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In Reply to: RE: Huge misconception regarding HDCD posted by Charles Hansen on June 12, 2017 at 23:26:28
I still see HDCD show up on Grateful Dead releases. My guess is they like the AD processor.
I know there are HDCD lists out there, do any of them show whether the processing was actually used?
Were the PM chips in the DACs as good as the AD processors? If I followed you, it was very expensive to use those filters, although Camelot used them in their Arthur V3 Mk2 and they were not a large company.
I answered the OP when I saw no one else had. I have to admit, my understanding was very basic, based on the propaganda.
So thanks for the detailed info.
Follow Ups:
Most of my HDCD CD's are Grateful Dead, and they do sound very good on both non-HDCD decoding machines and HDCD decoding machines. However, they sound better, to men on my CD players (NAD & Marantz) with HDCD decoding. Should that be the case given what Charles said?
Dave
> > Most of my HDCD CD's are Grateful Dead, and they do sound very good on both non-HDCD decoding machines and HDCD decoding machines. However, they sound better, to men on my CD players (NAD & Marantz) with HDCD decoding. Should that be the case given what Charles said? < <
I'm pretty sure that the Dead were early adopters of HDCD. I don't know how many CDs they released before HDCD came along. I'm pretty sure that current releases still use the PM A/D converter (which will light up the HDCD light) but it's probably been around 10 years since a Dead disc was released that actually could benefit from decoding. So the answer to your question is a big fat "maybe".
It seems there are at least two variables that one would need to have knowledge of to give a definitive answer:
1) Do all of your CDs sound better on the NAD and Marantz players, or just those that light up the "HDCD" light?
2) The fact that the HDCD light turns on simply means that the excellent sounding Pacific Microsonics A/D converter designed by Keith Johnson was used to master the recording. It does not necessarily mean that there is anything to decode. *In general*, the older the disc the more likely it would be to require decoding. Discs released from 1997 through roughly 2003 *usually* had some features engaged, as there were quite a few high-end-only CD players that could decode them. Once the decoding chips were discontinued, most people using the PM A/D converters stopped using the HDCD encoding features, and by 2007 I don't think anybody was using the HDCD encoding features - but those recordings still light up the light on an HDCD-equipped CD player or DAC.
There are two way that I know of to know with *certainty* if either of the HDCD processes were engaged on a particular disc. The free method is to download Foobar and the HDCD decoding module, then cut-and-paste the script I posted on the Head-Fi forum (linked elsewhere in this thread), and then monitor the Status Bar in the Foobar program while playing each disc.
Easier but *much* more expensive is to use the Ayre QX-5 Twenty DAC. When it detects the "sub-code" signifying a recording was made with the PM A/D converter, an LED will illuminate. If any of the HDCD features were used that can be decoded (Peak Expand and/or Low-Level Extension), the unit will decode those properly and the letter "d" will show in the sample-rate display (eg, "d44" instead of just "44") to indicate "decoding" is occurring.
As always, strictly my personal opinion and not necessarily that of my employer or dog-walker.
Hi Charles,
I am glad you saw my post. I was concerned that it might be too far down the page.
That is a very good point, and I don't know the answer. There is a Marantz universal player hooked to the same system as a the NAD, where I can do the comparison that you suggest. It was may subjective impression that HDCD's were better on the NAD, but I did not do formal listening tests. Can the Foobar program be run on a Mac? I'd love to have the Ayre, but the expense is out of the question at this time. Many of my Dead CD's were remixed when HDCD was still in vogue. They also state that they are HDCD included.
The Marantz is driving my Sennheiser HD555 headphones in the living room. Both the Marantz and Nad are Lapizator favorites, but otherwise, unremarkable in technology and they were not expensive to me. To my vinyl loving ears they sound pretty good.
Dave
> > Can the Foobar program be run on a Mac? Many of my Dead CD's were remixed when HDCD was still in vogue. They also state that they are HDCD included. < <
Sadly Foobar is Windows only. Perhaps a friend can help. I also have friend living in a full Apple eco-system with several computers, tablets, and phones. He keeps a Windows machine just for ripping CDs with dBpoweramp, as he (and I) have found that to be the very best ripping program. Perhaps you can pick up an old laptop for cheap just to run Foobar - it's a very "light" program.
If a CD states "HDCD" on the covers or liner notes, chances are extremely high that it uses the HDCD encoding features and will sound better (*if* all else is equal!) if properly decoded. What started most of the internet lists was the fact that *all* discs made with the PM A/D converter will light up the "HDCD" light on playback. The cover and liner notes say nothing about HDCD because the mastering engineer did not engage the features. People mistakenly thought they were stumbling across "hidden treasure". So another good rule of thumb is looking for some "HDCD" marking on the album artwork. If it's there, it almost certainly used the encoding features. If not, it almost certainly used the PM A/D converter but without the HDCD features turned on, and nothing to decode.
