Is DEQX a game changer?

Congratulations on your purchase Almarg - I think it's very good to do the first run through of the measurement and calibration process in situ. I dragged the system outdoors when I first did this but realised a few days later that I should have done a few things differently so had to repeat it again. You will learn a lot during the first few weeks and it does take time to understand everything fully

I originally made a number of indoor measurements & the closest I managed to the result outdoor was by lifting the speakers onto a small table in the centre of the room so the driver set was roughly equidistant between floor and ceiling with the mic about 3' away and centred between the drivers but slightly higher towards the tweeter (which will be in line with your head during normal listening). Place the speaker at the extreme front edge of the table surface, even better if you have something the same width as your speaker to minimise reflections.

Place as much soft material as is practical on the floor between speakers and mic, ie a mattress if possible or several sun lounger cushions etc. You will not completely kill the floor reflections and there will be some from the ceiling but it does help

The measurement should show a point where reflections become apparent (very clear and distant outdoors but much less so in a room) and where the truncation can be made. For me, no matter how good an indoor measurement, the resulting calibration never managed to lose a slightly unnatural or hollow sound. Measurements outdoors, although a massive PITA, is so much more accurate if everything is done properly. Patience really pays off with DEQX - if you are inquisitive, make several attempts, take advice from Nyal and with experimentation it will be worth it in the end. You have the flagship processor so make the most of it and good luck!

Bruce previously sent me his files and Larry windowed at 24ms and 98% smoothing. My own outdoor measurements are windowed at 26ms & 0% smoothing because measuring 'anechoically', the plots are clear and have almost no reflections or impulses other than the speaker itself - it's an almost flat line until a clear and tiny reflection at 26.2ms which repeats every 3ms until fading away at 36ms

However the windowing I quote is based on reflections made by Bruces' setup and will be different for yours. To be safe, I would suggest you try to look for a clear smoothish area after the main impulse and before the first obvious reflection. However, that may be difficult with a somewhat confused indoor measurement

Bruce previously sent me his files and Larry windowed at 24ms and 98% smoothing. My own outdoor measurements are windowed at 26ms & 0% smoothing because measuring 'anechoically', the plots are clear and have almost no reflections or impulses other than the speaker itself - it's an almost flat line until a clear and tiny reflection at 26.2ms which repeats every 3ms until fading away at 36ms

However the windowing I quote is based on reflections made by Bruces' setup and will be different for yours. To be safe, I would suggest you try to look for a clear smoothish area after the main impulse and before the first obvious reflection. However, that may be difficult with a somewhat confused indoor measurement

Apologies for the delay in response here guys as I am in Europe and there is obviously a time difference

Answering the question about windowing - an indoor measurement is not as clear as one taken anechoically and those sent by Bruce are rather like that although it is not bad by any means. My own measurements are crystal clear, a strong main impulse followed by a virtually flat line with four 'tiny' fading reflections. What you are supposed to do is window just before the first apparent reflection (26ms vs 26.2ms in my case). Larry has windowed at 24ms although I see a fairly strong reflection at 19.6ms so this will be included in the calibration

Regarding room correction - I may be lucky in that my music room has solid walls and floor and I am able to keep speakers and chair well away from walls using the so called 'golden formula'. Using two subs has also helped so that I need minimal room equalisation: max - 1.5dB at just 33.4hz & 36.7hz and further very slight equalisation below 219hz - bass is very tight, dynamic and uncoloured (much less eq than Larry has used in Bruces' room which is in a range of -3.7 to +4.1dB between 116hz and 1469hz)

As for time alignment - I originally used DEQXperts from the manufacturers in Australia and also the Netherlands. They taught me a lot but I was never told to use unequal timing for main speakers which is what Larry has done (6.60ms LH main speaker, 6.68ms RH). Maybe it's something to do with Bruces' room or he is seated off centre? In any case time alignment needs to be checked by ear and I align the matched peaks of the subs to the first rise of the main speakers rather than the first impulse peak as Larry has done. I have listened to both arrangements and in my setup aligning to the rise rather than peak gives a natural and seamless bass response where I can clearly hear each instrument individually and especially the realistic 'growl' of a bass guitar from within the lowest frequencies

And for Subs - yes it is good that they take over the lower frequencies so that all amps and driver sets have a narrower band to work with (ie cleaner, clearer), in my case at 100hz with a 48dB Linkwitz-Riley crossover. Larry has used 120hz, 24dB and Butterworth so this may be related to the combination of speakers and subs that Bruce uses. I found that my subs (Miller & Kreisel plus B&W) sound slightly unnatural if I crossover above 100hz and at below this, my Open Baffles lose some attack

I must admit that I spent many months experimenting, taking advice, re calibrating and listening before I arrived at the optimum for my system so it all depends on how much time each of you can put into this. A DEQXpert (or another user like me) in a remote location can advise but only YOU know what you are listening to

With that in mind, I will mail Bruce and look at his latest measurements as suggested. It's a shame that this forum does not permit embedded illustrations as I could explain this so much better by screenshots of our two setups

Here to help if I can....

This reply is to Bruces' questions - From your measurements I would say you are already using very good speakers as the response is better than I managed to achieve in-room with my original Shahinians. I guess you used quite a lot of sound absorbtion material

Investing in time aligned speakers is not really the issue as the DEQX algorythm has already time aligned all frequencies that the mic picked up from your exiting pair (including the reflections of course!)

