Analog vs. digital segment on PBS

Jlambrick...I was not aware that people who make CDs took such care. It does make it a lot easier for me to do the same thing on playback because I don't have to adjust gains for each CD.

Regarding the finding that music on CDs usually peaks very close to 0 dB, this is an operation called Normalization. The track or tracks are scanned, the absolute peak is logged and the appropriate amount of gain is applied to bring it up to the max. This can make a 16 bit CD use its maximum resolution to best effect since the music is usually recorded in 20 or 24 bit resolution. Unfortunately, fairly often excessive compression and unnatural EQ are also added in the mastering process.

Eldartford,

If you are listening to classical then it sounds like they are simply making the music fit on the CD as loud as possible without clipping the signal. The peak being close to the max 16 bits. That is normal procedure. There is nothing wrong with that.

Shadorne...The compression you talk about is common on pop recordings, but I have few of those. Mostly my recordings, LPs as well as CD, are classical, and there is no obvious compression. Some are quiet pieces for the most part, but somewhere there will be a peak that exercises all the bits.
Cliping of a digital signal is much worse than for an analog signal, but is much easier to avoid.

Eldartford.

That sound like a reasonable way to maximize the dynamic range CD is capable of. Too bad the recording people don't think about that when they produce them.

As quiet as CD's are, I don't see the point of pushing the limits and compressing them. Guess it's a way to put the music in your face, so even in a car or listening on a computer system, it jumps out at you.

What a waste when you have a nice system though.

Eldatford,

Actually the mastering engineer will compress (squash) the hell out of music first and then boost the average signal to usually within as little as 3 db of the maximum that a CD can digitally represent with 16 bits. This means the CD will sound loud as the dynamic range is now squashed to be contained within the top 10 db or less of the entire CD dynamic range format....i.e. the 96 db overall dynamic range is completely wasted at least 10 bits or more are all the same 1's practically throughout the entire CD!

This is great for a noisy car environment but in a quiet environment with a good system the music just sounds like what it is...squashed crap like you stepped in something...only good thing is it doesn't smell!!!

Albertporter...About the peak level recorded on a CD...I have a unit in my system (Behringer DEQ2496) that indicates the momentary recorded level, and logs the peak observed during the whole CD. I have adjusted gains in my system so as to maximize the signal as it goes through the DEQ2496, and to my surprise every CD I play hits within a few dB of clipping, but no clipping occurs. The recorded level of the CD is obviouly being carefully set (probably by trial and error) to make best use of the available dynamic range. This is similar to what one does when making a tape recording.

the final absurdity is the amount of money it would take to produce the "best regardless of price" playback equipment for each medium at the PRESENT LEVEL of technology; and then choose at least 100 listeners based on the best random selection process statistically possible. it just might not be worth the time, effort, and cost of such an experiment. some might STILL question the methodology and the meaningfulness of the results. so, like good scientists, the experiment would have to be repeated several times, perhaps even in differing cultures, latitudes, genetic factors, etc.
or you can take my word for it. records on my vpi aries sound good. the same recording on cd on my levinson redbook gear sounds very good also, just slightly different.
i spent more money on the digital equipment, but it is 10X more convenient to use, and is actually superior to the record in certain respects- a little less distortion, tighter, more controlled (but less expansive) bass. records stage better in some instances but not always. my vinyl copy of surrealistic pillow (jeff.airplane) is absolutely AWFUL.
NYPhilharmonic on Columbia-360 is wonderful, but the re-masters are thin and tasteless like diet-cottage cheese.
archiv cd's (trevor pinnock/vivaldi/handel/bach)-no sacd,hdcd, 4D, 20 bit, or 24 bit, sound almost as good as anything out there to my ears. check out the brandenburg concertos on archiv- the ONLY problem with this recording is there is (perhaps) too much information on the disc- Bach went crazy writing a separate part for almost everybody. you'll have no trouble hearing every note on a decent cd player, which might also give you an intense headache. i would LOVE the vinyl copy of this masterpiece as well, but it's torture sorting out all those woodwinds going their separate ways inside of various string parts. i really don't need to challenge my limited intelligence any more than i already have with the digital copy.
well, since i'm not an expert on this subject, my diatribe here amounts to little more than someone at a party who's had too much to drink and won't shut up. until i pass out on the sofa, which is right about now...

