Upsampling DACS: Take the Pepsi Challenge

Gthirteen, you are more than welcome. Wonderful thing about this forum is that, with the collective knowledge and experience to draw upon, greater understanding will result in the truth. In my line of work, we use quite a bit of very sophisticated algorithm development. MUCH more sophisticated than that found in audio. But it is really hard to make digital theory easily digestible and therefore hard to bring it to a point where it makes sense to everybody. I think the author did a magnificent job in his explanation. Coming around full circle, you can see why Carl was right - digital has the infinite capability to produce more dynamic and "lifelike" quality of music than analog. But, as always, the science lags behind the enabling technology. Therefore, we will have to wait about 5 years, by my estimate, to begin to fully realize the promise of the CD. Biggest thing to remember is that the science of hearing and how the brain distinguishes sounds, transients, harmonics, etc. is really not well understood at all. Therefore, you and I hear (and "understand" music) differently. So it is catagorically incorrect to hold to one's opinion of perceived sound as an unassailable truth. It is THEIR truth but you and I might hear it much more differently than they did. Just take part in a speaker or interconnect cable double-blind study sometime. You will hear differences, sometimes, between various products. But can you really differentiate to the point whereby you say that "Number 1 is Nordost" and "Number 2 is Radio Shack"? Try it sometime. The results are going to amaze you and reveal new truths heretofor undiscovered. Therefor, you are the ultimate judge of the truth and you can only do that by comparing different equipment in your system. NEVER go by reputation. ONLY go by what pleases your ears. Music should just be equated with joy (not ego) whether you cry at an opera or bang your head with Kiss. I've done both and I am the better for it.

Gthirteen, you are more than welcome. Wonderful thing about this forum is that, with the collective knowledge and experience to draw upon, greater understanding will result in the truth. In my line of work, we use quite a bit of very sophisticated algorithm development. MUCH more sophisticated than that found in audio. But it is really hard to make digital theory easily digestible and therefore hard to bring it to a point where it makes sense to everybody. I think the author did a magnificent job in his explanation. Coming around full circle, you can see why Carl was right - digital has the infinite capability to produce more dynamic and "lifelike" quality of music than analog. But, as always, the science lags behind the enabling technology. Therefore, we will have to wait about 5 years, by my estimate, to begin to fully realize the promise of the CD. Biggest thing to remember is that the science of hearing and how the brain distinguishes sounds, transients, harmonics, etc. is really not well understood at all. Therefore, you and I hear (and "understand" music) differently. So it is catagorically incorrect to hold to one's opinion of perceived sound as an unassailable truth. It is THEIR truth but you and I might hear it much more differently than they did. Just take part in a speaker or interconnect cable double-blind study sometime. You will hear differences, sometimes, between various products. But can you really differentiate to the point whereby you say that "Number 1 is Nordost" and "Number 2 is Radio Shack"? Try it sometime. The results are going to amaze you and reveal new truths heretofor undiscovered. Therefor, you are the ultimate judge of the truth and you can only do that by comparing different equipment in your system. NEVER go by reputation. ONLY go by what pleases your ears. Music should just be equated with joy (not ego) whether you cry at an opera or bang your head with Kiss. I've done both and I am the better for it.

