want to go back. The difference in clarity, detail and dimensionality will astonish you. Also, you will be surprised in the total lack of digital artifacts in the sound. It is smooth and analog clean. …read more

Michael Levy, Audiophilla

"Give that man an Audiophilia Star Component Award".

DEQX HDP-3 Pre-amplifier / Processor.

The bottom line is that Kim Ryrie has improved an already outstanding product and created one that blurs the line between digital and analogue. Detail without edginess, unbridled musicality, transparent, dynamic and a level of involvement with the performance that is simply stunning. I’ve tried to describe, using some of our audiophile terminology, what one hears with the HDP-3 processor in your system and words don’t do it justice. It behooves you to try one — once in your system, you won’t let go. Removing it from your system will return you to a duller, two dimensional stereo that’s lost its magic. My system would be lost without it. …read more

Martin Appel, Audiophilia


“The Legend Acoustics Tikandis with the DEQX HDP-3 are a very special combination”

I have never heard better sound in my listening room. The tonal accuracy, frequency extension, and most impressively the ability to pull detail out of recordings was nothing short of astonishing.… If you already have your own speakers, the HDP-3 processor can dramatically improve the performance of your loudspeakers.” …read more

Dr Chris Groppi, Home Theater Hifi

“Chris Martens' Best of RMAF 2009”
Showing the way of the future, the Legend Tikandi loudspeaker features an all-digital DEQX crossover/DSP box providing preamp, crossover, driver correction, and room/speaker EQ/voicing control functions.” …read more

Chris Martens, The Absolute Sound

“Some of the best DSP room correction I have heard…excellent everywhere in the room”
At last year’s T.H.E. show I suddenly heard someone playing a live drum set in one of the surrounding rooms. Having played the drums for 40 years I’m familiar with the sound of a live kit. Turns out it was a pair of Acoustic Zen Maestro speakers ($36,000)…The amplifiers were being fed by the DEQX HDP3 room processor. With its included measuring microphone, the HDP3 first checks the anechoic phase and amplitude response of the speakers…"…read more

Adam Goldfine, Positive Feedback Online

"What I heard was truly amazing…"

"What I heard was truly amazing, jaw dropping, illuminating, eye opening, ear opening… well, you get the picture… Height, width and depth were all bettered. Instrumental layering became clearer, as well as their separation. Air around instruments took on a more vibrant quality and at the same time the instruments themselves took on solidity and three dimensionality that was beguiling… Detail levels increased across the entire musical spectrum without adding any clinical edge to the sound. Quite the contrary, an analogue-like smoothness and liquidity pervaded what I heard…

The DEQX shows us that by removing speaker inaccuracies and distortions our listening window becomes clearer and more transparent then ever." …read more
Martin Appel, Audiophilia

"Listening to my own playing…was like looking in a mirror, sonically speaking…"

"In the world of conventional standalone speaker designs, DSP speakers from Sonicweld and Wasatch were using the DEQX digital box to good advantage. Both systems used crossover slopes much steeper than usual, taking advantage of digital filters with steep slopes but linear phase. Both speakers have very flat frequency response and excellent phase behavior. They also have very wide dispersion patterns, which implies some considerable dependence of the sound on the room characteristics (above the bass, where DEQX room correction was being used). As it happened, the Sonicweld was in a large, heavily curtained room. It sounded very smooth all the way up, and indeed offered quite stunning performance. Neil Gader called it "lovely" and it seems an apt word. I had the sense of hearing very exactly what was on the recordings. Listening to my own playing (from REG plays Dvorak, available on regonaudio.com) was like looking in a mirror, sonically speaking, so exactly did it sound like my own instrument."
Robert E. Greene, The Absolute Sound

Best Sound at CES 2006

"Sonicweld takes a systems approach with its active loudspeakers. Not inexpensive at $49,000– $64,000 (depending on subwoofers), the system comes complete with triple ICEpower modules for each quasi-line-array satellite speaker, a Subpulse bass module, and the DEQX PDC (preamp-style functions and digital crossover and room correction).Sonicweld's trademark CNC aluminum construction throughout is a mindblower.
Neil Gader, The Absolute Sound

"The best thing to come down the pike in a long time..."

“As the designer...switched from the passive factory crossover to the active DEQX crossover, I was amazed." …read more

Kalman Rubinson, Stereophile

"I agree with Kal Rubinson—the Xd system is the best thing to come down the pike in a long time."
…read more

John Atkinson, Stereophile

"Well-defined soundstage with remarkable accuracy and unmistakable depth and dimension"

In Home Theater Magazine, reviewer Chris Lewis gives the DEQX Calibrated™ NHT Xd loudspeaker
system an overall rating of 95 and says: “My eyes saw small, unobtrusive, and rather pleasing-looking satellites and relatively compact subs. But my ears heard a full, well-defined soundstage with remarkable accuracy and unmistakable depth and dimension.”