I think the 'heavy hand' probably results from a combination of:

- In-room measurement reflections which are included in the subsequent calibration
- A poor room or placement
- Your inexperience with the room equalisation and reliance on either the auto-eq or Larry trying to set this, based on your comments over the 'phone

I sent you a couple of emails with screenshots & a suggestion to experiment by starting with less room equalisation based on the lower frequency peaks you can see on the software, playing music which tends to excite room bass nodes and adjusting or adding further points on-the-fly. You won't do any harm and you will also learn a lot!

The amount of equalisation Larry has used suggests either that your room is really challenging or that he was being guided by you by telephone & couldn't hear what was happening to adjust himself

I actually found that once the speakers are properly time aligned and using a second sub in a different position then the need for room eq becomes almost irrelevant (but setup and time alignment using step responses with the second sub etc becomes more complex). Believe me, my room created all sorts of issues back in 2011 before I started out with this. There really are none now.... so it can be done

Time Alignment outside - Looking at the screenshot of my speakers, you can see how the main impulse is sharp and fades away clearly and very fast to a flat line until the first tiny reflection at 26.2ms. The speakers are at the extreme front edge of a narrow platform, DEQX and amps are on another table many feet away to the side and the ground, 3' below the speakers is soft grass. I believe the tiny reflections are actually caused by the mic & stand because when I measured one of the subs at 3' and then 6", the same reflection appears much sooner on the closer measurement

Andrew

(note: when I say 3', I really mean 3.28 feet, ie 1 metre but as I am an older Brit, my generation is still a bit more American than European !)

There is a much simpler way to create a duplicate or modified file: open your original file as normal in the software then immediately click 'save as' from 'File' on the menu bar (top LH corner)

When the smaller window appears, simply change the file name and save. It will then create another identical .mzd file in all but name into the same root folder as the original

Provided this file remains open while you modify or add anything, any further mods or saves will apply to this, not the original. My 'working' .mzd file was built up by multiple saves this way and eventually I went back and deleted all the older, no longer needed versions

Bruces' question: 'Btw, you referred to 'time alignment' and 'time coherence'. What is the difference between the two terms?"

My explanation is a bit lengthy (as usual!) and I cover phase coherence as well. They are inter-related....

Simple answer...
You time align speaker drivers or driver sets to each other to 'achieve' time coherence

Now the detail...
When everything starts and stops at exactly the same millisecond, such as a woofer & a tweeter or a main speaker & a sub, they are then moving in a time-coherent fashion (and are also phase-coherent)

When the BEGINNING portion of each driver or speakers' pulse arrives at the listening chair microphone or listener ears at the same instant, these are time coherent speakers. I discovered a long time ago that on my system, using the DEQX viewer and the Step Response facility, time-aligning the START of the sub(s) pulse with the start of the main speaker pulse gives by far the most natural integration and bass response. Larry has aligned Bruces' sub peak with the first impulse peak of the main speakers and both appear to start at about the same time so it should be similarly so

None of this can be relied on purely by measurement & the DEQX viewer alone however because, if you think about it, the impulse plots of any speaker or sub contains ALL the frequencies emitted by those drivers and the plot just shows one combined response against Amplitude/Milliseconds

Sound waves travel at different wavelengths/speeds from the lowest/slowest to the highest/fastest frequencies so what you are aligning to is a subset of all. Rest assured however that DEQX DOES minutely time align all frequencies WITHIN any single speaker it measures. It's just the manual bit in adding subs or anything from a diffrent measurement that needs careful interpretation to achieve the goal of 'time coherence'

That is why I have found it is best to use the plots as a guide and then fine-tune adjust by ear until 'perfect' but based on several room measurements and step responses in the viewer. It was pretty easy for me once I got to that spot because every piece of music I throw at my system sounds crisp and clear with no hint of bass bloom or a crossover

Note: with a single full range speaker containing passive crossovers, or a 2-way, 3-way measured accurately at once (ie without requiring subs), then an appropriate DEQX processor will do everything for the user and it automatically becomes time and phase coherent. All that's left to do is basic room eq or maybe time align an unequally placed speaker pair

Phase coherence means simply that the twin peaks and valleys of a test tone (such as created by DEQX during measurement), exactly line up at your ear. When those different waves also start and stop at the same time, you then have a speaker that is both phase AND time coherent

While basic 'phase coherence' is often used when setting up subwoofers, particularly 'simple' AV home setups, a phase-coherent speaker/sub may not be time-coherent. I know that because before I purchased the HDP3, my M&K sub WAS phase coherent with the main speakers & in an ideal position but the result in the room was pretty annoying to say the least. It has never moved from that spot but since setting my system up as described, it has audibly 'disappeared'

Thanks for pointing that out Al, no problem at all!