I have read many of the discussion boards here over the past year or so and I was especially interested in this particular discussion as well as the analog vs. digital discussion found in another emotionally-charged confluence of differing opinions. Below my preamble I have included a plagerized excerpt from a Soundstage review. I think it is very noticable that many people understand what they themselves have learned but have trouble conveying it to others with the same depth of understanding that they themselves enjoy. Whether they are right or wrong is irrelevant to them because they KNOW the gospel according to them. That being said I offer this thought for consideration: What sounds great to your ear might be mud to another's ear. It is the perception of the truth and not the truth that matters to us when listening. Do you hear some things for the first time when changing cables or do you just notice them for the first time because you have gone into a VERY active listening mode instead of a somewhat passive listening mode because you heard the source so many times before? I agree with Carl that digital is theoretically better at sound reproduction than vinyl, but keep in mind that CD technology is relatively new as music reproduction time lines go and it is really almost barbaric when compared to what will be heard from that technology within 10 years. Remember seeing the first Edison recordings that were made on the laquer tubes? Compare that to today's vinyl. Problem with vinyl is that, although it can still be optimized, it is a technology whose time has come and gone. It will be surpassed by the digital domain. I do disagree with Carl however in his observations about women, finding them overgeneralized and sophomoric (and yes I am a guy). There are differences between brain usage between women and men, to some degree, and women might be more attuned to certain areas of stimulation than men. However, I take exception with anyone who thinks that a man and woman can not be moved just as passionately by music or hear/appreciate the same dynamics. Just not true. Totally gender neutral. There are women who are just as scientifically curious as any man - ever hear of Madame Curie? I work with them every day and they are EE's and physicists. Depending on your system, you might not be able to tell the difference between those drums being played across the street for real or being played on a good recording through an optimized system. You know they are real because that kid is banging away, making msitakes, playing along to music he has playing, etc. You can tell from the acoustics right away. But if a really talented recording engineer went into that space, recorded that kid banging away with all the echo, attack, and decay - then you did an A/B listening test - I think you'd be hard pressed to tell the difference. The reason we know this is true is that it has been done before and more than not were fooled. But the music reproduction system would cost you upwards of $100k. As the digital technology advances, the breakthroughs in software and hardware will bring much of that front end cost down. The problem with digital vs. vinyl is that most people hear a pure "streaming" data set when listening to vinyl. It is infinite in its attack, transients, harmonics, etc. So vinyl picks up the harmonics and decay from transients better than digital - up till now. As you read through the information below, you will see why Carl is right in theory but the author teaches the lesson with great KNOWLEDGE and the ability to impart his knowledge to others. Here it is: Data-word length Some background. Here’s what a random 16-bit data word looks like for CD audio: 0011011000101110 There are 65,536 different values represented by the 16 digital bits (2 raised to the 16th power). Each of these values represents a voltage in the analog output signal. If the DAC IC outputs two volts maximum, then each different value for the 16 bits represents .0000305 of a volt (this isn’t a precise analysis, just a general conceptual overview). 0000000000000000 = zero volts 0000000000000001 = .0000305 volts 0000000000000010 = .0000610 volts 0000000000000011 = .0000915 volts 1111111111111111 = 2 volts If you increase the word length from 16 bits to 24 bits, the number of different voltages you can represent increases from 65,536 to 16,777,216 (2 raised to the 24th power). Each step in a 24-bit word would represent .00000006 volts, still using our 2-volt output model, compared to the .0000305 volts for each step in a 16-bit word (using the same 2-volt output example). You can see that the granularity in voltages representing the musical signal is incredibly fine when the data words are 24 bits long. Take an example where the audio signal wants to be .0000455 volts (still in our 2-volt example). With 16 bits available, software has to decide whether to make this voltage become .0000305 or .0000610 volts. There is no way with 16 bits to make a voltage that is .0000455 volts. But in the 24 bit world, you have an extra 256 different voltages available between .0000305 and .0000610 volts. One of them will be almost exactly .0000455 volts. Twenty-four bits is really higher in resolution than any consumer analog or digital audio products can achieve due to limitations in current electronic technology. Most digital products with claimed 24-bit performance lose probably three to four bits in the noise floor. But nevertheless, it is advantageous and comforting to have a digital standard that actually exceeds the capabilities of performance in consumer audio components. I’m not sure you would want to listen to music that requires all 24 bits to reproduce anyway; the loudest sounds would be as loud or louder than the loudest noise you ever heard in your life, well beyond the threshold of pain. The quietest sounds would require the total silence of an anechoic chamber to be able to hear them. What 24 bits brings to the table is headroom and footroom, which make digital audio more forgiving and easier to work with and offers an improvement in resolution even if limited to 20 or 21 bits of effective resolution. The circuitry in the D2D-1 creates a higher resolution digital audio bitstream by analyzing sequential groups of 16-bit data words and generating interpolated (best guess) 24-bit data words to replace the original 16-bit words. The process does have some margin for error, but it is vanishingly low. Keep in mind that in converting 16-bit audio to 24-bit audio does not increase the resolution of the reproduced audio. You can’t have more than 16 bits of resolution when you start with 16 bits of data, but the higher resolution digital bitstream can be more optimally transmitted and processed to make small improvements in sound quality.

