Al, please clarify/confirm what you are reporting. At this point, I think you are saying that your DEQX is being used in bypass mode ... no signal corrections yet. If so, presumably there should be little or no impact on the signal as it passes through the gizmo, which is pretty much what I am getting from your post.
Btw, your dealer's cautionary comment about resisting over-correction is what Larry, the DEQXPert, told me.
Please keep us posted about progress.
Regards,
Bruce |
Got is Al. So, at this point, have you completed your empirical assessment of the DEQX's D/A and A/D "pass-through" transparency??
Al ... as I have already posted a couple of times, a respected dealer once told me that sometimes you have to take 2 steps back to go 5 steps forward. My point is simply that empirical observations re the DEQX's touted transparency aside, ... it's still an artifact.
This may come off as a contradiction, but I believe the DEQX does something to the signal integrity on top of what it's supposed to do. Frankly, if I had my druthers, I wouldn't use it. But with my speakers, in my room, the DEQX adds a lot more than it takes. Life is about compromises.
Regards and please keep us posted about your progress.
Bruce
P.S. -- Al ... You may have caught the thread about the Ref 150 SE upgrade. ARC upgraded the circuits in my Ref 150 to better accommodate the KT-150 tubes. Wasn't cheap, but I think there's a significant improvement in SQ. The upgrade is still in break-in mode, so I hope to hear some continued improvements. |
Unsound, when I speak of the DEQX as being an "artifact," I am only saying that it is a component that is stuck in the signal path. Period!! Of course, its very purpose and function is to change ... and quite significantly so ... the signal when engaged.
Stated differently, IMO, the best scenario is one in which one's speakers are already *perfectly* time aligned and the room is perfectly neutral. Ergo, no need for the DEQX at all. But alas ... such is NOT the case with my rig and I suspect with most others' rigs.
Bottom line: 2 steps back and 5 steps forward. Net positive sum improvement, which I believe the DEQX has achieved for me.
@Al ... just an fyi. When Larry the DEQXPert time aligned my speakers, he had me shove a bunch of pillows or seat cushions in front of my speakers. The pillows attenuated the fist reflective floor bounce off the woofers. That may help with your speaker correction results.
@Psag ... your anecdotal experience is consistent with what Al reports. Your results are indeed amazing and good to know since I too am a DEQX owner. |
Agree with Psag. Supposedly, there is a user manual on line, or buried in some of the program files somewhere. For what we are paying for this gizmo, I would sure appreciate having a hard copy, user-friendly instruction manual. |
Al, sorry I didn't respond last night to your message. My internet was down until after 11pm. You asked:
"When the DEQXpert people calibrated your speakers, how far did they end up placing the microphone from them?"
My recollection was about 36 inches as measured from the tweeter.
"And if you know, how many milliseconds after the direct sound arrivals did they place the point at which subsequent arrivals were windowed out?'
Don't remember ... sorry.
Al, what I do remember is that Larry, the DEXPert, asked me to take precise measurements of the speaker height, including the space between the drivers. In addition, Larry asked me to take precise room H,L and W measurements, including the distance the speakers were placed from the front wall and the distance my listening position was from the back wall. He also asked to me to position the mic at the precise spot of my ears. No kidding!!
Please keep us informed of your progress. And have fun!! :) |
Drewan ... in your opinion, did Larry "time align" tame my beasts pretty well? Ditto room correction?? What is the significance of "windowing at 24 ms"?? What is better ... a long or short ms time frame? Or is the question a non sequitur?? |
@Al ... just an fyi. Maybe Drewan can weigh in a little, but my general recollection is that my room wreaked havoc up to 500 Hz. Plus, my speakers weren't all that flat north of 500 Hz.
Another point. Larry basically cut the S8's woofers out of the picture. He used my subwoofer to do the heavy lifting below 120 Hz.
Part of the problem related to the room for sure. But also, the mid and tweeter drivers are wired in reverse polarity as compared to the woofers. So he reversed the overall polarity of the signal and matched the time alignment of the mid and tweeter drivers with the subwoofer. The S8's woofers are only working from 120 Hz to about 230 Hz. The sub is picking up the load from 13 Hz to 120 Hz.
That's why I described the DEQX as turning my signal into a pretzel in order to tame my system.
Drewan, if you have my e mail address, send me a PM and I will send you the latest files which reflect Larry's most recent "fine tuning" adjustments that he did on December 4, 2014. Same offer to you Al.
Bruce |
@Al ... just a final thought. You will soon learn how the designer of your speakers wired the cross over when you do the signal impulse test. As I mentioned, Paradigm reversed the polarity of the mid and tweeter drivers as compared to the woofer to achieve phase coherence at the cross over points.