I have always tried to keep my posts quite generalistic because we seem to have several potential or new users here and many of the principles behind DEQX can seem pretty bewildering at first, offputting even

I'm sorry, I am not experienced with materials for acoustic panels. Maybe Nyal could comment as I have seen a couple of recent posts from Acoustic Frontiers

DEQX claim that their algorythm time aligns all frequencies within a given measured speaker, even if this is a 2 or 3 way, regardless of the crossover order or even physical placement of drivers on a flat or stepped baffle (measured at once - not so if a sub is then manually added for instance. That requires the manual 'best compromise' time alignment I have previously mentioned)

Therefore it is my understanding that Bruces' speakers have been time and phase aligned during measurement and calibration - within the limits of the microphone and the accuracy of the measuring environment but including the inbuilt passive crossovers

My reply relates to DEQX digital time alignment and not speakers that are physically aligned via the baffle and containing passive crossovers. Of course Bombaywalla is correct about that and the impact of the crossover order

Bruce: I think Bombaywalla and Al have answered your question very well, DEQX corrects exactly what it hears but, as you also suggested, it is still a function of crossover, driver design and build quality, plus 'voicing' of the cabinet as well

DEQX deals with distortion as long as the user is not trying to push a particular driver beyond what it is capable of or trying to over-compensate in the software. For instance, good as it is, DEQX is unlikely to provide distortion free 10hz bass from a 4" driver! When calibrating, the user must work intelligently with the measurement plots

I can report from experience with 3 very different sets of speakers that the results sound surprisingly similar in the same room. In the case of the first two, very significantly improved over the same setups used previously without DEQX and in a similar setup to the one that Bruce has. The third, my current and final configuration now uses everything an HDP processor has to offer (6 way) except the DAC

1. Shahinian Obelisks including passive inbuilt crossover driven by one amp + one M&K sub (<120hz)
2. JBL stand mounts including passive inbuilt crossover driven by one amp + two M&K subs (<110hz)
3. Open baffle floorstanders, bi amped with two amps, treble crossed at 3100khz + one M&K and one B&W sub (<100hz)

Smooth frequency response, clean, tight bass and musical clarity were very similar among all three setups. If there was a shared character, I would have to call it 'transparent and neutral'

The Shaninians, probably by nature of their multiple 360 degree radiating mid & treble drivers had the poorest imaging and a more indstinct soundstage but with huge width and depth. Still fabulous sounding though

The JBL setup imaged extremely well and had the sense of a neat but smaller 3D soundstage and encouraged me to then move on to, what I consider one of DEQX-HDPs greatest strengths - the ability to incorporate multiple amps and steep crossovers

When not listening to my home system (or with my wife!), I am normally with like minded friends listening to live music and realistic transient attack had always been my goal because that is one area I had never been able to resolve, no matter what I listened to in dealers, at shows etc - until I heard another, OB based system with a DEQX processor in it. To achieve the necessary midrange speed/cleanness I decided that I wanted to avoid any sort of cabinet colouration so started researching Open Baffle Speakers myself

I prototyped various designs for a long time before commissioning a CNC workshop to manufacture the frames for my final design: 1" thick Zebrano Bamboo floorstanders with a d'Appolito configuration of Aluminium/Magnesium midrange drivers and ribbon tweeters. Large, heavy speakers but exceptional transient speed with a real sense of musical reality...in fact unbelievably so on a lot of recordings

One other comment about DEQX correcting 'what it hears' - I do have experience of comparing music corrected from an in-room and outdoor measurement of both the Shaninians and JBLs and although in theory the software should correct to the same resulting sound, it does not. My in-room measurements always resulted in a slightly unnatural, nasal hollowness to music playback and with my desire to achieve 'perfection' it wasn't quite good enough

Hi Bruce, my OBs only handle 100hz and upwards - each using four mid range drivers plus ribbon tweeters. All these are physically aligned (to the originating point of each) within a flat, tall and wide baffle & the speakers also have shallow tapering 'sides' which blend to the top edge. Sound waves can pass across the front surface and away to the sides but are constrained so they also transmit (only) to the rear. Nothing else behind the speakers apart from cabling and a single protective capacitor for each tweeter

There is free space beside and behind the speakers and I have no obvious issue with back reflections or wave effects/cancellations - but that's not to say they aren't there, it's just not apparent and I have no reason to check. The music room also has a lot of diffusing and absorbing material including a great deal of vinyl (+ CD storage)

In everything I have done, listening and then adapting has been the mantra until I achieve the sound I want - this has always been referenced to natural sounding live music. Research, theory and specifications are extremely useful but the real question should be 'what does music actually sound like'?

Sure, I made mistakes and I produced multiple low cost OB prototypes - each time I heard something I wasn't happy with, I then researched that particular aspect and adapted until it sounded right. My original intention was to try out OBs, learn and then build a pair of Linkwitz-Rileys but my own developments started to sound so good that I saw no need to follow that path. Maybe I just hit lucky or it's probably more likely that DEQX is capable of fully correcting something that is nearly there already?

I am confident that in my room and with my (mostly analogue source) preferences, this system is about as good as I could hope for

I have done nothing more to my setup for at least 2 years and can find no fault (so far). For the previous 40 odd years I constantly replaced and upgraded.... 'chasing the wind' as it were. Not any more and that's why I am very happy to see Bruce, Al and others starting on the same path because I know that the end point can be so satisfying

Congratulations Al, an excellent summary!

You have been very thorough in measuring your speakers and I am sure Nyal will give excellent advice to get the best from the system

We all look forward to your further updates

Hi Swampwalker, I have sent you a PM with my email address

A very interesting summary Al and I sympathise with the challenges you face

At the risk of repeating myself (apologies), are you absolutely sure that there is no chance of taking an outdoor speaker measurement?

