"Archimago" on MQA

Oh, my...., posted on January 25, 2016 at 17:09:57
Ivan303 Audiophile Posts: 48887 Location: Cadiere d'azur FRANCE - Santa Fe, NM Joined: February 26, 2001	"Not sure who this person is, or what to make of this..." Some here do. ;-) First they came for the dumb-asses And I did not speak out Because I was not a dumb-ass

It means..., posted on January 26, 2016 at 08:43:13
JeffH Audiophile Posts: 4574 Location: Orange County, So Cal Joined: April 5, 2000	that you'll have to get you QB-9 upgraded...

:-) /n, posted on January 26, 2016 at 09:27:51
Ivan303 Audiophile Posts: 48887 Location: Cadiere d'azur FRANCE - Santa Fe, NM Joined: February 26, 2001	n First they came for the dumb-asses And I did not speak out Because I was not a dumb-ass

Who?, posted on January 26, 2016 at 11:27:06
E-Stat Audiophile Posts: 37666 Joined: May 12, 2000 Contributor Since: April 5, 2002	Why, he's the Faerie Queene sorcerer of course! "he is continually engaged in deceitful magics"

Or maybe , posted on January 26, 2016 at 13:45:20
JeffH Audiophile Posts: 4574 Location: Orange County, So Cal Joined: April 5, 2000	Just a software upgrade, as I read a bit further...

MQA or not to MQA..., posted on January 26, 2016 at 18:58:22

AbeCollins
Audiophile

Posts: 46302
Location: USA
Joined: June 22, 2001
Contributor
Since: February 2, 2002

If it requires a new DAC, no way. If I can do it strictly in cheap software it might be worth playing with but it's not like the current state of digital music playback is in need of the "next big thing" IMHO. I'm perfectly happy where I'm at and reluctant to spend money on what might be a non-starter. I work in tech and I've learned not to be an early adopter. ;-)

As for Archimago, I don't think his test equipment is up to the task so his measurements are meaningless. But even if they were, unless the sonic improvement is truly jaw dropping to the average listener, and not just the self proclaimed golden ear audiophool, I'll be on the sidelines laughing.

RE: MQA or not to MQA..., posted on January 26, 2016 at 19:16:50
ahendler Audiophile Posts: 5151 Location: San Antonio, Texas Joined: January 24, 2003	Good post Abe. I totally agree. My current digital playback is stunning and I doubt there will be a "Jaw Dropping" effect with MQA. If Tidal will stream MQA and provide a built in decoder for playback I would try it but I would not buy a new dac. Alan

But you 'might'..., posted on January 26, 2016 at 20:01:10
Ivan303 Audiophile Posts: 48887 Location: Cadiere d'azur FRANCE - Santa Fe, NM Joined: February 26, 2001	buy another USB > S/PDIF XMOS box IF it included the decoding hardware for MQA as well, I'm guessing. ;-) I might too. Not even sure where all of this MQA decoding takes place? Before the DAC? Is it part of the DSP? First they came for the dumb-asses And I did not speak out Because I was not a dumb-ass

How is Archimago's equipment not "up to the task"..., posted on January 26, 2016 at 21:59:06
Jaundiced Ear	and why does it make his measurements meaningless? JE

RE: But you 'might'..., posted on January 27, 2016 at 06:48:38
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	If there's a cheap entry point into MQA for 'playing around' I might consider it too. But not if I have to dump my current DAC.

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 06:56:22
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	This has been discussed numerous times here in the Asylum but fundamentally, it lacks the resolution and noise floor to measure to the levels he 'thinks' he is measuring to, making his measurement conclusions meaningless.

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 11:23:57
Bob_C Audiophile Posts: 2667 Location: NY Joined: July 31, 2000	Thank you. He is measuring atomic particles with a yardstick. I myself have some questions doubts regarding MQA, and would like to hear it and see what it is about... But his comments are pretty useless IMO.

RE: MQA or not to MQA..., posted on January 27, 2016 at 13:45:37
Isaak J. Garvey Industry Professional Posts: 1207 Location: Hollywod, CA Joined: January 7, 2016	It requires a new DAC or a DAC that can be upgraded via firmware.

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 17:14:25
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	Nice yardstick and atomic particles analogy. I agree.