I'm sure Richard Vandersteen would cut his hands off before doing such a thing. |
Andrew (Drewan) and Al ... do you think the reason that Larry, the DEQXPert, used such a "heavy hand" with corrections to my rig had more to do with the speakers or the room?? For example, any thoughts if I were to invest in a pair of Vandies which start out time aligned?
Andrew ...going back to your point about doing time alignment corrections outside, how much improvement do you think I would achieve if my speakers were aligned that way? |
Thanks Bombaywalla. The Vandy 7s are a non-starter for me. Too da*n expensive. Also, my basement/sound room isn't big enough ... not even for the 5As. The Quatro Wood CTs might be an option.
Drewan thinks that the DEQX already time aligned my speakers. If so, any marginal improvement might be theoretical.
My guess is that it might come down to the quality of the drivers. And Paradigm's Signature line uses very good quality innards. The tweeter uses a Be dome and the mid uses a Co/Al alloy cone. Both drivers are quick on the draw.
I might try and arrange a trip this Summer to Verona and check out the Quatros at Johnny's place. He is also an ARC dealer and might be able to match up an ARC Ref amp with the Vandies.
In the meantime, I'm thinking about the sound box idea that Al and Acousticfrontiers mentioned above. It might enable Larry, the DEQXPert, to do a better job with time aligning my speakers.
Btw, you referred to "time alignment" and "time coherence." What is the difference between the two terms? |
Al and Andrew (Drewan) ... if I was inclined to put together a non-reflective sound box, do you have any thoughts about the materials I should use? I wonder what speaker manufacturers use to damp sound reflections in box speakers??
Andrew, notwithstanding the imperfect initial set up of my speakers because I was not able to do the time alignment adjustments outside, imaging and soundstage are greatly improved over what I had before. In many ways, I was playing stereo through two different speakers because of room EQ problems. I think you have a sense of what I was dealing with by looking at Larry's adjustments. |
Thanks Al and Andrew.
Al, may I suggest that you take your initial time alignment measurements a third way ... a baseline measurement. That is, no panels at all. Reason: to see how significant room reflection impact is on the speaker impulse measurements. And conversely, the extent to which your sound box ameliorates room reflections.
Your results will guide me on next steps.
Thanks |
That's a great response Bombaywalla. So, in the absence of owning a speaker that is time coherent/aligned ... like mine which are NOT, the next best solution is DEQX. IMO, I think the DEQX really tamed my speakers and my room.
One can drop all the money in the world into electronics, cables and so forth. But, IMO, I think time coherent/aligned speakers are the way to go ... PLUS, the room HAS TO BE RIGHT. My room sucks and I have no other options. The DEQX cleaned up a lot of my audio problems.
Another question is driver distortion: harmonic and intermodular. I wonder if the DEQX fixes those issues too. I suspect not. As an fyi, the Magico S5 is one of the lowest harmonic distortion speakers I recall ever seeing tested. I don't recall seeing any speaker tester report on IM distortion. I wonder if it can be tested??
See this link: http://www.soundstage.com/index.php?option=com_content&view=article&id=1043:nrc-measurements-magico-s5-loudspeakers&catid=77:loudspeaker-measurements&Itemid=153 |
Al/Andrew/Bombaywalla ... any thoughts about the impact (if any) DEQX has on driver distortion? My guess is that driver distortion is more a function of crossover and driver design and build quality itself. And that it is outside the realm of the DEQX to correct such deficiencies.
Just an fyi: Here's some bench test measurements of my Paradigm S8s (an earlier version #2): http://www.hometheaterhifi.com/surround-sound-speaker-systems/surround-sound-speaker-systems-reviews/a-secrets-speaker-system-review/page-4-the-paradigm-reference-signatures-on-the-bench.html
Not bad ... at least in the opinion of the reviewer.
My S8s (v3) use the same tweeter and mid drivers. The woofers and x-over were upgraded. Nevertheless, I assume the distortion specs would be about the same as those reported for the V2.
Even still ... compare the Magico S5s in my post above. Almost vanishingly low distortion specs. I suppose the real Q is whether we can hear the difference. Stated differently, assuming the Magico S5 and Paradigm S8 were DEQX corrected, how differently would they actually sound?
I gotta' believe that a 500 Hz test signal produced by the Magico sounds exactly like a 500 Hz test signal produced by the Paradigm S8. The real Q is how do the two speakers make music after being DEQX corrected??? |
Thanks again Al and Bombaywalla. More great responses from Al and Bombaywalla.
Al, I think your quote about using the DEQX with active x-over function (and I assume this entails multi-amping) answers my driver distortion question:
"High dynamic resolution (reduced distortion) due to drivers operating in linear operating zone.
"Reduced crossover distortion - reduced ‘comb filtering’."