I originally made several attempts to achieve a good indoor measurement but none came close to those taken outdoors. Once I saw the cleanness of the resulting plots, any further speakers or subs were always measured this way - including manhandling a huge Miller & Kreisel sub into the garden and then up onto the measuring platform which was a great deal of effort

It does make a significant difference and I believe that is why music created from the resulting calibrations sounds so remarkable. I am rather a 'perfectionist' so I couldn’t have rested knowing that I wasn't getting the maximum performance from DEQX

Yes, this can involve a lot of time and commitment (in my case around three hours from start to finish, moving the gear etc) but provided you use a high number of averaged measurements (I recommend 1.4s/96K x at least 18 sweeps) and the day is completely dry without much wind, the measurements only need to be taken once and are extremely accurate, virtually anechoic if done well. Any random birdsong or other faint wind noises appear to be completely disregarded by the averaging feature of the software

Somewhere I may have photographs of the setup but they are not on this computer so I will have to look for them. If anyone is interested I would try to find them plus some of the resulting measurement plots and post them as images on 'my page'

I have posted a couple of screenshots under 'System' at the foot of my posts for anyone with a DEQX processor to compare the plots

The measurement shows how 'clean' the frequency plot may look relative to an indoor reading that others may have taken and the impulse response illustrates that there is only a tiny reflection from the microphone itself

(The measurement is a raw image from the mid-high range speaker before any correction & at 0% smoothing. Indoor calibrations tend to use up to 100% smoothing and a closer windowing, both of which reduce accuracy and have an impact on the sound in my experience)

I can only report my own experience and with music playing, it sounds totally believable from the outdoor measurements. Using the same settings from calibration to configuration with the best indoor readings I could achieve, music and especially mid-bass had a slight hollow-nasal quality to it and was not as natural

I am using Open baffle speakers which I appreciate are very different to those being used by Al, Bruce etc but this quality was also present in the full range Shaninians when comparisons were originally made

I feel at a loss to convey with words just how close to perfect a well set up DEQX enabled system can get. For sure there are still going to be a lot of very satisfied users provided measurements are taken to the optimum in the environment available

I'm sorry to say that I don't quite agree with that last sentiment Bombaywalla. Unless someone has heard this themselves, they may not understand how good the resulting sound can be from a good indoor measurement and the majority of people will be extremely satisfied with that

Its a bit like saying that someone buys a top-range sports car but only drives it to 60% of its speed-handling capability. Another owns the same car but takes it to track days at a local circuit. Who is to say which owner gets the most pleasure?

DEQXs' main selling point is the ability to tame the room/speaker interface and it does that better than anything else I have experienced - we are talking about degrees of perfection here and each user will have different expectations

I mentioned a slight nasal quality to mid bass and by 'slight' I really do mean that. Many people probably wouldn't even notice or worry about it. I have listened to two other European DEQX setups, both sounded amazing and the owners were very pleased. Neither sounded quite as smooth or natural as mine does....to MY ears and MY tastes, which is the point I am trying to make

Bombaywalla - Without re-reading my earliest posts, I believe I may have mentioned my reaction from the very first time I played the DEQX corrected system. I swore out loud - it was that good compared to what I was familiar with. That was from the initial (indoor) measurement

Over extended listening I noticed the slight nasal quality and after re-running the measurements outside I was able to eradicate this. I expect a first time listener may not notice that, or more likely, others may not be as critical as I am

It's not possible to answer that question Ptss, I'm afraid because there are too many variables involved, not least the impact the room has on the sound and your ability to optimise that.

However speaking personally, I am confident from the experience I have that DEQX can significantly improve any speakers/room you would be confronted with because I have already done this several times using a DEQX processor.

The JBL 250Tis are a 3-way design and if you are brave enough to do it, bypassing the internal circuitry and using 6 channels of amplification (ie HDP-4 OR HDP-5) and digital crossovers are what I would do.

Even a Premate or Express will help you get the best from these without modification but whatever you consider, the end result will only be as good as the time and effort you are prepared to invest.

I am a DEQX user (HDP3 since mid 2012) and for me it has certainly been a game changer. It is not an easy product to set up and takes a great deal of research and learning to perfect. I now consider myself quite experienced. This was once I properly understood all the nuances of crossover slopes, phase, time alignment and room effects. What follows below is a simplified description of the procedure for using DEQX. The manual itself is lengthy and in many cases not easily comprehended (ie not difficult to get it wrong in several important aspects)

Originally I calibrated and used a pair of existing Shahinian Obelisks and the improvement compared to the sound I was familiar with was very dramatic. This was with the standard passive crossovers in place and blended to a pair of subs. By time-aligning these and with subtle room equalisation below 250hz, it was the first time that the crossover to the subs truly became seamless and all room effects disappeared (no exaggeration). I remember swearing out loud when I first got this, it has to be heard to believe it!