Chris Lewis, Home Theater Magazine

"Smoothest, flattest, most extended frequency response of any loudspeaker system…"

"…where the sound quality of this system is concerned there are no limits…NHT's XdS system returned the smoothest, flattest, most extended frequency response of any loudspeaker system Australian Hi-Fi Test Laboratories has ever tested." …read more (pdf)

Greg Borrowman, Australian Hi-Fi Magazine

"A tremendous development tool for speaker engineers…"

"Although the DEQX PDC-2.6P is really designed as a consumer-level product, I believe it is also a tremendous development tool for speaker engineers…I've reviewed alot of software over the years for Voice Coil, and the DEQX software ranks among the very best…You go from initializing the software to a complete crossover design so fast, you'll be wondering whether you did something wrong, but you didn't.Since the process is so straightforward, the actual design time is fairly short." …read more (pdf)
Vance Dickson, Voicecoil Magazine

"Heads and shoulders above the next competitor…"

"…the Encore categorically eschews non-linear, phase-challenged, passive crossovers. Instead, it relies on phase-correct, active, digital crossovers with ultra-steep 96dB/octave slopes……They find its DSP board (embedded with over one million lines of proprietary code) to be heads and shoulders above the next competitor, i.e. of true, uncontested and unequaled reference caliber." …read more
Srajan Ebaen, 6moons.com

"A time machine in a one-rack-space box…"

Reviewer Edgar Kramer sees and hears the future of audio with the PDC-2.6P (he calls it "…a time machine in a one-rack-space box…") and is so impressed that he gives it a 6moons
Blue Moon Award …read more
Edkar Kramer, 6moons

"Stephen Miller "likes what he sees…and hears"

CEDIA's Stephen Miller tries out a PDC-2.6 Digital Correction Processor and likes what he sees—
and hears …read more (pdf)

Stephen Miller, CEDIA
Reproduced with kind permission from Connection Magazines, publishers of Connected Home Solutions.

"Imaging and soundstaging that are just jaw-droppingly great…"

"Best Loudspeaker Under $6000: NHT Xd. The Xd...uses advanced DSP filters (developed by DEQX) to achieve flat frequency response and exceptionally good impulse and phase response characteristics…Not only does the Xd sound wonderfully uncolored (as its fine measurements would suggest), but it offers gobs of resolution and finesse, plus imaging and soundstaging that are just jaw-droppingly great..."
Chris Martens, AVguide Monthly

"Ranks among the very best…"

"...I believe it is also a tremendous development tool for speaker engineers…I've reviewed alot of software over the years for Voice Coil, and the DEQX software ranks among the very best…You go from initializing the software to a complete crossover design so fast, you'll be wondering whether you did something wrong, but you didn't…Since the process is so straightforward, the actual design time is fairly short…"
Vance Dickason, Editor, Voice Coil Magazine

"Incredibly flexible and powerful…"

"The DEQX system was incredibly flexible and powerful in terms of EQ and room correction. A proprietary set of NHT speakers that are designed to work with their system sounded uniquely good."Jerry Del Colliano, Editor, Audiorevolution.com

"I simply have not heard another speaker that…competes with these on accuracy of tonality"

David Rich of $ensible Sound previews the new NHT Xd speaker, the world's first purpose-designed
DEQX Calibrated™ system: "In my opinion, the only thing as tonally neutral as these speakers is the sound heard from the world's best head phones. I simply have not heard another speaker that I can say competes with these on accuracy of tonality…With my CDR compilations I was able to check out 15 of my most revealing test tracks and I will tell you I was very impressed…What do we conclude from all this? The days of the passive crossover are as numbered as black and white TV was when color was introduced.Purchase a $10,000 speaker with passive crossover today and see its value drop to three figures on eBay in three years.
"David Rich, $ensible Sound

"Miracle product of the decade without a doubt"

"Miracle product of the decade without a doubt. It's cheap, it works, you get more than you're paying
for. As a Preamp alone it's worth ten times more than what you pay. The EQ is essentially free.
"Spatial Research, Australia

"State-of-the-art bar none…"

"…Enter the programmers from down under. I’ve now heard from numerous highly placed sources in the audio engineering world that their DSP process must be considered the current state-of-the-art bar none...The great opportunity which currently presents itself to the loudspeaker market is "infinite slope"
digital crossovers and phase, time and frequency correction.The advantages inherent in the DEQX solution mandate a close investigation by any loudspeaker engineer who is truly serious about perfecting the art.
" Srajan Ebaen, Editor, www.6moons.com

“Proof of concept in a hotel room' award

"…the company's…DSP correction system noticeably improved the midrange tonality and imaging we were hearing each time it was switched into the circuit…This prompted us to give the company the 'proof of concept in a hotel room' award for that year.
"Jon Iverson, Editor, Stereophile Online Magazine

"I believe your computation system will be easier and do a better job"

"What attracts me is the 'automatic' function of the tuning…also the steepness of the filters. I have been using LMS…in an iterative and drawn out fashion. I will be pleased to give up this practice.I believe your computation system will be easier and do a better job."
Ken Goerres, Professional Audio/Acoustic Consultant

"Sound(s) very expensive"

"Chris Holder plugs in a box that makes his monitors sound very expensive." …read more (pdf)
Chris Holder, Audio Technology

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