Is DEQX a game changer?

"I doubt schlepping the speakers and amp outside is an option either."
Then you will not hear the best that the DEQX has to offer.

"If it took me more than a few bars to hear the change interest would be lost."
Then you have a short attention span and the DEQX is not for you.

"No need to ever remove it.."
Of course not, but doing so will remind you what changes are being made by having it in the playback chain.

"Although it took me about 6 months to fully understand and perfect everything."
Exactly!

Psag, illuminate me. How the heck am I going to move a 100 pound speaker and a 75 pound amp outside. And what about power connections. I'm sorry ... I'm just am having a problem figuring out the logistics.

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 did mine in the driveway. Buy yourself a decent moving dolly and attach some protective padding. Should be under $100 total. The outdoor measurement can be done with the speaker on the dolly. All you need is a speaker, an amp, and an available outlet. The DEQX rep will take care of everything else.

Is deqx only for digital? Does anyone use one in an all-analogue signal chain?

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!

hi Bruce,
did you finally get a DEQX demo at your house? if yes, was it all that it was cracked up to be? thanks.

Bombaywalla ... my DEQX appointment was cancelled and rescheduled for next week. I was tangled up with urgent client matters that HAD to be sorted out on the 15th, which is the final due date for calendar year corporate tax returns that on extension. So, the rep rescheduled for next Monday, the 22nd.

Looking forward to being amazed.

BIF

Drewan77, by using the Gram Slee for streamer/laptop, you are introducing additional D/A and A/D steps. I tried this as well using top-rated DAC and analogue preamp, but I found that transparency and resolution were slightly improved by running the digital source directly to the DEQX. For CD and vinyl, I continue to use my tubed preamp.

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

Ah, so you like the top end rolled off a little bit! Just kidding, I'm sure it sounds great.

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

(Somebody told me there's a reward for posting the longest message)

If you prefer to use your own DAC with DEQX [and your speakers aren't bi/tri amp-able] you can use the DEQX's dig-in and have the convolved signal exit DEQX's mid/full dig-out right into your favorite DAC. If you do have a bi/tri amp-able system you can run those 2/3 dig-outs into multiple DACs.

I got into DRC about a year ago and [given my ADD] it's a miracle I was able to accomplish anything. The stereo is that one hobby that promises immediate gratification -- I've been conditioned to wait not longer than 30min for tubes and stuff to warm up.

DRC is funny because it's the last thing an audiophile would purchase (certainly after cable upgrades), and it's effect is on the scale of a speaker upgrade, which would have been your first purchase. I spent good money on tweaks to combat the issues unique to my speaker/room/seating interaction. I'd spend a few hundred dollars on something and it was a challenge for my ear to detect that something changed at all, and along comes DRC software which all but made fun of my whole upgrade process. For me DRC's most evident improvement is how it makes speaker cabinets vanish like Totem Rainmakers. Other things are improving but that's what hits me first when trying it on different speakers. At this point I'm proud to say I've receeded to all budget cables (bluejean speaker, bluejean AES, belkin USB, and a variety of affordable RCAs).

I don't doubt DEQX is an amazing appliance. Last time I researched DRC hardware I didn't see any that had dig-in. Accomplishing this stuff in the digital domain prior to the first D2A is important. It's impressive that DEQX learns your speaker independent of the room effect. Those additional parameters must yield amazing results.

But this is my situation:

-My Thiels are already time aligned and I don't use subs

-I've got this giant vaulted ceiling with giant traps, speakers are 3ft off a back wall that is 37ft wide, and my focus is on my room's response to my speakers, and not my speakers. When I measure different speakers the graph shows a common suck-out and hump in the low frequencies.

-I'm all digital, so EQ'ing analog sources is not an attraction

-I'm a budget audiophile, so my "expensive" [worst case] solution would have been forking out $500 for Dirac Live.

My first taste of EQ was in Foobar using the MathAudio Room EQ plug-in. I then spent $100 on a FocusRite 48v mic preamp and a $60 mic. Eventually I spent around $50 to have Herb @ Cross-Spectrum Acoustics create a calibration file for my microphone. I did some free trials of affordable software but weeks turned into months and I conceded to take the beaten path started Dirac's 30day trial. That's when I learned my tiny netbook (Intel atom) would take several minutes to generate a filter. So I spent about $600 on a faster computer (Intel NUC - I call it my pocket computer), switched from Foobar to JRiver (which was yet another learning curve), and I spent $500 on Dirac.