Hope this helps. As always, strictly my personal opinions and not necessarily those of my employer or Pacific Microsonics.
Charles, I also use dBpoweramp to rip and still do most of that on my PC even though it is now also available on Macs, which I prefer for almost everything else. One dBpoweramp feature that is not available on Macs is HDCD processing. That feature offers an option to boost the signal by 6dB. When would it be appropriate, or the converse, to use that feature? Thanks much for a fascinating lesson on HDCD.
All of the CD's I am considering say HDCD on the cover.
Dave
Charles:
Given the sonic superiority of the PMD model 1 and 2 when they came into existence, do you think the the high end audio world would have been better off if there had been a wide spread implementation of the HDCD process in almost all CDs? It seems to me that this would have insured that a superior sounding converter would have been used for the digital process, and that we would all have benefited with better sounding CDs (assuming that someone did not do something else in the mastering chain to muck things up).
> > Given the sonic superiority of the PMD model 1 and 2 when they came into existence, do you think the the high end audio world would have been better off if there had been a wide spread implementation of the HDCD process in almost all CDs? < <
Let's imagine a world where true high-res never came along to disrupt the HDCD business model. I would imagine that over time, more and more mastering engineers would have adopted HDCD. Let's further imagine that it was so successful that HDCD became the ubiquitous de facto standard for CD.
It would be analogous to saying that the Spectral Audio pre-amp was the world's best and it will be the only one allowed to be used by the "music police". No other manufacturer would ever be able to innovate or improve - only engineers who were contracted to Pacific Microsonics (eg, Keith Johnson).
My personal opinion is that this would be an improvement over the previous de facto standard of the Sony A/D converter, but that in the long run innovation, creativity, and improvement would be stifled. What do you think?
As always, solely my personal opinions and not necessarily those of my employer or mastering engineer.
Charles:
You are right about the need for ongoing improvement in A/D converters!
I do think that if HDCD had caught on big, that Keith Johnson would have also created better A/D converters beyond the model 2, which is already at or close to the best presently. According to your posts, most of the HDCD advantage was in the performance of the A/D converter that was ahead of it's time. Engineers still could have used other newer converters that were non HDCD as things went forward. My point was that a rapid embrace by mastering houses for the PMD converter would have resulted in quite a few better sounding CDs over the years to the present. And I am sure that PMD would have created even better filter chips at the user end.
Oh, by the way. I appreciate your very knowledgeable posts on these topics, and the lovely design work that you are doing with Ayre equipment.
> > I do think that if HDCD had caught on big, that Keith Johnson would have also created better A/D converters beyond the model 2, which is already at or close to the best presently. < <
Are you sure? This is very much like saying we should all use Spectral electronics in our system. Please don't misunderstand - I would *far* rather have Spectral electronics than a Sony receiver. But is Spectral "better" than Audio Research, Conrad-Johnson, Vaccum-State Electronics, Aexthetix, VTL, Convergent Audio Technology, or Ayre? Even if you say "Yes!", will that still hold true five years from now? Ten years from now? Twenty years from now? These are some of the issues that come along with proprietary closed formats.
As always, strictly my personal opinions and not necessarily those of my employer or pool boy.
The PM AD converter did that come in 16 and 24 channel versions? I'm thinking that with all the multi-track recording they would have to use them right from the start.
A friend of mine built a studio in his basement and the 8 channel AD/DA he has is 16/44 or 48, very outdated, but also not impressive at all.
That is one of the things with MQA, they say they have to know what converters were used. I have seen a lot of albums where the recording was done in say like 5 or 6 different studios.
With the Dead CDs, the only consistency was the stuff Jerry did with Grisman, at Grisman's home studio.
I have a Lindemann 825 that does HDCD, when using the built-in transport, but does not on any of it's other inputs.
> > The PM AD converter did that come in 16 and 24 channel versions? I'm thinking that with all the multi-track recording they would have to use them right from the start. < <
No the PM A/D converters were only two channels. They were typically used for transferring stereo analog tape masters to CD format. Multi-channel digital audio workstations (DAWs) were introduced in the early '90s but recordings made with multi-channel digital would not need to go through another round of A/D conversion. I'm guessing that the Dead continued to record to analog tape. Although this practice has become less and less common, some studios (eg, Shangri La, run by famed producer Rick Rubin) still uses this workflow - one final conversion to digital at the very end.
As always, strictly my own opinions, prone to error and not necessarily those of my employer or producer.
Always a pleasure to read your posts, Charles. I could not get the mix of technology discussion and industry history from anybody else.