But I think your following comment may say it all:
"I'd imagine that the main benefit DEQX can provide with respect to driver distortion would be in cases where subs are being used (as in your case), or in biamped or triamped setups. In those situations DEQX could introduce very sharp filter slopes that would keep some of the drivers from having to deal with frequencies that are out of their comfort zone. And it could do that without the adverse timing and phase effects that would result if that were done in speaker crossovers or elsewhere in the analog domain."
Al/Andrew/Bombaywalla: There is only one speaker that I know of that uses super high-order internal/passive x-overs; namely: Joseph Audio. I think Mr. Joseph describes his crossovers as an "infinite baffle" types or something to that effect. I'd call them brick wall filters. I bet the DEQX would do a great job with Joseph Audio speakers.
As an fyi: PJ, the DEQX National Sales Manager chap I spoke about before is also the local rep for Joseph speakers. He speaks well of them.
Next to last point ... as Al and Andrew both know, I use a self powered sub (1700 watts; 3400 watts peak) that Larry, the DEQXPert, folded into my system. I think Al makes a good point that using the sub diverts low frequency signal away from my main amp, thereby reducing the power demands placed on the amp.
Last point ... I wonder out loud if I should even ponder upgrading my speakers at any time in the future. Perhaps, the best next big step, which would entail taking a whole different path, is to do what Andrew has done.
Namely, DIY speakers with excellent drivers ... and no internal crossover. Instead, I would use the DEQX as the cross over and I would multi-amp each speaker.
Very expensive path. I wonder if Duke LeJuene (sp?) from AudioKinesis could custom build the speakers. |
Thanks Andrew. Based on the collective comments coming in from you and Bombaywalla, I am thinking that I am at a "stop point" with speaker evolution. If there is a next step, it may be an off the beaten track approach that Andrew has taken.
Btw Andrew, if I correctly understand your custom design, your drivers are mounted in an open baffle frame. What is your experience with back reflection from the drivers? Any wave interference and cancelation effects? Many manufactures try to damp the back reflections in damped sealed structures (e.g., Paradigm and Magico) or use a transmission line approach (e.g., Vandersteen).
Also, many manufacturers like Revel design the front baffle to minimize wave inference effects. How does your design speak to front baffle interference issues?
Back to my original point, ... I am interested in reading about Al's set up experience with the sound box. As previously posted, it is not physically possible for me to move my speakers outside for an "anechoic-type" set up. Nevertheless, perhaps Al's sound box experience will persuade me that I can approach that goal.
P.S. Although I have reported this before, I believe that the DEQX PreMate has been a high yield investment in my rig. I am dubious that dropping $30K Magicos ("sans" DEQX) into my rig would yield a lot of grins if the music doesn't "sound" quite right because of time alignment issues, or if the room twists the FR of each speaker into a pretzel.
Thanks again guys.
Bruce |
Addendum to my last post ... it occurred to me that there was another factor that may have impressed my stepson other than the DEQX. Namely, since his last visit, I sprung for the SE upgrade to my ARC Ref 150 amp. As many may know, it involved switching out the KT-120 tubes for KT-150 tubes, plus ARC made some proprietary circuit changes. Now I'm not sure.
But what the heck ... my rig sounds better than before and that's what counts. |
Wanted to post a report about an interesting and enjoyable audio experience.
Several years ago, I bought a Best of Roy Orbison 2 record reissue set. I was always disappointed because it seemed that Roy's voice was shifted to the right. It got to the point that I used the balance control on my linestage to shift the imaging. But the music still didn't sound right. Imaging was smeared across the sound stage, even when I played the record in mono mode.
Well, I got bored with the record set. Actually ... disappointed. So I put the record set away. I haven't played it since I bought my DEQX PreMATE ... that is until now.
So here's the report: Roy's voice is exactly where it should be ... dead center. The background singers and band appear to be properly placed too. Also, Roy's voice is not screechy like it was when I first played the LPs (Pre DEQX). As many may recall, the guy could belt out a song and he had quite a vocal range.
Since I'm still using the same phono pre, TT and cartridge, I attribute the sound improvements in staging and voicing to the PreMATE. Just sayin' IMO.
Cheers
BIF |
Al,
Can you copy the impulse measurements from your best test. In a perfect world, I surmise that all drivers should be in sync. |
Thanks Al and Andrew. I guess I'll hold up on buying the panels for a bit. I'll wait for future reports.
Andrew, it may be that I will bite the bullet and schlepp my whole rig outside one day. Gotta tella ya though ... I am concerned about damaging gear by doing this.