In the beginning I thought my only issues were between 30hz and 700hz. Eventually I learned my whole system was out of phase and once that was corrected I discovered wonderful improvement when I ran the filter all the way up to 20khz. The other thing I learned is that a target curve that asks for aggressive "up EQ" will easily clip and therefore require the DSP gain to be set lower, and if the DSP gain is lower than 50% (-4db) then you aren't getting your money's worth. So I start my filter above my room's bass suck-out frequency (83hz) and this allows me to crank the DSP gain way up.

I'm now at a point where I use a single filter for all my music, but playback is now like driving stick. Each recording affords a certain amount of headroom for "up EQ" (generally the same for an entire album), and you want the DSP gain set as high as possible without Dirac's clip indicator redlining. So I'm always tinkering with the DSP slider which makes me feel like a DJ. So far it's not a bother for me -- I suppose when it does I'll start experimenting with JRiver's auto-leveling feature. 2 years ago I would have scoffed at a product that couldn't resolve above 96khz, but I've grown to appreciate the fundamentals and my priorities have since changed. I now would prefer to hear a 320kbps mp3 with DRC to the 24-192 version w/o DRC.

Its true that this technology can make decent equipment sound like audiophile equipment. This is not an attractive feature for some, such as those who have invested megabucks in their analog gear, and some reviewers who are invested in the status quo. But then again even Mr Analog Jonathan Valin is now promoting DSP, although his editor is still stuck in the 20th century.

Wynnytsky, given the challenges imposed by your room, you might want to consider adding dual subwoofers. DSP plus dual subs is a match made in heaven.

Psag -- my preamp and my integrated don't have additional outputs for a sub so I'd have to use REL subs. This is sort of a blessing because I'm spared the additional expense of exploring this avenue.

For me the term DSP conjures up memories of Yamaha's church and hall effects. I wouldn't be surprised if audiophiles are turned off by DRC for that same reason.

For those who are steadfast against altering the signal instead of treating the problem (room, speaker, crossover, etc) I would say you should still purchase a DRC product. It's like a 3d virtual tour of what your system would be like if a team of Swedish engineers pimped your rig. You still get your money's worth even if you don't take the anechoic measurement or convolve each driver independently with bi/tri amplification.

I think in the future we'll see more audiophile DACs offering additional channels but less will be done in firmware and more will be done in software. Software will be able to operate the 3+ outputs to do bi/tri electronic EQ or steering 2ch music into 3ch audio, and DRC will be available on all channels. My interest in convolving a 3rd ch peaked a couple years back, but that didn't seem to be within my reach so I settled for DRC.

For those thinking about measuring outside, for practical reasons I don't do it. The last DEQX calibration that I was involved was with a pair Apogee Full Range and at 300 pounds each they ain't going anywhere! Measuring outside lengthens the time it takes for the calibration microphone to hear the first reflection. Longer the time until the first reflection, the lower in frequency your calibration will be accurate. Recently, after talking with Nyal Mellor of Acoustic Frontiers, I normally don't try to correct anything below 500 or 600HZ anymore. I seem to get better results now rather than trying to correct all the way down to 250 to 300 Hz or so which is usually where the first reflection places its limit on lower-end calibration when measured indoors.

Normally when I do a DEQX calibration indoors, I move the each speaker (if movable) one at a time to the center of the room and perform a measurement then move it back. I also toss some blankets of the floor between the microphone and the speaker to be measured, then perform the measurement. The first reflection usually comes from the floor or ceiling.

What I saying is that by not measuring the speakers outdoors is by no means a deal breaker. You can get great result measuring indoors. Just use the Earthworks M23 or M30 calibration mic. If you have large speakers with large ribbon drivers or large array like Apogees, you will probably find that you will get the best results if you measure the speakers anywhere from 5- to 7-feet back rather than the recommended 3-feet.

The DEQX home demo was completed last night. I am buying the DEQX.

Not being inclined to the use of vivid hyperbole, I do not think the DEQX is transformational. But I do think the improvements are considerable and significant enough for me to spring to buy the DEQX.

I will follow up with a more detailed report after I finish drafting and editing my thoughts.

More to follow.

BIF

Thanks Drewan.
Well Bif, can't say I'm even a little surprised based on all the favorable comments. I think you will now be the envy of many of us as you get to learn and dial in your new unit. Enjoy and please keep us in the loop. We'll all learn.

Congratulations, Bruce! Glad to hear that the time and effort you've put into this assessment has paid off.

Best,
-- Al

Bif, thanks for the update, anxiously awaiting the full review.

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?

09-23-14: Bifwynne
The DEQX home demo was completed last night. I am buying the DEQX.