The results stated at the end of the testing, 20 brief samples/group, if I remember correctly, were: Engineer group correct 55% of the time; Musician group correct 53% of the time -- just slightly above chance, 50%. These percentages seem difficult to interpret or parse. They appeared to be summed for each of the two groups. The difficulty is determining what constituted a correct response in computing the percentages. If a sample were digital and one member of a pair responded digital and the other analog, how would this be counted? For instance: Is this a group miss because there was one correct and one incorrect, or is it two responses, one correct, the other incorrect? Was there a differential between members of each pair in percentages identified correctly (one engineer right 60% and the other 50% = 55% for the engineer group)? If one group member were wrong more than 50% of the time would this be an inverse correlation exceeding chance? (Wrong 65% of the time could be interpreted as being able to differentiate digital and analog even though misidentified; and would negatively affect the reported outcome "correct" statistics.)Was there a difference in identifying digital or analog material correctly?

My experience in reading about these issues is that technical matters about how the testing is done, such as some of the possible problems about the setup and administration of the testing on PBS identified in some of the posts, and how statistics are generated, organized and analyzed are often ignored in favor of a debate among the believers and doubters in each camp. If there are problems in any step of the procedures, the results cannot be meaningfully understood.

Given all of the issues identified in the procedure and the number of Rumsfeldian unknown unknowns can anything be concluded from this segment?

Albertporter, first let me say to your friend that is working with the JVC XRCD
project, that those CD's too me are some of the finest CD's made that will play in a standard CD player. I've said before that if all CD's were produced with such care the format would not get bashed so much. The list is long of things that can happen while recording and or mixing to affect the sound of the recording. I don't remember if they touched on the fact in the PBS segment that analog is very forgiving as far as the recorded level is concerned and that some of the warmth that is achieved from analog recording can be caused by the natural compression of the signal as it gets recorded. This happens when the level of the recorded material gets to hot for the tape to handle, but in digital when levels get to hot it is all or nothing. Digital is not a forgiving medium when mistakes are made. If you make it out of the studio with a good mix there are other things that can go wrong between finishing the mix and the actual release of a CD. One of the main things is the mastering of a project where for the last 10 yrs. or so the loudness wars have pretty much ruined the sound of many recordings, in every type of music. This is the phenomenon of everybody wanting their recording to be as loud or louder than the next persons. Loudness = compression = loss of dynamic range (no real difference between the loud and soft passages in the music), which could all lead to possible distortion on the CD itself, or even the distortion of the electronics being used in the playback of the CD.
These are just a few of the the things that must be taken into account to produce a great sounding recording, regardless of it being put on CD or vinyl. There is very long list of things that can go wrong, but I'd need to write a book to explain them.

Albert, do you think the typical CD "quality" we experience is due to the disc itself. I believe I hear a difference when I listen to CD-Rs from standard Redbook CDs using the EAC software, but it is not double blind. Any thoughts?
Tgrisham

In the case of the listening tests I did in New York, the digital master had much higher sampling rates than the consumer CD.

That's probably the biggest difference, or perhaps there are errors that the shiny disc creates while spinning, compared to tape against the playback head?

Another friend of mine was involved in the JVC XRCD project, he too is a recording engineer and audiophile. A few years ago at Stereophile, he and I were having a long conversation and he expressed his frustration that his digital masters sitting on the hard drive were incredibly good, but the VERY FIRST transfer to anywhere else, it moved toward digital nasty.

Note here, perhaps digital on hard drive is converted to analog at the studio for LP's production? If so, this might explain why DSD masters pressed to LP (often) sound better than Redbook.