As I've already mentioned, my rig is tucked away in my basement/sound-room. At a minimum, I'd have to haul up the steps: two 100 pound speakers; an 80 pound amp; and the DEQX. And what about my 110 pound sub?? I assume I can leave the other gear downstairs. |
Happen to agree with Andrew's last post. Let's be patient while Al noodles his way in setting up his HDP-5. I surmise Al will be able to put this issue into perspective. |
Thanks for the update Al. I've been offline since Tuesday/Wednesday and haven't been tracking your progress. I looking forward to reading your future reports.
As you know, I already shared with you via a PM Larry Owen's general philosophical comments about speaker and room correction. I sent a copy to Nyal as well.
Al ... I intend to send you a PM with some room measurements and maybe some pics too if I can figure out to work my cell phone camera. I'm not sure I buy into the point made by Larry and PJ that my speakers and sub are too big for my room. I think my room is so crappy that it could mess up speakers of any size or quality.
BUT, the DEQX tamed my rotten room situation so that is more tolerable. In fact my stepson came in from out of town this weekend to spend father's day with me and played one of his favorite LPs. He was pretty WOW'ed (sp?). He hadn't heard my rig since the first set up attempt.
Cheers,
BIF |
Hi Al ...anything to report? |
Al,
Logically, I should probably try going "sans" Ref 5 SE (linestage) too and solo it with the PreMATE as my preamp (like you). But I can't bear to part with my beloved ARC gear. I think ... but am admittedly not sure ... that inserting the Ref 5 SE into the signal path does little harm. So it stays.
At some point, my speaker curiosity may get the better of me, but for now I am standing down on that upgrade. I have no way of meaningfully and reliably making a decision unless a dealer is willing to permit a home audition. And even then, I'd have to reconfigure my PreMATE. Too much of a PITA. So, I'm holding where I am for now.
Maybe ... I'll take a run up to John Rutan's shop in Verona, NJ and do some serious listening to a pair of Vandy Quatro CTs. Anything larger will not fit in my basement. I'm thinking about Vandies because they are purportedly time coherent. Also, Johnny R is an ARC dealer and can hook an ARC amp to the Quattros to effect a better sound comparison. And, I've read very good reports on the Vandy CT (carbon fiber) tweeter.
Anyway ... just my late Saturday night ramblings.
Looking forward to reading an updated report when you get a chance to turn back to your HDP-5.
Regards.
BIF |
Yeah Al,
I see what you mean. Not too concerned about sensitivity. My amp is pretty muscular. Also, the low end uses a self powered woofer which should take heat off the amp.
Some of the other measurements raise yellow flags for me as well. That said, the DEQX might be able to smooth out some the Quatros' FR aberrations. I wonder how the Quatro CT specs out??
I surmise that "real audiophiles" might say, "ignore the specs; use your ear." Not sure I buy 100% to that position.
In any case, let us know how you make out.
Regards,
BIF |
Al, more questions than answers. Looking at the step response graphs. The tweeter and mid look pretty closely aligned .. off maybe a couple of mSecs. The woofer step looks unusual. Can you or Andrew explain what I see there??
Also, the group delay graph makes little sense to me. Again ... can you or Andrew interpret the graph.
I suspect that the DEQX will clean up your FR graph. Most of the bumps and saddles are probably room related.
As an aside ... just finished another session with Larry. He tamed the time alignment specs as measured at my listening position. He also spent a lot of time smoothing out the saddles and bumps. Overall presentation is more natural sound presentation.
P.S. Larry told me that he does factory authorized mods to the DEQX, many which source from the HDP-5. I may take him up on the upgrade this fall. Many of the changes relate to improved power supply, better op amps ... all of which make for faster transient response and dynamic headroom. |
Al and I already traded PMs about his progress. For the benefit of others, I mentioned in PMs to Al that room correction will take him across the goal line.
I also surmise that Al may find that he like a different room correction adjustment for each type of music that he likes. For example, he may like bass augmentation when he plays pop and rock. In contrast, he may like a flatter FR adjustment when he plays classical.
That's the beauty of the DEQX. It enables the listener to fine tune his or her system to his or her specific tastes and preferences. |
Al, your experience and comments about the sound difference between the DEQX DAC as compared to your Bryston CDP are consistent with my experience. I thought my DEQX PreMATE was a "squeak" better than my ARC CD-8 CDP, but just a bit.
I too am surprised that the DEQX is as transparent as it appears to be. I agree with your comment that "the DEQX continues to ... be perfectly transparent. Which is amazing, of course, considering the A/D and D/A conversions it puts into the signal path."
Please keep the reports coming.
Regards,
Bruce |
Andrew (Drewan77) ... when dealing with an artifact in the signal path, it's hard to get below zero when it comes to impact on the signal integrity. Not quibbling, but it is quite remarkable to me how little impact there is when sending a signal through the DEQX in pass-through mode.
What can I say ... but kudos to DEQX. |