After a few months and fully appreciating what the DEQX could do, I decided to build a pair of Open Baffle speakers. Mid-sub crossovers are at 100hz (72db slopes), mid-treble at 3145hz (60db slopes). Extreme slopes allow individual amps and driver sets to operate within a narrow band and this creates very clean and dynamic transients

The beauty of DEQX is that you can calibrate these outdoors (raised ideally above grass, not a hard surface and no walls around so there are only very faint and unimportant reflections to corrupt the microphone reading) - the software creates a flat frequency response, which can be verified. Then when a mic is placed at the listening chair indoors, it compares with the original 'anecholic' result and time aligns all the drivers including phase at each frequency etc. All you then need to do is further manually time align the separately calibrated subs, if you use them. Very clever and effective - sitting in the sweet spot is holographic & 3D sounding. Performers 'hang' in space before you, realism way beyond anything I have heard in a hi-fi dealer demo, exhibition or, frankly anywhere else including some very expensive and otherwise impressive systems. My own speakers also manage to beat the Shahinians in every respect but I suspect this is more to do with 3 separate frequency bands being opimised for each driver set and very steep crossovers. The way this was described to me is like the latest military aircraft or Airbus. These are intrinsically unstable but sophisticated software allows them to fly. In the case of a fighter jet, often way beyond the realms of normal aerodynamics. I think that is what the DEQX algorithms do

Oh, and by the way...everything you do can be listened to using 4 presets to compare and changes made in real time whilst music is playing (including time alignment which I can only describe like turning the dial on a lens until suddenly everything falls into crystal clear focus, very useful)

DEQX is also an excellent preamp, completely neutral and very analogue sounding to my ears (I play a lot of vinyl) and also contains very good DACs (only bettered by a new Graham Slee product called the Majestic. I had previously used a Chord 64 and the DEQX DAC was much more musical, the Slee even more so)

I only caution someone borrowing and trying to set this up themselves in a short time. You may get 50-60% of what is possible but not appreciate what it can really do. When you do eventually dial everything in correctly, there really is no going back. I probably sound like I am preaching so sorry about that - I am 57 years old, have been fanatical about music all my adult life, am extremely fussy about realism and my loft is full of expensive but ultimately unrewarding hi-fi kit. If anything, after 2 years, I am more enthusiastic about DEQX that I was before

Hi Lewinskih01
No problem, I will mail you. I am in the UK

Yes a single DEQX processor handles 6 channels/6 amps. You could add a second of course (I may one day add the latest HDP4, these things are very expensive but worth every penny)

My setup is:
Treble, 2 channels +3145hz
Mids, 2 channels 100-3145hz
Bass, 2 channels -100hz (2 separate subs, different placements)

I originally purchased the HDP3 because I could not integrate the sub (single M&K MX200 at that time) to the Obelisks without occasional audible crossover dips or humps which drove me crazy. The DEQX made the crossover seamless and I was happy for the first time. It's going to be a compromise for you: Because with only 6 channels you may need to either take the clarity and image realism using the DEQX for the main speakers and live with imperfect sub integration or maybe combine mid-bass or mid-treble on the main speakers so you achieve the cleanest bass. I would take this route personally. Whatever you do I am happy to assist as much as I can

Hi Lewinskih01
No problem, I will mail you. I am in the UK

Yes a single DEQX processor handles 6 channels/6 amps. You could add a second of course (I may one day add the latest HDP4, these things are very expensive but worth every penny)

My setup is:
Treble, 2 channels +3145hz
Mids, 2 channels 100-3145hz
Bass, 2 channels -100hz (2 separate subs, different placements)

I originally purchased the HDP3 because I could not integrate the sub (single M&K MX200 at that time) to the Obelisks without occasional audible crossover dips or humps which drove me crazy. The DEQX made the crossover seamless and I was happy for the first time. It's going to be a compromise for you: Because with only 6 channels you may need to either take the clarity and image realism using the DEQX for the main speakers and live with imperfect sub integration or maybe combine mid-bass or mid-treble on the main speakers so you achieve the cleanest bass. I would take this route personally. Whatever you do I am happy to assist as much as I can

Answering After_hrs question, the difference in the quality of music after setting DEQX into the system is so astounding that it is impossible to compare the amps

An important aspect here is that when you measure & correct the speakers (ie outdoors) and then calibrate, re measure and correct in the listening position, this is with each amp/channel as you will use in the final setup. Source components (in my case Vinyl/CD/SACD/Streamed FLAC) only play a part during final time alignment tweaks or equalisation on-the-fly whilst listening to music. This is a really good feature so you can arrive at exactly the sound you want

DEQX corrects what the mic hears and therefore the impact (or otherwise) of each amp is taken into account. The end result just sounds lifelike and 'neutral', without colouration. Equally importantly, all the bass humps and dips have audibly disappeared and the room/speaker interface has no bearing on the sound. DEQX will also enable you to take bass to unbelievable levels if you so desire and if the drivers will allow it. At the same time it remains uncoloured - hard to believe it is possible until you hear it

Another example is that I have tried 3 different types of speaker in 2 different rooms with a different power amplifier controlling the midrange and if used correctly, the end result is remarkably similar. I have changed to different brands for mid and treble in my current setup and it has no discernable bearing (and I am someone who knows that system/room intimately). That is very impressive

If there is a downside, apart from the relative complexity in learning the process correctly, it is that I now spend all my spare time in that damned music room and my already vast music collection grows weekly :)

Lewinskih01

I did not require my other preamp because the DEQX does this very well, reducing components in the signal path and it is transparent sounding

It has both digital and analogue inputs, balanced and unbalanced (HDP4 has USB as well but I don't need this)

The DEQX has analogue volume control outputting to the power amps (digital volume option included) and yes, I have used the onboard DAC which is very good, configured as below:

CD transport input to Balanced Digital XLR, onboard DAC, then onboard XO/speaker correction, output to external treble/mid/sub power amps, then to Speakers & subs (likewise for a Digital streamer to coax unbalanced Digital phono input etc)

A Turntable and SACD player use the phono and balanced XLR inputs

The DEQX does indeed result in a 'dream system'. I have had more than 2 years of pure pleasure since I installed mine and the realism and clarity never ceases to amaze. It makes a good system great and a great system simply unbelievable!