Maybe this is a clock thing? Maybe the hard drive is more perfect and other formats are required to evolve the sound from that point on?

As for your tests with re-recording CD's, you are possibly getting error correction and that's what you hear. I've heard others say this is possible, many burn a "better" CD after software compares 100 times (or whatever).

You say you did not do double blind, no need, I'll take your word for the results.

I'm an advocate of relaxed listening over double blind. Long term allows you to relax, absorb and learn all at the same time. Double blind tests are like cramming for an exam the night before, instead of studying all semester :^).

I hope Tousana will contribute to this thread again.

They couldn't do Lp vs cd, everyone would have known which was which by the pops and crackles:)

I have read a few reviews of cd players lately where the reviewer states that the sound of the cd was close to if not equal to the sound of the vinyl version. I expect to hear that more frequently as time passes. I think that cd players are just starting to reach their potential and that there will be sonic improvements in cd players for a long time to come.

Albert, do you think the typical CD "quality" we experience is due to the disc itself. I believe I hear a difference when I listen to CD-Rs from standard Redbook CDs using the EAC software, but it is not double blind. Any thoughts?

Thank you Tousana. What great information in that story.

One of my good friends is a Grammy award winning classical musician, so I've been able to audition him live, versus digital, versus analog on several occasions.

During a recent visit to his home in New York I was able to compare several of his digital master tapes with the same material on Compact Disc.

The CD was a factory pressing, (not a special CDR which he also has), identical to ones released to the public. We listened to all on his high end system in a large dedicated sound room with his own personal equipment.

I am still shocked at how bad the CD's were compared to the master digital tape. The CD was a mere shadow of the original.

I have some analog safety's in my own personal collection (none are his work), with one that's absolutely a first generation (unmixed) master.

No doubt these best-of-best analog tapes are better than my LP's, even with my very high quality turntable and mere mid line tape playback machine.

Still, the difference between the two analog sounds is more dynamics and "you are there" rather than omission of quality and emotion.

In his system the analog was incredible as were some of the digital masters. BUT, the CD's as released to the public were just plan "nasty" compared to the original.

I would guess is the CD format itself is the problem. Do you agree or is it something that happens to the master when the record company gets done with it?

Opinion?

I have been a recording engineer for 24yrs. and use digital recording/Pro tools every day. So you might ask which I prefer, the answer good old 2" Analogue Tape. I have CD's, still listen to vinyl often and have never downloaded any music. If you could download full bandwidth files I might stop and think about it. I do prefer Analogue but these days it's usually more a matter of cost for most people. One reel of 2" tape $200-$250 and you get 15 minutes of record time and only 24 tracks of information. One album for a moderatly budgeted project 8 to 10 reels of tape. One 1 terabyte hard drive $400-$600 and depending on the system almost unlimited tracks. You could probably do at least 10 albums on the drive of that size. As for working in the digital domain it does not necessarily equate to being quicker or saving time. Also in my recent questioning, I find that alot of people just don't care, this is very unfortunate. The bottom line is I always try to record things to the highest possible level at my dispossal and within the clients budget. Just my thoughts on the matter. Just watched the PBS segment online, and it probably would have been better to have a nice sit down in a decent room, with some nice moderatly priced speakers to hear the differences.

Shadorne

Perhaps the whole thing was faked and the band who claimed they could not tell were all paid to do so (or more likely the music was all from the good sounding analog).

I think the test was performed exactly as portrayed on TV. Electroid took the words out of my mouth as to how things were likely done for the "test."

Another good point. CD's are often a lot worse than studio masters due to the mastering process where they are compressed horribly to sound "hot" or "loud" (no dynamics left after this process and very prevalent with pop music).

ABSOLUTELY correct, right in the bulls eye.

Add to that, lots of playback equipment is not happy at 0 DB (maxed out all the time). The chip sets are designed to swing and take advantage of digitals great dynamic range.........then the engineers "loudness wars" the format and destroy it's advantage.