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 17:43:09
Tony Lauck Audiophile Posts: 13629 Location: Vermont Joined: November 12, 2007	Whack the cat with the yardstick and if it meows it's not dead. Tony Lauck "Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

What? , posted on January 27, 2016 at 17:52:10
Ivan303 Audiophile Posts: 48887 Location: Cadiere d'azur FRANCE - Santa Fe, NM Joined: February 26, 2001	DAC-rolling AbeCollins not willing to dump his current DAC? You're good for a new DAC every six months! ;-) I, on the other hand, plan on keeping my Audio-GD multi-bit 'ladder' DAC for some time so MQA will have to be software if at all. First they came for the dumb-asses And I did not speak out Because I was not a dumb-ass

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 19:50:44

Jaundiced Ear

I think you're being a bit hyperbolic when you say his measurements are "meaningless." Perhaps they could be more precise, but that does not make them meaningless.

If I ask you how much an amplifier weighs and you say "bushels of carrots," then that would be meaningless. If you say "fifty pounds," then that is not meaningless, even if the amp actually weighs fifty two and one half pounds.

Lots of folks on this forum have taken shots at Archimago. It certainly is easy to make claims. However, I don't recall seeing anyone here actually demonstrate that his measurements are so far off as to be useless. Instead, his measurements appear to be good enough to support his claim that the bulk of digital audio is mostly the same and that the variations being offered are way out in the realm of diminishing returns.

Are there differences between formats? Probably. Are the differences "night and day?" Probably not.

JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 20:00:34

Jaundiced Ear

LOL!

Atoms are tiny. I mean really tiny. If we are saying the difference between two components is just a "hair's breadth," in other words a very small difference, then an "atom's breadth" would be about one million times smaller.

If the differences between various digital formats are truly analogous to the size of atoms, then who cares? Who could even notice?

JE

http://hypertextbook.com/facts/MichaelPhillip.shtml

RE: How is Archimago's equipment not "up to the task"..., posted on January 27, 2016 at 20:26:15

Jaundiced Ear

The difference in size between the diameter of an atom and one meter is vast, something on the order of one to one hundred billion. Are you really asserting that Archimago's measurements are off by a factor of one hundred billion or is your post itself pretty useless?

RE: MQA or not to MQA..., posted on January 27, 2016 at 20:37:26
ahendler Audiophile Posts: 5151 Location: San Antonio, Texas Joined: January 24, 2003	Or an outboard converter for your dac or software decoder built into a streaming service Alan

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 04:31:54

Dave_K

Abe has a valid point that Archimago's test equipment is not up to the task of measuring hi-res digital audio sources. However, Abe's point is irrelevant to this topic since Archimago is simply analyzing the files in software and not measuring anything.

I think his analysis is fine for what it is, but it doesn't really shed any light on the more controversial claims of MQA. Claims such as "MQA corrects for errors at the A/D and D/A stages" are unverifiable via any real world measurement system that I can think of. Which is quite convenient for Meridian and all the press that have joined the marketing effort, and guarantees that we'll be arguing about this in audio forums for some time.

OT: TOSLINK with Audio-GD, sounds great!, posted on January 28, 2016 at 07:18:37

Ivan303
Audiophile

Posts: 48887
Location: Cadiere d'azur FRANCE - Santa Fe, NM
Joined: February 26, 2001

"We have a player modify to support 192K, feed to Master 7 is no issue.
We applied the 25M optical receiver, but I can't warranty working well with your devices. All mac notebook in China have not optical.
Kingwa"

Looks like only other limit is the TOSLINK transmitter and the cable. Can say that using the TOSLINK cable above from a Mac Mini to the Master ll via TOSLINK cable above the only difference is that the 'click' or 'stutter' at the start of a new playback queue common on the Master 11 (Audio-GD does not mute when no input) is more of a 'click' than 'stutter' with TOSLINK. Only used TOSLINK up to 24/98 so far and it sounds every bit as good to my ears as USB w/Regen on it's stock switching supply.

First they came for the dumb-asses
And I did not speak out
Because I was not a dumb-ass

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 08:03:22

Fitzcaraldo215
Audiophile

Posts: 1120
Location: Philadelphia
Joined: September 7, 2008

As I understand MQA, perhaps incompletely or inaccurately, the corrections it applies are in the time domain, mainly as a result of apodizing filters in the a-d and the d-a, including those DACsin current pre-MQA Meridian players. These filter ringing issues are visually verifiable now. I have seen enough scope traces in reviews, etc. to understand the high frequency pre- and post-ringing that occur both in the recording itself from the a-d and in the DAC from the d-a. Those scope traces are abundant, as are those showing improvement as the result of apodizing d-a filters.

I believe it is possible for MQA processing of the recording to apodize and to clean up that ringing in the recording, provided the a-d filter characteristics are known. When played back on a non-MQA DAC, this can still provide an audible advantage, though the non-apodized d-a will introduce its own pre/post ringing. When played via an MQA DAC, apodizing also reduces pre/post-ringing from the d-a. Possibly, my understanding is oversimplified.