- I hope that Bifwynnes' dealer is up to the task and can achieve all that it can do (ideally measure the speakers first outdoors, it makes a big difference to doing it in the listening room. I have tried both)

From the first evening I started to set up DEQX, I appreciated the dramatic change made to my system. No need to ever remove it - its effects are immediate and noticeable

At first, all I wanted was a means of integrating two subwoofers properly and the HDP3 took care of that very quickly

What floored me was the unexpected clarity that I had no idea my system was capable of. I was trying to listen to the bass but it was as if everything coming from my speakers was now in a different league

Although it took me about 6 months to fully understand and perfect everything, I will never surpass the amazement of that first night. An 'audiophile' friend visited the following week and asked 'OK what's the trick, you have added some sort of surround sound?', another simply said 'where do you go from here' and basically, more than two years later the answer is 'nowhere' (after changing to DEQX crossed-over Open Baffles)

It's that good

So, Psag and Ptss, here is no need to remove DEQX from the system - nothing else I have heard comes close to this and the realism of the music is often breathtaking. If and when my HDP3 processor stops working, I will buy an HDP4 (or better if they ever produce something) immediately and without hesitation

Ozzy
Yes you can set the DEQX yourself, Bifwynne is just arranging a demo by the dealer

Calibrating is relatively easy once you follow the (enormous!) manual and most aspects have automated settings to get you a long way down the track. Achieving the final 20-30% to 'perfection' takes more time and many don't bother. I did and it is worth it

There is also a chargeable service called DEQXpert where you can dial in and be guided through setup if need be

It is not that difficult to calibrate DEQX using the manual and most processes are automated. This achieves a lot of what it can do without specialist skills. It is only the last part, interpreting the graphs to achieve precise time alignment to subs that takes understanding

The best aspect is doing this whilst listening to music so you can instantly hear when it is dialled in correctly

A novice can still hear a significant difference and for most this will be a long way beyond the sound they had before (speakers corrected for phase & timing at all frequencies and room effects removed)

Bifwynne
Measuring outside gives plots on the software where the first reflection is quite distant and easily identified - this helps greatly with the accuracy of the calibration

Measuring inside does colour the result and when I compare by listening, an inside measurement/calibration sounds more hollow and artificial whereas an outside measurement results in very pure and neutral sounding music

If your dealer is willing and the weather permits, I strongly recommend you take this option. It will really show how special this processor is

If you measure indoors, DEQX will hear room effects and the calibration will be much less accurate & the finished result compromised. It can still be effective, just not as good as it should

Here's a youtube video of someone doing it from their car (white coat optional !!)

http://www.youtube.com/watch?v=n1tSsj-DK1A

If you live in a house with a garden then great & use an extension lead, if you don't then I guess you have no other option for now

So, if you have to go with an indoors measurement, lift the speakers up in the air ('platform' in the centre of the room, put the speaker on it and measure one at a time of course, making sure you record which measurement relates to which speaker), preferably angled slightly upwards - cover the floor in front with cushions and other soft materials to kill the reflections as much as possible

If the dealer is doing it correctly, he will know all this anyway

I used to use DEQX for both analogue/digital, now only analogue (although it contains an excellent DAC, I now use something even better). The two analogue inputs are configured as below

1) RCA Phono analogue input: Turntable/phono amp
2) XLR Balanced analogue input: balanced connection to Graham Slee Majestic DAC/preamp. This has an anlaogue input that I use for SACD/second TT, plus multiple digital inputs (coax, optical, USB) for the CD transport/digital streamer/laptop etc

I also use the DEQX analogue volume control. Overall there is no trace of anything 'digital' in the sound I hear which is a testament to the smoothness of the DEQX processor. You have to hear it to believe me of course!

Psag, yes I am introducing further conversion but the musical benefit easily justifies that for me. Using the inbuilt DAC, digital sources were a little more 'fatiguing' to listen to. Maybe it's the combination of open baffle speakers/ribbon tweeters which are very revealing of the tiniest details

The Majestic DAC is very analogue-like and neutral & I hear less harshness at the extremes of treble. If I play the same album on vinyl and then CD, the resulting sound is very very close. If there is a drop in transparency and resolution, I don't notice it

Actually Psag I actually like very clear but smooth treble and both my TTs use cartridges that achieve this: AT150ANV and Ortofon 2M Black. Neither can be called rolled off

Digital sources now have a very close signature. The harshness I described in the DEQX DAC was very minor but I am extremely picky! (I also have a Chord 64 DAC and that IS rolled off)

My 'real' love in this hobby is live amplified music and I spend way too much on that. DEQX in my system using all my sources gets me remarkably close

Glad to hear you had a successful demo Bif. I am happy to help if you need any advice once you receive your unit. Did you go for the DEQX Mate?