Not being inclined to the use of vivid hyperbole, I do not think the DEQX is transformational. But I do think the improvements are considerable and significant enough for me to spring to buy the DEQX.

awesome!
I'm happy to read that you now recognize the importance of time coherence to music playback. :-)
it IS very significant.
The time-coherent speaker manuf weren't barking up the wrong tree - no sir, they were not...
So, anyway you can make your speaker time-coherent will work to significantly improve your listening pleasure: apply a Band-Aid like DEQX or buy a time-coherent speaker from the get go.

Bruce, maybe you'll be transformed in time to come. I'll poll you in about 6 months & request you to pull out the DEQX from your system & give me your opinion. I'm wagering that you won't be able to listen to your system ever again without DEQX.... ;-)
That's what happened to me - once you get use to a time-coherent speaker system there is NO going back even for a few seconds....

As others have already written, I too await your report after you've collected your thoughts. Thanks.

Drewan ... I bought the rep's demo, which was a PreMate. So I have DAC capabilities ... to be explored and understood in the coming days and weeks.

Bombaywalla ... the DEQX device can cut-out the correction circuit and step out of the signal path ... if you believe that is truly possible. If so, I can compare the DEQX correction on the fly --- in and out. It "appears" that when the DEQX is cut-off, the rig's SPL seems lower as compared to when the DEQX is engaged.

The DEQX guys explained that the SPL isn't really lower. Rather, when the DEQX is cut-off, I am turning up the gain to try and capture the missing "X-factor" correction the DEQX adds. In fact, when the DEQX is engaged, I can turn the gain down a little and the presentation is just fine.

As I understand the DEQX guys' explanation, an important "fix" is in the midrange frequencies, which are most noticeable when corrected. So ... when the mids are time corrected and room equalized, I simply "hear" the music qualitatively better. Ergo, I don't need to crank up the SPL.

The DEQX seems to have tamed my rig. It would sure be helpful if other audiophiles could listen to my rig and validate what I think I hear.

Al (Almarg) ... if you're ever in my neck of the woods, feel free to stop by and have a listen. I greatly value your opinion.

Thanks for the invite, Bruce. I'll definitely keep that in mind.

I bought the rep's demo, which was a PreMate. So I have DAC capabilities ... to be explored and understood in the coming days and weeks.

Question: Have you or will you be trying the DEQX for vinyl listening with your ARC preamp removed from the signal path?

Best,
-- Al

Al, right now, my vinyl and CDP are connected in usual fashion to the ARC Ref 5 SE pre. The DEQX is inserted between the Ref 5 and the Ref 150 amp. The DEQX is "twisting" the signal there.

As I said, it's hard to know the extent to which the DEQX is affecting the sound by being in the signal path. The DEQX guys think the effect is minimal. But, regardless even if that is not so, the game is about trade-offs.

Now ... what will be interesting is if I use the DEQX as a DAC. Then my ARC CDP will feed a digital signal directly into the DEQX and end-run the ARC pre.

Btw, I understand my phono pre can feed an analogue signal directly into the DEQX too. That would obviate the need for my ARC preamp.

Using your DEQX as your DAC works very well and is highly recommended.

Al, I would bet that with a little more configuration tweaking you will be able to get even better results than you have now. Ultimately, you many need to take a few more speaker measurements at different distances to really nail it. But listen to it like it is for a good while before you make any changes.

BTW, even if you thoroughly know what you're doing when it comes setting up the DEQX, which I'm most certainly sure that your person giving the demo does, by devoting some extra time to the configuration you will usually find room for improvement, and often times substantial improvement, over your initial calibration.

Enjoy listening to music through your corrected system!

Forresstc .... I will post a more detailed report that lays out the details of my DEQX audition. It took 2 sessions. The first session was worthless because of serious room issues and my speakers are just too large for the room.

Plus, the second session involved hooking up my sub directly into the DEQX device rather than from my preamp's main #2 output. This permitted the DEQXpert to more effectively make compensating adjustments by crossing over my self powered sub at 120 Hz. Probably improved bass tightness because the DF in my sub is pretty high. My sub is a self powered solid state job.

I am dubious that an average Joe could extract as much out of my DEQX as the DEQXpert. Too many adjustments and too many beasts to tame. Also, many of the time alignment and room EQ adjustments were made based on the DEQXpert's anecdotal experiences.

For example, he did not attempt to achieve a ruler flat EQ curve. He said that twisting the drivers beyond a certain point would result in a negative yield.

So ... IMO, unless one is really tech saavy, I'd recommend paying the extra fee for the DEQXpert service.

Forrestc, stated differently, beyond a certain point, continued tweaking yields diminishing return.

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

Well stated Drewan.