The point is, scope traces, which are measurements, ought to be able to show these improvements. I have not seen them yet for MQA. But, I believe we will someday. I also tend to believe, for now, in the potential audible advantages of the apodized filter approach.

The major problem to me is not the theory of MQA, though, like many, I do not claim to fully understand it yet. The problem is with the timing of public announcements, the limited amount of technical information they contain, wide availability of good comparative A-B listening auditions, etc. The roll out process seems to have jumped the gun as far as we consumers are concerned, with many negative opinions so far, based on too little actual evidence.

Perhaps Meridian were seeking only to offer enough to first be able to bring Tidal, etc. into the fold as major sources of MQA encoded material, apparently with some success. They wanted to do this first before making a major investment in mass producing chipsets and software for the mass market. That might be prudent from a business standpoint.

But, we consumers are left with only teasers, resulting in speculation, skepticism or downright antagonism to this new, but not yet fully understood, technology. What we have mainly are raves only by audio gurus, whose objectivity might be questionable. To many, that sounds like hype. But, even audio gurus are not always wrong.

Time will tell. My mind is still open.

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 08:10:55

AbeCollins
Audiophile

Posts: 46302
Location: USA
Joined: June 22, 2001
Contributor
Since: February 2, 2002

Instead, his measurements appear to be good enough to support his claim that the bulk of digital audio is mostly the same and that the variations being offered are way out in the realm of diminishing returns.

Unfortunately his test equipment shows variations being mostly the same because it lacks the needed resolution to show otherwise. I bet his test equipment cannot account for the audible differences that some hear even as we approach diminishing returns.

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 08:14:03
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	Bob did a great job of emphasizing a point with his analogy of Archimago "measuring atomic particles with a yardstick". If you took that literally I think you're missing the point. The point being, Archimago's test equipment and setup are insufficient for arriving at any conclusions.

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 16:54:58
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	I think you're taking the atom analogy literally. It was used to make a point. If you don't get that, then there's no hope for you! ;-)

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 17:47:29
Jaundiced Ear	Actually, I was just trying to point out how juvenile and fatuous Bob_C's analogy was. I thought most of us left off the "I'm wrong? well you're a million times wrong!" type of arguments by the time our ages hit double digits. I guess I need to rethink that! ;) JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 28, 2016 at 18:45:20
Jaundiced Ear	How about the nulling in Audio DiffMaker to below -70dB? If the differences, if any, are so far down in the mix do we really need to worry about them? I'm just thinking back to the days when we only listened to LPs with phono cartridges with at best -30dB channel separation and -30dB was, at least to my ears, essentially no output at all. Certainly I enjoyed broad stereo images at the time! JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 29, 2016 at 10:03:45
AbeCollins Audiophile Posts: 46302 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	Maybe, but I thought the "yardstick to measure atomic particles" analogy was funny AND drove the point home.

RE: How is Archimago's equipment not "up to the task"..., posted on January 29, 2016 at 12:14:37
Bob_C Audiophile Posts: 2667 Location: NY Joined: July 31, 2000	I think communicating with you is rather useless. Sorry you cannot comprehend. If you think his blog worthwhile... Go in good health... Any thinking person would realize how difficult it is to measure MOST THINGS audio related even with the most expensive test equipment... So measurements done with toys makes zero sense IMO...

RE: How is Archimago's equipment not "up to the task"..., posted on January 29, 2016 at 18:26:51
Jaundiced Ear	What "toys" was Archimago using? He posted in detail what he did and what his results were. If you follow his steps, do you get a different result? JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 29, 2016 at 18:46:25
Jaundiced Ear	I thought it funny too. I just wanted to also point out how absurd it was. JE

Proving OSX superior, posted on January 30, 2016 at 08:18:01

Roseval
Audiophile

Posts: 1846
Joined: March 31, 2008

His gear is accurate enough to measure the differences between Win 10 resampler and OSX resampler proving the Win10 resampler being a POS.
So what is your problem with his measurements? :)

The Well Tempered Computer

http://archimago.blogspot.ca/2015/11/measurements-apple-mac-

RE: Proving OSX superior, posted on January 30, 2016 at 13:49:06
SBGK Audiophile Posts: 444 Joined: March 22, 2012	do any audiophiles use direct sound ? It's audibly low quality. So yet again the poor man wastes his own and others time and comes to an incorrect conclusion. http://mqnplayer.blogspot.co.uk/

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 13:11:33
Tony Lauck Audiophile Posts: 13629 Location: Vermont Joined: November 12, 2007	Human hearing is able to resolve down to air molecule level. This has strong evolutionary benefits. Tony Lauck "Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 13:16:08

Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007

Attempting to measure high quality (or purported high quality) equipment with medium quality equipment is a fools errand. In general, one needs equipment that is a decimal order of magnitude better than the device under test, or else one needs super skills at instrument construction, instrument calibration, data reduction and statistics. (You will find people with these skills at CERN and other physics labs and at national standards bureaus.)