Interesting observations by Forrestc and Bifwynne

I became an 'advanced' DEQX user and learnt over the past two years how to improve my initial setup with small tweaks and modifications along the way. You do eventually reach a point where further meddling becomes unnecessary and counter productive of course

Learning was by a combination of email support from Alan Langford at DEQX, from my own dealer (DEQXpert), from discussing with other DEQX users and studying the principles behind time alignment and how to properly interpret the graphs. I wouldn't say I am particularly 'tech savvy'.... more inquisitive and willing to experiment and learn

For anyone reading this who is not a DEQX user and put off by the apparent complexity, don't be - most setup widgets have a default setting as part of the automated process and DEQX takes care of phase and time alignment of the speakers automatically. It is only alignment between different speaker sets (ie main-subs) and room effects that require manual intervention. These two aspects can be adjusted in real time and with music playing so the resulting changes can be heard immediately

There are 4 presets so you can make different versions of a similar configuration, modifying one aspect subtly between them and change via the remote whilst listening and then settle on the best one. My final setup has 4 similarly configured presets with the only change being the amount of bass boost/room eq to compensate for a bass heavy album (preset 1) all the way to a thin sounding album (preset 4). Preset 2 is used for most listening (by the way I have never used the hundreds of eq settings available on the remote and the use of preset 1 as a 'Bypass' is only worth it the first time you ever use DEQX, after that I have configured it as with the other 3)

Ruler flat eq curves do indeed sound very dull - for instance if you use the 'inverse' eq facility to map and neutralise the room frequency plot, it sound too sterile. Learning how to work with DEQX to achieve a natural and full sounding frequency range 'in your room/to your taste' can be both time consuming and enjoyable at the same time

Adding two subs to the room (directly fed by the DEQX as Bif mentions) makes a big difference as does experimenting with the crossover point. I tried several settings between 80 and 120hz before finally settling on 100hz as the most natural sounding - below that the OB speakers struggled to fill-in and above that, mid-bass started to sound a little 'nasal'

In my experience, building passive crossovers and sloped baffle speakers and using acoustic room treatment CAN achieve similar results but it is so much more 'hit & miss'. You normally get one go at a crossover and invariably find fault over the subsequent weeks & months. It's a real hassle to then make changes and always a bit of a stab in the dark. Likewise with acoustic treatment I could take out SOME bass humps but never satisfactorily fill in the voids.

With DEQX, the potential to correct with music playing until it sounds exactly as you want is infinate. Maybe for that reason alone, I do consider it to be a game changer

Quote: "Al, you and I are both old enough to know that some questions are best not asked. I'm "freeze tagging" on the DEQX's analogue functionality viz my phono. The thought that my Ref 5 SE could be an irrelevant artifact is too difficult to bear"

I am nearly 60 and although I also have around 4000 CDs, a few dozen SACDs and (at last count) around 54,000 (!?) mostly FLAC digital files (Rock, Hard Rock, Blues, Folk, Indie, Electronic, Folk) I still prefer Vinyl through my DEQX - 2 TTs via phono amps. 3 very fine preamps are now in other rooms or unused and will never be in the main system again

Bif, SACD has a sample rate of 1 bit/2,8224Mhz vs 16 bit/44.1Khz for standard CD. It cannot be handled by a conventional DAC so processing is done by the SACD player and enters the DEQX via an analogue input

I believe the CD-8 will only play regular redbook CDs, SACD requires a dedicated player (inc some Bluray players)

There are also relatively few SACD disc being produced these days, most of mine were purchased when originally issued. As always in audio, mastering of the original recording has the greatest audio impact (IMO), so a really great CD or digital file sounds better than a so-so SACD or LP

I have a lot of FLAC files at CD quality, quite a few at 24/96 and some at up to 24/192. The same comment about mastering applies so I don't get too hung up about it. The 'best' vinyl beats everything else but then maybe I am a dinosaur?

"Bombaywalla or perhaps Drewan77 --- what is the DEQX's digital capabilities?? Can I use the CD-8 as a transport and the DEQX as a pure DAC to play SACD?"

No, you can only use the onboard DAC for up to 24/192 processing, not SACD. It is good for CD or streamed MP3, FLAC, ALAC, WAV etc. The CD-8 can be used as a CD transport but for SACD you need to input from a dedicated player via one of the analogue PreMate inputs

In theory, adding additional processing into the signal path should have a negative effect. Maybe...but the benefits in my experience greatly outweigh any theoretical drawbacks and I only hear improvements. I certainly cannot detect any loss of transparency - in fact I have never had such a sense of real performers in a believable soundstage

Contributing to this thread has made me put a lot of thought into what it really is about DEQX that I find beneficial. So, in order of significance, this is the impact on MY system after using DEQX for two and a half years:

1. The ability to adjust almost everything on-the-fly whilst listening to music in your own room. - Irreplaceable, I could no longer own a system without this feature. Everything else was 'guesswork, trial & error'

2. Measuring & correcting non time-coherent speakers. Phase and timing is aligned at all frequencies, not just a 'theoretical' passover compromise - Huge impact

3. Time aligning subs - Huge impact, it is no longer possible to detect a crossover or any nulls or peaks, no matter what type of music is played

