Colin Posted June 9, 2008 Share Posted June 9, 2008 CDs vs. Vinyl “At 1 kHz, 0 dB, distortion was 7%. "Wow, that's a lot of distortion," you say. You bet it is, but notice that it is nearly all second order. Also, the noise level contributes to this high number. At best, the noise is 70 dB below the signal, whereas with the CD test, it is more than 100 dB lower. http://www.hometheaterhifi.com/features/technical-topics/vinyl-vs.-cd---a-running-commentary_7.html It seems to me - and this is with some of the very best hi-fi components in the world - that one of the most significant reasons vinyl aficionados love the LP sound is that the distortion is very, very much like that in Pure Class A triode single-ended tube amplifiers. There is a lot of distortion, but it is virtually all second order (even-ordered), which is euphonic, meaning that it is pleasing to the ears.” So this is why I say to plug a CD into an analogue device! Now, they tell us, just when I have given up on CDs and am looking forward to digital media! Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted June 9, 2008 Share Posted June 9, 2008 Yeah, down with the CD its sucks Yeah!!! Yeah!!! Yeah!!! Yeah!!! Yeah!!!, (sorry my vinyl is skipping) Quote Link to comment Share on other sites More sharing options...
JJkizak Posted June 9, 2008 Share Posted June 9, 2008 You know, 3 db here, 3 db there and pretty soon you have 30 db. JJK Quote Link to comment Share on other sites More sharing options...
Islander Posted June 9, 2008 Share Posted June 9, 2008 I really liked this comment on that site: Another Advantage of LP written by Chabis ben Duvid , June 09, 2008 Play an LP enough times and you get to hear the other side playing backwards at the same time. This saves 50% of the needed listening time. Or, put another way, it allows you to enjoy twice as much music in the time you have. Quote Link to comment Share on other sites More sharing options...
pauln Posted June 9, 2008 Share Posted June 9, 2008 I wish that there was another word to use for the addition of frequencies to the original waveform other than harmonic "distortion". The majority of people think of distortion as a buzzy fuzzy sound. Harmonic distortion occurs when the waveform is altered by the operational element in the signal stage - stylus/cartridge (mechanical), gain stages (electrical), speakers (mechanical). The thing many mistakenly believe is that the harmonic distortion comes from adding the additional frequency components, but in reality what happens is the waveform is slightly deformed as if these frequency components were added. It's not really intuitive, but this is not a distinction without a difference. It's not that additional frequencies are generated by the element but that the deformation characteristic of the element is the same as if these additional frequencies were added. The shape of the deformation of third harmonic distortion on the upper and lower parts of the waveform are symmetric. Intuitively, many would guess this is the least offensive type of distortion because of the preservation of waveform symmetry. On the other hand, the second harmonic distortion is very offensive looking on the scope because it effects the upper and lower parts of the waveform assymmetrically. It makes the upper part more flatly rounded, but makes the lower part more pointy and extend further down. Intuitively - at first look most would see that and expect a severe impact on the sound. Yet, second harmonic distortion only adds a whole multiple of 2x to the frequency - an additional perfect octave above component, which all natural sounds already have. The octave is the most consonant interval to the ear. The second harmonic can be up to 10% before it becomes noticable to even an experienced critical music listener. Third harmonic distortion (3x fundamental freq) adds a fifth in the second octave above the funtamental, but its pitch departs from the tempered scale by +2 cents (very slightly sharp off key). The degree to which this error in pitch is disagreeable to the ear depends on the music and the melodic and harmonic aspects of music composition outside of the deliberate call for a fifth interval based harmony in the particular chord of the progression or phrase. Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 "The thing many mistakenly believe is that the harmonic distortion comes from adding the additional frequency components" Only because it does. Record something that is adding harmonic distortion to the signal. High pass it or notch out the fundamental and the additional frequency components are still there. Notching out the fundamental and measuring the harmonics that are left over are how some distortion meters work. " - an additional perfect octave above component, which all natural sounds already have." If so they would of course also be recorded and already be part of the playback. "The second harmonic can be up to 10% before it becomes noticable to even an experienced critical music listener." Distortion can be heard much lower then 10%. If it took 10% distortion to become audible then according to the above article there is no difference in sound between a CD and a record player since the record player has less then 10% distortion. Examples to follow.... Shawn Quote Link to comment Share on other sites More sharing options...
Colin Posted June 9, 2008 Author Share Posted June 9, 2008 thanks pauln, I understood the first half, and I got this: The second harmonic can be up to 10% before it becomes noticable to even an experienced critical music listener. that is the maximum amount of distortion I look for in a tube amp and now I know why Quote Link to comment Share on other sites More sharing options...