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 14:20:49

Jaundiced Ear

I think you're overstating your position. Human hearing is designed to respond to air pressure, but I'm guessing that it takes more than one air molecule to stimulate the ear.

Think of it: the ear drum is not made up of one atom, but millions of them. So is the bone structure in the ear. So are the hairs in the ear canal. So is the fluid in the ear canal. Having mass, the overall structure of the ear has an inherent inertia. I seriously doubt a singe O2 molecule, or CO2 molecule, or whatever kind of single, gaseous molecule striking the ear drum will be able to overcome the inertia present in the ear and so be "heard."

JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 14:33:31

Jaundiced Ear

So only people at CERN or other physics labs at national standards bureaux are capable of measuring things? If so, how on earth do equipment manufactures get any work done? ;-)

I disagree that measurements made with less than SOTA equipment have no value. Perhaps measurements made with SOTA equipment may be more valuable, but even poor equipment can be capable of giving us a "ball park" measurement, and perhaps the ball park estimate is good enough to allow us to make a judgment.

In the case at hand, Archimago has shown that the differences between the formats, if any, are more than -70dB down in the mix. That may not be the precise figure, but it at least tells us the differences, if any, are small.

JE

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 15:41:38
Bob_C Audiophile Posts: 2667 Location: NY Joined: July 31, 2000

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 18:31:01
ahendler Audiophile Posts: 5151 Location: San Antonio, Texas Joined: January 24, 2003	Don't we all know that many of these differences are small? I don't need any measurement to tell me that. Just my ears Alan

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 18:33:21
ahendler Audiophile Posts: 5151 Location: San Antonio, Texas Joined: January 24, 2003	Thanks Alan

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 19:22:01

Jaundiced Ear

Aren't the folks touting MQA saying it is revolutionary? That it "unlocks the resolution that is inside of digital files that we've never heard before?"

In my mind at least, for something to be revolutionary, heck, to even be meaningful, it's going to have to bring more to the table than differences -70dB down in the mix. I think Archimago's post is helpful in alerting consumers to proceed with caution with this product.

JE

https://www.youtube.com/watch?v=qsQ4KYELek0

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 20:40:20
Bob_C Audiophile Posts: 2667 Location: NY Joined: July 31, 2000	We need to laugh... :)

RE: How is Archimago's equipment not "up to the task"..., posted on January 31, 2016 at 21:13:28

Jaundiced Ear

And thank you for so consistently giving us something to laugh at!

Keep posting those videos!

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 12:05:05

jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001

Do you understand what you are talking about with the -77dB difference from Diffmaker? What difference is he measuring in this? This is NOT the difference between an ordinary file played through a DAC & the same file with MQA treatment played through an MQA ENABLES DAC. What archi is attempting to measure is how close the MQA file might sound compared to the standard file when both are played back through a non-MQA enabled DAC - in other words how much does MQA encoding affect the playback on an ordinary non-MQA DAC.

You don't seem to understand what Archimago's "measurement" even mean, never mind how useful they are.

It's always interesting how those with a particular axe to grind, latch onto any measurement, no matter how dubious to support their mindset. In this case you wildly misinterpret what Archi's article is about, as evidenced by your repeated quoting of his Diffmaker measurement as some sort of evidence that MQA is not providing any worthwhile sonic value.

I guess you also missed this in Archi's article "Sure, I would be curious to have a listen to an MQA decoding DAC."?

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 13:21:12

Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007

I am not overstating my position. This is known physics. It also relates to the design of microphones and explains why those that attempt low noise performance have to have large diaphragms. (These microphones do not have omnidirectional capability at high frequencies because of their larger size, also known physics.) Complicating matters is the question of bandwidth, which determines the time over which the ear averages these molecules.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 13:54:12

Fitzcaraldo215
Audiophile

Posts: 1120
Location: Philadelphia
Joined: September 7, 2008

Can you cite a verified experiment where a human perceptual difference was detected after the addition or removal of exactly one molecule of "air" in the ear canal? Actually, I would be much more interested in how they could actually do that, rather than the perceptual results. Some amazing experiment! But, as you say, it is well known. Ignorant, unsophisticated me, I am just totally unaware of it.