I still like to understand enough about the technology behind buzzwords to be an informed consumer.
As an occasional consumer of audio gear and a regular consumer of recorded music, I look at new technology like MQA and decide whether it makes sense for me. For HDCD, SACD, DVD-A and now MQA my reaction has been "no sale". Very little of the music that matters to me will ever appear in those formats. Becoming wedded to formats like these also restricts my choices in gear too.
I buy hi-res PCM downloads instead of Redbook versions when I want to performances and the possible improvements in sound quality might be worth a modest premium. Pragmatic decisions based on value for money.
my blog: http://carsmusicandnature.blogspot.com/
"I buy hi-res PCM downloads instead of Redbook versions when I want to performances and the possible improvements in sound quality might be worth a modest premium. Pragmatic decisions based on value for money."
Tough to argue with this approach.
...better and more transparent convertors have come along since then,..and side note..DSD128 is the most analog like format i have heard for archiving. Actually virtually indistinguishable from the source.
Edits: 06/19/17
My comments about the HDCD A/D converter has no relation to the fact that other excellent converters eventually came out. That is an obvious given. As far as DSD and analog, the debate over which medium people perceive as more desirable is open to debate and opinion. I have heard really good and less good from all of the media formats, and tend to believe that much of the more obvious faults that exist are due to incompetent recording, engineering, mastering, and manufacturing.
gotcha.fyi, my comment about DSD128 was in relation to archiving...that is the key word..meaning, DSD as the delivery medium is not ideal.
An analog tape archived to DSD128 them mastered to 24 bit PCM is an excellent work flow.
Edits: 06/19/17 06/19/17
> > I still see HDCD show up on Grateful Dead releases. My guess is they like the AD processor. < <
When it was first released the Pacific Microsonics A/D was dramatically better than the then-ubiquitous Sony - which is unsurprising as not many audiophiles have Sony preamps in their systems. IMO, the PM converters are still one of the top three or four in the world from the standpoint of sonic performance. Keith Johnson is an excellent designer and knows how to make a good sounding piece of equipment. (Think of Keith's other designs for Spectral Audio, for example.)
> > I know there are HDCD lists out there, do any of them show whether the processing was actually used? < <
It is true that there are many "HDCD lists" out on the interwebs. The problem is that the PM A/D converter will light up the "HDCD" light on *any* disc made using it - even if the mastering engineer turned all of the HDCD encoding features off. This is even true for all Reference Recording (Keith Johnson's label) releases after 2009 - they continued to use the PM A/D converter as it sounds very good, but with all the HDCD features turned off as there is almost no way to decode it any more.
The way the world was able to "peek behind the curtain" was when Foobar released their HDCD decoding add-on module. If you are curious just download Foobar for free and click on the link below for commands you can cut-and-paste that will display which HDCD features are actually engaged on any particular disc.
> > Were the PM chips in the DACs as good as the AD processors? < <
In the last millennium, only three high-end manufacturers had the knowledge to build custom digital filters - Wadia, Theta, and almost a decade later, dCS. All other manufacturers used off-the-shelf chips. Of those chips, the Pacific Microsonics combination digital filter/HDCD decoder had a good reputation for sonics for several years. Its digital filter was a conventional brickwall design, but had perhaps 1.5x or 2x more taps than other brands. The problem was that it did not support sample rates above 48kHz. So for about 5 years, the PMD-100 was the "go-to" digital filter chip for high-end manufacturers and even a couple of mid-fi brands - but *never* the mass market. The PMD-100 digital filter only cost about $5 more than a non-HDCD part, but also required the manufacturer to pony up a $5,000 licensing fee, which was later raised to $10,000.
Once true high-resolution became available in the form of DVD in 1997, high-end manufacturers had to choose between high-res and HDCD decoding. I think that maybe one or two products were made (briefly) with two digital filters in order to support both. Finally PM released the PMD-200, which was a pre-programmed Motorola DSP chip that could both decode HDCD and also provide digital filtering for high sample rates. As far as I can tell Motorola only made a sample batch of these parts. They showed up in the Sonic Frontiers DACs for a short time, and then Microsoft purchased HDCD lock, stock, and barrel. For several years in the early 2000s, Windows Media Player would decode HDCD, but I don't know that anybody cared or even really noticed.
By the time that HDCD had died, almost all DAC chips came with their own built-in digital filters. A few had selectable algorithms, but just as with IC op-amps, I don't think that there are people at large semiconductor manufacturing companies sitting around doing listening tests to make the very best sounding filters (or op-amps).