Interresting but the test was between masters in a studio, not between the end products of CD and LP, which is what the average and above average listener would be using respectively. :D

I too found this disappointing . . .

Saturday 4am....... VIVA DVR!

I don't think they said what the final playback was from. They did an A/B on the fly "probably" from a digital platform. This would mean it was AAD vs DDD. Did they say what playback was from? Did I miss that? For true A/D comparison playback would have had to have been from the R/R recorder they used vs a digital platform .

ET

No one mentions that Pro Tools (the digital company) set up the test for PBS.

Interesting. Perhaps the whole thing was faked and the band who claimed they could not tell were all paid to do so (or more likely the music was all from the good sounding analog).

PBS relies very heavily on sponsorship....so you never know!

Sure, digital can sound great at "master" level, I've been fortunate enough to hear direct digital masters against the same release on CD.

Another good point. CD's are often a lot worse than studio masters due to the mastering process where they are compressed horribly to sound "hot" or "loud" (no dynamics left after this process and very prevalent with pop music).

Albert, more importantly Pro Tools is known in the recording arena as the software to use because of EASE not quality. Other digital editing/recording software is MUCH better but requires a brain to use. Many in my past field can't operate superior software that delivers quality.

No one mentions that Pro Tools (the digital company) set up the test for PBS.

Sure, digital can sound great at "master" level, I've been fortunate enough to hear direct digital masters against the same release on CD.

LP is not perfect either, but LP is the superior CONSUMER format for those willing to put in the time to make it right.

Perhaps when (and if) high def downloads become available we will finally have digital that's superior to LP.

Meanwhile it's still the 25 year old Redbook format with brick wall filters and digital nasty (or) downloads at no better resolution that what's already offered in the stores.

With Apple making hundreds of millions of dollars, selling crap downloads, we audiophiles will be lucky if truly high resolution downloads are ever offered. The recording companies see it as pearls before swine.

Interresting but the test was between masters in a studio, not between the end products of CD and LP, which is what the average and above average listener would be using respectively. :D

Using a different type of music may have helped to reveal differences. I've always found analog to be much better at reproducing ambient venue sounds, hall sounds, or 'air' vs CD's of the same recordings.

Of course there are many different degrees (sampling rates, word lengths) of digital. The test did not indicate (that I saw) what was being used and if it was what a consumer would get with a red book CD.

It was interesting and disappointing at the same time.

Interesting was the analog engineer saying that he could incorporate the same "effects" as the digital engineer. Then the digital engineer says - so what - "I can do it quicker and easier and you can't tell the difference". "I can even add effects to make it sound "analog"", which implies he hears a difference.

Disappoining was the short "verse" based testing and the non-blind nature of letting 2 people review at the same time. I can't pick out subtle differences in 10 to 20 second listens (tin ear, low res system?). Can you? Standing side by side and showing your choice visually has to exert some influence on the other listener.

I would have been a lot more anal about the test procedure.

Jim S.

The Wired Science findings only confirm what we know already...

That Analog is and has been the standard and digital has finally caught up but is NOT superior to analog.

well then, thank goodness the debate is finally over and done with... (btw, they both can, at times, sound miserable as well).
imho it was predominately more of a "money" issue than anything else.

Edo,

Thanks I missed it by ten minutes on TV last night. So I am glad you posted that link.

This was very well done.

=> Analog and Digital can both sound excellent!!!

In this case it seems they were indistinguishable in a short listening test...although they used headphones which increases the chance of hearing a difference)

The Wired Science findings only confirm what we know already (but some people still pretend that Analog is somehow inherently superior - it certainly has nostalgic appeal and may reflect most accurately the way historical music actually sounded when it was first issued).

In fact the main advantages of each format are well presented in the discussion. Glad to see they did not attack either format, as both have their merits.

just in case someone didn't post it by 12:45am PST the analog v digital segment video is at pbs.org
http://www.pbs.org/kcet/wiredscience/video/212-audio_files.html