Is DEQX a game changer?

Yes, the software, user manual etc are available to download from the DEQX site (you will need to ask by email: [email protected] for the latest login & password to do so). 

Thanks! That's great news. I've been in contact with Alan Langford. I'll ask him.

I bought my DEQX PreMate+ back in December 2017, and finally got it calibrated on Thursday so I’m now utilizing its digital crossover and room correction functions. Here is a rundown of the setup process, and my impressions. After living with the DEQX as just a DAC-pre for over four months, I can say I’m quite pleased with how the DSP has improved the sound (more on that later).

I was too intimidated by the calibration software to attempt it myself so I booked a session with a reputable “DEQXpert” aka dealer, named Larry Owens, based in Colorado. It took about 3.5 hours from start to finish. While it took longer than the 2-3 hours he estimated, I was quite impressed with Larry’s knowledge and adeptness with the software.

I expected that we’d start by taking near field anechoic measurements of the speakers, but my DEQXpert, Larry Owens felt that might not be necessary. We started by placing the mic at the listening position and based on the measurements, he felt that would be sufficient for us to implement a crossover for the sub/mains and correct the in-room response. I’m not sure exactly why we skipped the near field measurements because much has been made about that element to distinguish DEQX from other room correction products that don’t do speaker correction. I can say that if we’d done those measurements, it probably would have taken twice as long.

Before ever seeing any measurements, I expected a few things: (1) that my subwoofer was set a bit louder than the speakers, (2) that I had some nonlinearities in the bass, particularly due to some dips below 80 hertz, (3) that my left channel near the wall was less accurate due to boundary effect, and (4) that the high frequencies were slightly emphasized in-room. Turns out all of that was true except for the fourth point. The highs were fairly well behaved already.

The speakers (mostly left channel) had a dip around 60-70hz and the sub had a dip around 80-90 hz so by setting a digital crossover at 78hz, voila, both dips were avoided! From there, Larry made a bunch of very precise corrections in both the timing and frequency domain that made things look progressively more beautiful as he went along.

With just a couple hours of listening under my belt, I can say the system's frequency response is noticeably flatter. The sound is more precise; less vague. The bass is less room shaking than before simply because it was set too high, but now it’s definitely tighter and more articulate. It makes it easier to follow a bass guitar line and distinguish pitch (less monotone bass). I also feel like the bass in more consistent throughout my room, which I didn’t expect and can’t quite explain.

 

My stereo presentation is also noticeably improved after Larry corrected each speaker to more closely match each other. Before the calibration, I perceived my Revel F208 tweeters as a bit too bright so I used the switch on the speakers to turn them down .5-1dB. Larry pointed to a slight peak at a narrow but critical region in the upper mid treble that he suspected might be the culprit. He used parametric eq to flatten that out and I think that solved it. Much better to address that one narrow problem than turn down everything above 3k with that tweeter knob on the speakers. The highs sound more accurate now. Not too prominent nor too recessed.

I will live with this for a while and report back to Larry if any additional tweaking is needed. He’s been a joy to work with.

 

Blang11, thanks for providing the thorough and extremely well composed report.  Glad it worked out so well.  Enjoy!

Best regards,
-- Al

@almarg : Hi Al.  I,m taking steps to acquire a PreMATE Plus at the first of the year and am selling some seldom used gear, to help offset the cost.  I have a subjective question, concerning the connection of my Theta Miles CD player.  I am currently using the Theta through its analog balanced outs, going into my Aesthetix Signature linestage.  I decided to run the Theta through my Casablanca 3 and must admit, it sounded a little clearer, than the Aesthetix.  I have a Kora Hermès II, also presently not in the chain, that I thought I may use in front of the Deqx unit.  Do you have an opinion on which would give me the better sound?  Theta straight to the Deqx, or Theta + Kora+ Deqx?  Without the Miles own dac, I would be using a digital cable apron 20’ long, as I’m already using a better quality set of XLR’s to my linestage.  Also,I have the Casablanca up for sale and couldn’t find a fair true price, to ask for the unit.  I simply checked the blue book and compared it to other CB3’s on the market.  I’m not trying to gouge anyone-just not sure about the asking price.  One more question-I’m planning on getting the M23 mic, but can get it for about half the cost Larry is asking.  Do you know of anyone who has done this, then purchased the mic files?  One last comment.  For my two JL F113’s, I’m using a separate preamp coming out of the linestage tape out.  This gives me total separate volume control, over my subs.  My Wilson’s have very deep bass and I use the separate sub volume control, to offset any lacking in bass, depending on the source’s bass output.  It’s a setup that has worked very well, in tailoring the bass to fit the source.
Thanks in advance,
Steve