Colin Posted June 9, 2008 Author Share Posted June 9, 2008 second harmonic, Shawn, he said second harmonic distortion can be up to 10% Quote Link to comment Share on other sites More sharing options...
Mallette Posted June 9, 2008 Share Posted June 9, 2008 Woo, woo! Cat fight!!!! Dave Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 second harmonic, Shawn, he said second harmonic distortion can be up to 10% Yes, I know. Reference tone Tone with 10% distortion Tell me again how it takes a critical experienced listener to hear 10% distortion? This is plainly obvious on the junk speakers in my laptop with the AC blasting away in room. Shawn Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 New file to listen to. The tone-10% distortion file above was predominatly second order. This file is the same file but with a low pass filter applied at 2681hz and it is a fourth order filter. This is to remove the minor amounts of higher order harmonics in the earlier 10% file so the only harmonic distortion in the file is second order. 10% with lowpass Shawn Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 This is distortion spectra of first file... Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 Distortion of 10% with lowpass file. Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 Only because it does. Record something that is adding harmonic distortion to the signal. High pass it or notch out the fundamental and the additional frequency components are still there. Notching out the fundamental and measuring the harmonics that are left over are how some distortion meters work. As a demonstration of this this is the original 10% distortion file with a fourth order highpass filter at roughly 1800hz applied. This is removing the fundamental and leaving the add harmonic distortion in place. 10% with high pass filter removing the fundamental Shawn Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 9, 2008 Share Posted June 9, 2008 Distortion of above file, marker at 1000hz. Quote Link to comment Share on other sites More sharing options...
pauln Posted June 9, 2008 Share Posted June 9, 2008 The idea that the second, third etc harmonic distortions are not actually produced in the element, but that rather the effect on the output signal is the same as if these harmonics had been introduced is not my idea. It comes from the US Navy electronics training course NAVPERS 10087-A, 1955. I'm sure that the observation that up to 10% second harmonic distortion is difficult to discern comes from tests of listening to normal musical program material, not lone test tone sine waves which never appear in music. To me that seems like comparing two very close shades of paint stroked on a blank white canvas. Once the painting is completed and viewed, you really can't tell which one was actually used... Quote Link to comment Share on other sites More sharing options...
kev313 Posted June 9, 2008 Share Posted June 9, 2008 New file to listen to. The tone-10% distortion file above was predominatly second order. This file is the same file but with a low pass filter applied at 2681hz and it is a fourth order filter. This is to remove the minor amounts of higher order harmonics in the earlier 10% file so the only harmonic distortion in the file is second order. 10% with lowpass Shawn this one ROCKED!! Quote Link to comment Share on other sites More sharing options...
Colin Posted June 10, 2008 Author Share Posted June 10, 2008 thanks for the tones and the patterns Shawn fog, but I am not sure what I just learned, junk cone speakers have enormous quantities of TH distortation, which is why I think we are horn lovers here, but I don't know what is wrong with each of your tones, I only know they are different... how does this THD compare to CD jitter? Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted June 10, 2008 Share Posted June 10, 2008 I Like Good Music Quote Link to comment Share on other sites More sharing options...
sfogg Posted June 10, 2008 Share Posted June 10, 2008 "The idea that the second, third etc harmonic distortions are not actually produced in the element, but that rather the effect on the output signal is the same as if these harmonics had been introduced is not my idea. It comes from the US Navy electronics training course NAVPERS 10087-A, 1955." Already demonstrated that if the fundamental is removed the harmonics are still present. "'m sure that the observation that up to 10% second harmonic distortion is difficult to discern comes from tests of listening to normal musical program material, " You originally said 10% was barely audible to discriminating critical listeners. I posted two files demonstrating that 10% is plainly obvious. I have the same thing done with music too. Sorry but it was obvious there too. I used the test tones so I could easily verify distortion spectra and do the filtering examples. There are numerous discs out there with distortion tests like what I have posted. Everyone should try them sometime, hearing it live in your system is very different then just reading about it. Do you have a source or reference for the 10% number with some sort of testing to back it up? For example a few sources are quoted here:http://www.audioholics.com/education/acoustics-principles/human-hearing-distortion-audibility-part-3 as saying the percentage of audibility of distortion is up to an order of magnitude lower then you claim. It of course also varies by frequency. And again, if distortion below 10% wasn't audible then that means the original article talking about the differences in sound between a CD and vinyl is totally off base. The article said the second order harmonic distortion on the vinyl rig was euphonic, you are saying it is inaudible because it is below 10%. Is that really what you claim? FWIW the original article missed some other contributors, FR and interchannel phase response for example. They should also of course look at distortion over a wider frequency range too because the distortion level may vary wildly by frequency since it is a mechanical system. " test tone sine waves which never appear in music. " Music is of course made up of nothing but sine waves. Shawn Quote Link to comment Share on other sites More sharing options...
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