Albert (my name is George, BTW) there is a real problem with vinyl. In another discussion thread on vinyl versus digital, there is a lot of REAL information from recording engineers regarding the inherent limitations of vinyl (mostly) and why it sounds better to some, worse to others. Basically, if I recall correctly, there seemed to be a consensus of opinion that there is a very vocal minority out there in the real world that prefer analog. (You might find the same type of minority out there that prefer tube over transistor). I don't know how good your hearing is, but I was blessed with perfect pitch and great hearing. I can hear things that others can't who are sitting right beside me. Now, this begs the question - do I hear these things because of genetically superior hearing, does my brain just process the information better, or was I actively listening to the music and the other person passively listening? As a follow-up question: is this gender based? I don't believe that it is gender based at all and enough real science has gone into the quest for that answer. The first part of our hearing to USUALLY suffer degredation is reception of the high frequency pitches. If you've ever operated an air gun, etc. without ear protection you might notice a ringing in your ears afterwards. Not good. Repetition of the same stress to your hearing over time will result in your loss of the ability to pick up certain high frequencies. The one thing that vinyl does is truncate the high frequencies because of the way they were rolled off or limited in the recording process. I've picked this up since the first time I listened to vinyl, more years ago than I care to admit. I personally like the higher frequencies to shine through on my music (this is why I prefer digital and I have done enough A/B testing on my own equipment to validate my opinion). But I also want a balance throughout my hearing range and hopefully some impact caused by subsonic frequency air displacement. So vinyl does not recreate the high frequencies that I look for, but it does the rest fairly well and it still offers constant streaming information to my brain. But it does not offer the wide dynamic range necessary to recreate a true "lifelike" representation or recreation of the musical event. Neither does digital - yet. It is very close. Everybody's hearing is different. Digital can reproduce those high frequencies that I am listening for while vinyl cannot. I seriously suspect that this is why some people get what is referred to as "CD fatigue." The higher frequencies are reproduced (above what is reproduced by vinyl) causing an adverse impact on the most sensitive frequency reception range of hearing. Suppose you have the best audio gear that money can buy - either analog or digital. I think analog offers the best state of the art at this point in time. Why? Analog is in its old age and is a very mature technology. Digital is in its infancy. As algorithms mature and newer hardware generations turn over, digital will eventually reach an even keel with analog in two to three years at the high end of equipment. But very quickly digital will surpass the vinyl recreation of what your brain perceives as a constant or unimpeded and fluid stream of information that we call music. Then we will have the trickle down effect into the mainstream or affordable digital equipment lines or models. As we learn more about digital reproduction of music and upsampling or oversampling (and how the brain processes these digital bit streams), the one thing that vinyl can NOT do is offer the incredible dynamic transients that digital can. And this will eventually make digital more "lifelike" or offer a more realistic recreation of a live musical event. But this is a double edged sword. Your amps and preamps may not be able to keep pace with the dynamics that the digital signal will bring forth. Speed will be the essence. In the end, right now, both methods of musical recreation can offer satisfaction to the listener. Depends on how your brain processes the input. The key is to find balance between the individual components that make up your system so that it is optimized for your listening preference. Right now vinyl is ahead by one run in the bottom of the ninth but digital's clean-up hitter is coming to the plate with nobody out and the bases loaded.