Bifwynne,
Would love to hear your impressions about going direct to the DEQX using its built in preamp versus preceding it with your ARC preamp.

To me, if the preamp in it is very, very good in addition to its primary duties, that would be huge for me.

Thanks.

isn't DEQX only for digital sources? Would anyone choose to use it in an otherwise analogue vinyl setup?

sorry, didn't see the response above to this ?

I have both digital and analogue sources going to the DEQX model HDP4.The digital sources run directly to the DEQX, and the analogue sources pass through a conventional preamp before going to the DEQX. There is really no reason to use a conventional preamp in addition to the HDP4 model, other than the increased number of inputs it affords. The preamp section in the HDP4 is of a very high quality, as are the A/D and D/A convertors.

For those who would contemplate learning how to do the calibrations themselves, make sure you have a lot of free time.

DEQX Update: I used an extra XLR connector from another application to hook up the Ref CD-8 CDP digital output directly into the DEQX via the XLR D4 input socket. The acoustic sound presentation is similar, but the DEQX DAC function produces a somewhat sharper image and sound stage.

Getting a little nervous here. What happens if I try a direct DEQX analogue hook-up from my phono pre???

What happens to my ARC Ref 5 SE???

Al ... are you following this? I need some independent validation. I am trying to adapt to some major paradigm shifts here.

Bruce & Lloyd,

A couple of comments that were made earlier by some of the experienced DEQX users who have been making outstanding contributions to the thread:

08-28-14: Drewan77
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).

08-28-14: Psag
Another amazing aspect is that the preamp section is utterly transparent, to my ear, with an analog source.
[Although Psag noted on 9-18 that "For CD and vinyl, I continue to use my tubed preamp."]

09-17-14: Drewan77
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 analogue 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!

Having reviewed the information provided at the DEQX site pretty thoroughly, I see no reason whatsoever to question their observations, putting aside dogmatic biases some may have against the A/D conversion which the DEQX performs internally when provided with an analog input.

What happens to my ARC Ref 5 SE???

That was the point to the question in my previous post. Based on everything that has been said in this thread, and on the info provided at the DEQX site, it seems to me to be highly conceivable that you may get results that are as good or better with it removed from the system than you are now getting with it in the system, albeit perhaps with some slight further tweaking of the DEQX settings.

In which case you could sell the ARC preamp and perhaps more than recover the amount you paid for the DEQX.

Best regards,
-- Al

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 had the same reaction when Excel/Lotis spreadsheet software obsoleted 14 column spreadsheet paper. To this day, I refuse to use Excel. I ask the kids to run my spreadsheets when I need that work done. I love my 14 column spreadsheets, white vinyl eraser and Pentel .5mm mechanical pencil. Even to this day, nobody can run a "10-key" faster than me.

Very interesting to hear the DAC function sounds at least as good as the ARC Ref CD 8--impressive! And it seems the preamp function is excellent as well. Do we have another OPPO here? Great usefulness and great value?

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

Drewan ...can I use the transport in my CD-8 to play SACD discs? I don't know what the bit/FR is with SACD or other high resolution discs. This is new territory for me. I think redbook CD is 16 bit/44.1 KHz. What is SACD?

What about hi-rez computer downloads? I have no idea what is out there.

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?

09-26-14: Bifwynne
Drewan ...can I use the transport in my CD-8 to play SACD discs? I don't know what the bit/FR is with SACD or other high resolution discs. This is new territory for me. I think redbook CD is 16 bit/44.1 KHz. What is SACD?

SACD, as you know, stands for Super Audio CD.
It uses 1-bit DSD (direct stream digital) that is sampled at 2.8224MHz which is 64*44.1KHz. I.E. SACD is 64X oversampled compared to redbook CD.
SACD technology utilizes noise-shaping quantization techniques to recover the 20Hz-20KHz audio while at the same time pushing the unwanted noise to a higher/inaudible ultrasonic (to a human ear) frequencies. SACD, thus, almost always used delta-sigma demodulators to convert the 1-bit DSD stream to a 16-bit/20-bit/24-bit/32-bit recovered audio. The delta-sigma demodulator is digital circuit hence there is digital signal processing (DSP) done on the 1-bit DSD stream to recover the audio. The claim of SACD is that is supposedly provides a 120dB dynamic range (while 16-bit redbook CD has an upper limit of 96dB & signal processing done with 20-bit redbook also has a dynamic range of 120dB-same as SACD).
As you already know, to play a SACD disk, you need a player that is SACD capable - a redbook CD player cannot play SACDs.

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?

