J. Peter Moncrieff, editor of International Audio Review, had been quiet for a long time, his website having last been edited in 1999. I tried to buy back issues in 2013 without success.
But now he's reappeared, with an incredibly long winded (as usual, and I haven't read it all) takedown of MQA, and not just MQA but similar supposedly transient improving techniques in digital audio (which he calls a "modern revisionist digital engineering movement worldwide").
A lot of what Moncrieff is saying is correct. Sure, he's making mountains out of molehills, exaggerating to the max, and full of puffery and self-congratulation (which I find entertaining, actually, like listening to PT Barnum, but now if he could only be a little less repetitious it would be less tedious). But, still, much of it is correct, and I believe MANY wise old fashioned engineers would agree with the thesis that modern short transient digital filters that seek to eliminate pre and post ringing, including MQA, are WRONG at least in principle, pretty much along the lines Moncrieff is saying (though I'm not sure all his thought experiments are precisely correct, they capture the jest in a very accessible way, and his gift at doing that makes me find it worthwhile to read). The old fashioned digital filters take full advantage of the sampling theorem's promises to capture all the information in the bandwidth window, up to the limit of their technical features (such as the number of times of oversampling...which does benefit from greater than 8 times, just as Moncrieff says, though many old fashioned engineers would say 8 times is plenty good enough) and the new kind not so much--the new kind ARE information lossy, with MQA being the king of the hill in lossiness of anything that claims to be CD quality or better. If these new digital filters have benefits at all, it's through the euphonic effects Moncrieff describes, not actual higher fidelity. It's like NTSC color TV's from the 1960's, first they up the color temperature to 9000K to make it look brighter, then they add nonlinear red push to make the skin look natural regardless of that, then they peak the horizontal response to look like there is more sharpness than there actually is, never mind the false edges and other artifacts. A properly designed TV of the same basic performance would look less bright and less sharp, but would be more accurate and contain more real unobscured information to the serious viewer. A properly designed digital system may sound duller and less spacious than MQA, but it's true hifi and not euphonia. Though I'm also of the opinion the difference between MQA and regular PCM would be very hard to hear above the level of chance. Still, and then perhaps even moreso, why not have true high fidelity? And especially if you have to pay more to a middleman to have the fake. Perhaps MQA should be understood more as a watermarking system than a high resolution audio system. And the same is true of SACD and DSD-64, not that many care anymore. (I keep my vintage Sony 9000ES, with true 1-bit converter at 10x oversampling, on the grounds that to enjoy the sound the producer intended, you need to use the matching decoder, and many SACD's do indeed sound pretty good for good production reasons and despite the inherent lossiness of the system. The same is true of HDCD, which I think better than SACD, and has zero information lossiness whether decoded or not, but is dynamically lossy if not decoded.)
On another topic, one great audio engineer passed away recently was Siegfried Linkwitz, the primary inventor and promoter of the Linkwitz Riley crossover now used by many manufacturers and builders (including me, since about 1983), the designer of many great DIY designs, and creator of a website with a vast amount of incredibly detailed audio information and analysis.
This was strangely ironic for me, as about the same time as Linkwitz passing I was discussing crossovers with a friend who dismissed Linkwitz's claim that the group delay (phase shift) caused by properly implemented LR crossovers is not audible, or is at least not audible to him. My friend described Linkwitz very negatively regarding this claim. I believe Linkwitz was honest and a careful listener and these differences ARE hard to hear. Here is Linkwitz' page on the subject:
But I've long considered the idea of transient perfect crossovers to be appealing, so I've launched a new set of projects to try them, using miniDSP processors and FIR digital filters. There will be a steep learning curve in this. (Linkwitz has other pages where he details the problems in "phase perfect" approaches.) Ask me in about a year if I got anything working.
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