Carl, first of all if you're right about something you're right. Just because you were wrong on an issue (that Resolution Audio gentleman's explanation seems to bear that out) doesn't mean that you were wrong on everything. Secondly I was remiss in calling your remarks sophomoric. They were sophomoric and neanderthal. I haven't run into a total throwback like you for quite a while. And it has nothing to do with PC. It has to do with real world experience working with women physicists, educators, engineers, physicians, secretaries, medical personnel, research and tech "weenies", and many of them stereo lovers. From all economic strata. Having two grown girls that love listening to music on a high end stereo. Reading remarks like those from Plsl and his wife, above. Selling some equipment to a woman who "has it all" and just happens to listen to a high end stereo. You cannot make crass generalizations and expect to have them received as gospel when they are just pure prejudicial rubbish. Ever visit a private and predominately women's college or university? Ever look into dorm room after dorm room and see the stereo equipment in the private rooms? I'm not talking about boom boxes here. I'm talking about fine equipment. (BTW - my answer to that question is yes. About a hundred times). But as not all men are stereo lovers not all women are not stereo lovers. And YOU MISS THE POINT in the discussion. I WAS TALKING ABOUT THE REPRODUCTION OF THE LIVE MUSICAL EVENT OR AT LEAST THE CLOSEST REPRESENTATION OF THAT LIVE EVENT IN TWO CHANNEL STEREO; AND WHY DIGITAL WILL EVENTUALLY SURPASS ANALOG IN THE ABILITY TO RECREATE THE WIDE DYNAMIC TRANSIENTS NECESSARY TO MAKE THE BRAIN RECOGNIZE A MORE REALISTIC INTERPRETATION OF A RECORDED MUSICAL EVENT. Something that you were unable to do. Now tell me, you've forgotten how to read too, right? Where did I mention HT? To offer your jaundiced view of the world according to Carl and to espouse the notion that your bigotry is the truth is not just nonsense - it is lunacy. But I respect your right to be a bigot. You do it better than most.

Well said, Albert.

Carl - look for the thread about vinyl and live music. A lot of recording-types and musicians in on that one. There is a great explanation by a recording engineer or two about high reequency roll off in the vinyl recording process. Maybe something to do with RIAA? Anyway, read through the thirty or so posts and try to learn something for a change instead of letting your not insignificant bruised ego stand in the way of reaching an understanding of how the brain processes sound and how the process of recording sound onto vinyl is compromised. As to your juvenile comments regarding hearing - only true way to accurately compare or measure hearing is in a total anechoic chamber using standardized methods. Best place I know of is at an Eye and Ear Hospital. Yours better that mine? Doubt it. I don't really care. What's it going to be next? Dualing triodes at 10 paces? Grow up. Time to go play with my stereo.

Carl - look for the thread about vinyl and live music. A lot of recording-types and musicians in on that one. There is a great explanation by a recording engineer or two about high reequency roll off in the vinyl recording process. Maybe something to do with RIAA? Anyway, read through the thirty or so posts and try to learn something for a change instead of letting your not insignificant bruised ego stand in the way of reaching an understanding of how the brain processes sound and how the process of recording sound onto vinyl is compromised. As to your juvenile comments regarding hearing - only true way to accurately compare or measure hearing is in a total anechoic chamber using standardized methods. Best place I know of is at an Eye and Ear Hospital. Yours better that mine? Doubt it. I don't really care. What's it going to be next? Dualing triodes at 10 paces? Grow up. Time to go play with my stereo.

Carl you are a horse's behind, a point that you continue to prove. Oh, and BTW - come back when you get a real system. Maggies compared to Soundlab Ultimate 1's. Hardly. What a joke. You are boring. I'm out of here. Nothing to learn from you, that's for sure. How did those Barney tapes you are so famous for recording work out? Did those on 8 track tape, didn't you?