Btw, just updated my comments on the "Absolute Redbook DAC" thread. Too long to repeat here ... but I think the redbook DAC functionality of the CD-8 (with gain circuit) and running the analogue signal through my Ref 5 SE pre into the DEQX analogue input is a rough draw as compared to running the signal directly into the DEQX's digital input off the digital output of the CD-8 (san gain circuits of both the CD-8 and Ref 5 SE, and of course san CD-8 DAC).

Btw, still holding that the DEQX's time alignment and room EQ corrections are significant improvement. Just talking about the DEQX's digital DAC capabilities here.

"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

I was at the NY Audio Show today and the room with DEQX was high on my list. When I got there there was a tiny room with Alta Audio Three towers (likely the largest speakers of the day). I wanted to hear the DEQX toggled on/off and the presenter said they were using the DEQX in passive mode for some subs or something. His justification was to show what the speakers were capable of w/o help from EQ. Booo

I visited hotel rooms that were begging for DRC -- any flavor would due. I'm shocked that DRC is barely acknowledged, let alone showcased at a large trade show.

I was impressed to see that Vanatoo used DSP instead of crossovers to produce a flat response in their tiny $500 2way powered "computer speakers".

DEQX 'corrects' time allignment on speakers. I would rather find speakers who time allign correctly from the get go, rather than adding a unit, cables, etc. The shortest distace to good sound is a shorter, streight line.

Cerrot ... your comments, from an aspirational perspective, are valid. But aspirations do not necessarily align with reality. I suggest that you read the many posts in the "Sloped Baffle" thread. In particular, read Roy Johnson's many posts about 1st order cross overs and using sloped baffles. I recall that Bombaywalla and a few other similar thinking folks have also posted some very insightful comments.

Just an fyi, most speakers that use passive cross-overs are NOT time coherent, even if they are phase coherent at their respective x-over points. The physics is explained in the "Sloped Baffle" thread. Roy Johnson's White Papers are excellent resources as well.

To my knowledge, there are only 3 conventional driver speakers on the market that purport to be time and phase coherent; namely Vandersteen, Thiel and Green Mountain Audio. There may be others but I don't know which brands they might be.

The 3 brands mentioned above share several common design parameters. One -- first order crossovers (roll-off is at a 6db per octave slope); two -- sloped front baffles to mechanically align the voice coils of the various drivers; and; three -- drivers that operate over a wider pass band as compared to more conventional drivers.

In the case of the 3rd point in the preceding paragraph, drivers cross that over to each using a 1st order cross-over necessarily must operate over a wider pass band. By comparison, my Paradigm's use 3rd order crossovers between the mid and tweeter drivers. I believe that equates to a 24 db roll off rate. In short, each driver's operational pass band is much tighter.

While time coherent design features provide obvious advantages, they present design challenges as well. For example, drivers that operate over a wider pass band tend to be less linear. Also, their output may become congested at high SPLs and or when playing complicated musical passages.

My point is that there is no magical solution that solves every design parameter perfectly. So, be it going the Vandy, Thiel or GMA route, or using a DEQX with a more "conventional" speakers, or just living with time incoherence, ... there are trade-offs.

Welcome to our hobby.

Excellent post by Bruce (Bifwynne), IMO. Like Cerrot, in general I too am biased in favor of minimizing what is in the signal path. But digital signal processing can do amazing things these days, that often are either not possible in the analog domain, or that cannot be achieved in the analog domain without significant tradeoffs. In this case, those tradeoffs begin with the fact that limiting one's choice of speakers to those that are time coherent rules out most of the speakers that are on the market. And for various reasons, electrostatics such as Cerrot uses are not for everyone.

In any event, putting its time correction feature aside, DEQX seems like a promising candidate in its price range just for its room correction, preamp, and DAC capabilities.

One minor correction to Bruce's post: An Nth order crossover rolls off at 6N db/octave, so 3rd order = 18 db/octave.

Best regards,
-- Al

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

Thanks for the correction Al. A stupid waste of time on my part -- I checked WIKI and right you are.

Btw, Cerrot, I checked your system ... absolutely gorgeous room and STATs. Are the ESL elements full range or is there a conventional sub to fill in the bottom?? If the latter, at what frequency do the ESLs cross over?

Bifwynne,

I totally agree with you. The problem is passive crossovers. This is why I went with hybrid stats and an active crossover. I do believe the way to eliminate the time allignment issue (not talking about the sloped baffle issue, which I am familiar and have been discussing for 30 years...) is an active crossover (or single driver, obviously). In any event, I do feel the DEQX is just an attempt of a solution for an already flawed system. Remember, time allignment is not the only problem. Impedence is the issue as well. Your amp sees your speakers crossover, not your speaker.