4. Ability to create crossovers at up to 72dB slopes and adjust crossover frequencies so amps & drivers operate in narrow & more efficient frequency bands, also the choice of different crossover types - Very big impact

5. Room correction - Reasonable impact (not so necessary when all the above are already dealt with anyway)

6. Preamp ability - Neutral... it seems to have no sonic signature I can detect. One more analogue input would be useful, that's all

7. Four presets selectable by remote control, each giving a slightly different adjustment to the lowest frequencies to compensate for thin or bass heavy albums - Not often used but very useful when necessary

8. DAC. Very, very good but slightly clinical - I can live without this

9. The ability to create and save further equalisation from the remote control (a huge number of presets) - Not used

Additionally:

- Ease of setup - logical but a lengthy process to do it properly. Automated widgets make a pretty good result quite easy and far simpler than any equivalent DSP I researched. Take the time to understand it and the results are fabulous

- Ease of use once understood - logical, practical and infinitely adjustable until 'perfect' at the listening seat

- Overall, the combination of 1-5 above makes the effect of your room an irrelevance and it no longer has any audible impact on the music you play. - therefore this equipment is irreplaceable (for me)

As I have said previously in this thread, please keep an open mind until you hear a fully corrected system. I was one of the biggest cynics out there until I decided to try it for myself

Bif, when I compared the DEQX DAC to the Chord 64 I was previously using, it was more lively sounding and I happily used this as a replacement. I like very precise transient attack, including bass that is clean & deep but starts/stops very fast. Much more realistic to true life and the DEQX DAC has that

The DAC I changed to at the beginning of 2014 was auditioned first and sounded just as lively but somehow has almost the same analogue 'smoothness' as vinyl (input via the HDP3 balanced XLR input). It gives me exactly what I was looking for

I did a back-to-back comparison yesterday to check again before posting and the DEQX DAC still sounds slightly more artificial and brittle at the extreme top end, a bit more 'Hi-Fi' than natural to my ears

Answering about the Chord DAC, this was input to the DEQX via the phono analogue input so maybe this has some bearing on the slightly dull sound. Having said that, my current DAC inputs via the balanced XLR analogue input and sounds fabulous, definitely smoother and more realistic than the DEQX DAC

Answering about isolation, I already use expensive chords, a dedicated electrical circuit and power conditioning so I am confident that is sorted

Answering about the Chord DAC, this was input to the DEQX via the phono analogue input so maybe this has some bearing on the slightly dull sound. Having said that, my current DAC inputs via the balanced XLR analogue input and sounds fabulous, definitely smoother and more realistic than the DEQX DAC

Answering about isolation, I already use expensive chords, a dedicated electrical circuit and power conditioning so I am confident that is sorted

Allmarg is correct, apologies if I confused everybody, in my country a single ended input is often called a 'phono' socket. A phono stage is something else entirely

I should also point out that the latest HDP4 processor uses an entirely different (presumably improved) DAC compared to the HDP3 that I have. I still maintain that the primary benefit of DEQX is the speaker correction facility. Anything else is a bonus

"So, if I have a Dac that I like and only want the speaker correction function , is there a Deqx unit that just does that?"

Yes, the DEQX Mate does that. Use this link....

http://www.deqx.com/product-deqxmate-overview.php

....and look at 'comparison' on the drop down RH side bottom to see the various features of each processor

(Apologies to Almarg as I notice I accidentally added a second L to his forum name)

Psag, maybe you misread what I said - here was my comment from an earlier post:

"when I compared the DEQX DAC to the Chord 64 I was previously using, it was more lively sounding and I happily used this as a replacement. I like very precise transient attack, including bass that is clean & deep but starts/stops very fast. Much more realistic to true life and the DEQX DAC has that"

The Graham Slee DAC sounds more life-like than both, being fed either CD or FLAC files. It's just as dynamic as the HDP3 DAC but more realistic at the top end. You are correct about the logic of converting an analogue signal though, it must surely have a tiny impact (I tend to judge a system on what I hear though)

Psag: "Drewan77, I didn't realize you were using the DEQX mate, which does not have the digital inputs."

I am not using the DEQX Mate, that was a reply I gave to Ozzy as he was looking for something with only speaker correction. My DEQX is the HDP3 which has both analogue & digital inputs, including a DAC which I no longer use

Psag: "Drewan77 if you are using the HDP3, then you are utilizing its DAC. The device operates in the digital domain. The last step is digital to analogue conversion."

Partly true...I will explain:

The internal DAC for processing incoming CD or streamed data is not used as the processing is handled by an external DAC & these sources enter the DEQX as analogue signals (via balanced input)

You are of course correct that once inside the HDP3, digital conversion takes place but this is to process the crossovers, speaker calibration, phase, timing etc which is entirely different to the internal DAC handling the initial music processing. That is a separate standalone component of DEQX which I am not using

Alan Langford from DEQX Australia has viewed this forum topic and emailed me as below:

"....Andrew, Just noticed your last few posts, it would be good to point out that your HDP3 used DACs from Analog Devices AD1853. The New HDP-4 & PreMate use a DAC by Burr Brown PCM-1795 and completely new I/V and analog output stages that has completely changed the sound when compared to the HDP-3. All the latest models are complete redesigns other than the DSP and some logic...."

I will only find out when I eventually change to an HDP4, it is quite possible that I may prefer this DAC over the HDP3