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 14:12:18

Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007

I never said that the human ear responds to a single air molecule. What I said is that it responds to the level of air molecule motion. Specifically, the thermal motion of random air molecules hitting the ear drum creates a noise spectrum and the ear is sensitive to this noise spectrum (or just about so, within a few dB, depending on the individual).
Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 14:21:08
Dave_K	If the difference on playback between an MQA enabled DAC and a non-MQA DAC is greater that -70 dB, then one or the other is broken! When comparing two different reconstruction filters at a hi-res sample rate of 88.2 KHz or higher, the difference should be a lot smaller than that.

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 15:24:21
jkeny Manufacturer Posts: 502 Joined: May 4, 2001	"If the difference on playback between an MQA enabled DAC and a non-MQA DAC is greater that -70 dB, then one or the other is broken!" Who ever said that? I think what Archi measured should be visited before passing comment, don't you think that would be wise?

RE: How is Archimago's equipment not "up to the task"..., posted on February 1, 2016 at 19:44:26
Jaundiced Ear	Thanks for the reply! I stand corrected. I wish you all the best in your business, although as you probably surmise, I'm not likely to be a customer. :-) JE

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 00:00:59

Jaundiced Ear

"What I said is that it responds to the level of air molecule motion."

OK, if this is what you are now asserting, then what's your point? Can't we say that all sorts of things respond to the level of air molecule motion? Like birds, or airplanes, or clipper ships, or ocean waves, or buildings being blown apart by tornadoes, or kites, or internal combustion engines or who knows how many other occurrences. What does this have to do with audio?

JE

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 04:55:29

Dave_K

In the case of the -77 dB result, there was no measurement, just a diff of the digital files.

If I understand the process correctly, MQA encoding as described in the AES paper should be transparent to at least the 16 bit level. So the differences between the clips Archimago compared are almost 20 dB higher than they should be. I can think of a few possible reasons why:

a. The MQA encoded file is not sourced from the same master as the original offered for comparison, in which case it's not a fair comparison.

b. The MQA encoded file was doctored in some way prior to encoding, in which case it's not a fair comparison.

c. The MQA process is not as transparent/faithful to source as claimed.

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 04:58:03
Dave_K	I think you're looking at it the wrong way. In theory, MQA encoding should be transparent to the source at least to the 16-bit level, so you should not see -77 dB differences between the files.

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 05:14:14
jkeny Manufacturer Posts: 502 Joined: May 4, 2001	Other possibilities: - Diffmaker's results are not reliable - for instance, it's known that the first 200mS at the start & end of the files being compared causes unnaturally high difference values - an edge effect - Diffmaker is particularly sensitive to phase differences - it's really impossible to use Diffmaker to evaluate the audible difference between two files

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 07:36:33
Dave_K	I'm leaning against blaming Audio Diffmaker because it looks like he selected an appropriate clip and you can actually see a difference in the spectrum plot.

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 14:18:45

Dave_K

The only way to remove ringing added by the anti-aliasing filter at the front end of the chain is to make the cutoff frequency of the reconstruction filter lower than the anti-aliasing filter.

Anyway, looking at the impulse response of a reconstruction filter is misleading because an impulse is an impossible signal. The digital signal being converted by the DAC is necessarily band limited prior to and during A/D so it can't be an impulse.

Note that if the signal contains no (or at least very little) spectral content at or above the cutoff frequency of a brick wall filter, the filter will not add ringing. That condition is nearly impossible to satisfy with 44.1 KHz sampling, but fairly easy to satisfy at 88.2 KHz and above.

So the issues with hard band limiting at 20 KHz don't apply to high sample rates. And since MQA is designed to be an efficient container for high sample rate recordings, I can't see the justification for introducing a FR roll-off equivalent to 10m of air in order to obtain a visually appealing impulse response. This would not be an improvement IMO.

I think MQA is trying to be too many things at once. I like the idea behind the packing method. But I'm not happy it's tangled up with a scheme to license Meridian tech at both ends of the chain, on a basis that is technically questionable, and backed by a marketing campaign that is confusing and in part misleading.

Maybe I'm being too skeptical, but I have a feeling that Meridian is being intentionally vague so they can't be pinned down.

RE: How is Archimago's equipment not "up to the task"..., posted on February 2, 2016 at 21:18:41
Jaundiced Ear	What should we be seeing then? JE

RE: How is Archimago's equipment not "up to the task"..., posted on February 3, 2016 at 07:44:33
Dave_K	Let me put it this way: What good is an encoding scheme intended for high-res audio if it's not even transparent to the 16-bit level?

Computer Audio Asylum

"Archimago" on MQA

194.126.37.40