"If you want it done right, do it yourself" is an interesting saying and there are now at least a dozen high-end companies creating their own digital filters. It seems clear that the only reason to do this would be if you really believed it sounded better than what was available off-the-shelf in a DAC chip (although I'm sure there are cynics who will say it all sounds the same and is just an excuse to charge more).
As always, strictly my own opinions and not necessarily those of my employer or Mother Theresa.
Charles, do you happen to have Lucinda Williams "Car Wheels On A Gravel Road"? If so, could you check it to see if it is real or fake HDCD?
I tried doing a search, no luck on that CD, but I found a discussion on HDCD that was quite amusing. See the link, even back then Kal was correcting misinformation.
And for another good laugh, here is a link to Corey Greenberg's review of Howard's book. All from 2005.
https://www.stereophile.com/reference/101
> > Charles, do you happen to have Lucinda Williams "Car Wheels On A Gravel Road"? If so, could you check it to see if it is real or fake HDCD? < <
Sorry, I like that album a lot but never bought it. It was released in 1998, so if it lights up the HDCD light, chances are that it did use an HDCD feature that can be decoded but that is just a guess. The PM A/D converter is still one of the best sounding units ever made. Any mastering engineer that cared enough to purchase and use it was clearly dedicated to sound quality. Right off the bat those are two good signs - a great A/D converter and a mastering engineer who cares about sound quality.
As noted in the previous post LLE was not meaningful for popular music. As to whether PE was used would be just a guess without running the ripped file through Foobar. The operator's manual states:
Operating Techniques:
Listening to both undecoded as well as decoded 16-bit playback is important, since HDCD
amplitude encoding effects such as Peak Extension limiting are more audible undecoded.
Limited Dynamic Range Pop or Rock
The best method to record highly compressed, limited dynamic range material depends
greatly on the results that are desired with undecoded playback.
Using Peak Extension allows very high average recording levels without "clipping" or gen-
erating "overs". This approach can be used to get the "hottest" possible sound (almost no
dynamics) during undecoded playback for air play, with decoding restoring normal dynam-
ics for home listening.
However, because Peak Extension limiting has an "easy over" curve that begins to affect
the signal at - 3 dBfs, it usually shouldn't be used with highly compressed source material
that will almost always be in the limiting curve, unless a highly limited or distorted sound
is desired during undecoded playback.
Typically, Peak Extension recordings do not have the "crunch" or "edge" produced by hard
clipping that is sometimes desired for certain types of rock material.
To get a hard "crunch" without any "easy over" limiting, turn Peak Extend off and adjust
DSPGAIN to a level just below full scale, usually - 0.1 dB. The digital input signal level can
then be adjusted using an external device such as a 24-bit editing workstation. This allows
as much clipping as desired without generating any "overs". To eliminate the need for an
external gain adjusting device, the Model Two can be put into a dual output mode with
digital output 2 set to HDCD_24, and digital output 1 set to HDCD_16, and offset -0.1 dB
relative to output 2 using OUT1OFS in the Levels Menu (see page 36). DSPGAIN can then
be adjusted to provide "crunch" on digital output 1 without generating any "overs". Digital
output 2 may then "over", but isn't used.
When a "dry" or "punchy" low level sound is desired with limited dynamic range material
that has little ambient information, Low Level Extension can be turned off.
That gives a "peek behind the curtains" as to the job of the mastering engineer. Clearly they are looking to create a "sound", not necessarily a direct transfer of the microphone signals to the disc.
I read your link to CG's review of Howard Ferstler's book. Pretty funny stuff! And have to admit that as a teenager in the '70s also had a Watts "Dust-Bug"... :-)
I still own the Watts Dust Bug, but haven't used it in 40 years. I wonder if it a collectable?
Around the days of the Watts I and a few friends tried the original Discwasher, and found it to create static. So, for many years I used a 3" Staticmaster, it had a horsehair brush and a strip of polonium. I still use the brush, but the polonium strip is outdated. Also use the AQ record brush.
You're probably right about Lucinda's CD actually using the HDCD settings. That album was recorded, scrapped, recorded again, and then she spent a lot of time adding and removing overdubs. I read that she was obsessed with getting it just right. All the effort paid off as she won Grammys, and lots of critical acclaim. I have found all of her albums to be well recorded. With the "Blessed" deluxe release the included second CD are the demos recorded in her kitchen on a portable Zoom recorder. And, they are surprisingly very listenable.
I've always admired your designs, but I live in Milwaukee, and I have never been aware of a dealer who sold them. So, I have never had an opportunity to hear any of your designs, particularly the amps would have been of interest. I was joking over at PS Audio that with the feedback on the latest firmware update, they should get the bronze busts ready for the Audio Hall Of Fame. I think there would be a place for you, if one existed.
I think everyone appreciates your contributions here.
Thank you!
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