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VenturaRV

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About VenturaRV

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  1. You had quite more success than me with "James Newton Howard & Friends" album. As you did, I wrote 'em and they allowed me to download... exactly the same dull, non-dynamics, obscure "thing" I already have downloaded. I did a new try and... a complete thick silence from them 'till this very moment. VenturaRV
  2. The name of the site is "Computer Audiophile"..., yes. The topics will often involve very technical discussions and arguments..., yes. It's not "all" about music..., yes and no. Music is just sound organized following cultural history, tradition and so forth. Because of this, it is logic to suppose an audiophile is, prior to it, a music lover. And a music lover that wants to hear at home the music (the organized sound) as faithful to reality as possible, the only "reason d'ètre" of High Fidelity (the second word is very important). If someone (no matter if a newcomer) remember us that maybe we're putting out of focus the first and last goal of our debates, perhaps he or she worths a little bit more attention from our part... and a small post of welcoming. VenturaRV
  3. Hi again, George. Please do not be mislead by Jud's comment about me. It comes from a personal disencounter of small or no consequence at all. Effectively, here are a good bunch of folks that have a lot of technical speech and knowledge (more than me), but it is not neccesary a bad thing, but normal in a site like this, as it would be in, say, a forum dedicated to cars. Of course you can ask anything you want to know or understand better, and many will help you, included Jud, whose opinions, despite his pathetic obsession against me, are usually ponderated and well informed (no sarcasm in this). Ask and comment, and enjoy a little bit of healthy discussion on a subject that obviously interest you. Cheers! [emoji4] VenturaRV
  4. Yes, your appreciations concerning verification of sampling rate (easy) and bit depth (difficult) are right, indeed. What worries me (because I suspect the same, sometimes even about myself) is your comment on how many buyers of hi-res audio will notice the difference. At the end of the day, that is an all important point: the ratio between those who really HEAR an improvement in hi-res, and those who just BELEAVE they hear such difference (or simply don't hear any difference at all). It is a bad symptom needing to analyze a music file to be sure if it is true hi-res or a fake... VenturaRV
  5. Is there a bit of sarcasm, or is it just my evil imagination? [emoji41] VenturaRV
  6. Welcome, George. Don't panic. You'll must see how things goes in the topic on cables (specially if they're digital and USB type). Just take our arguiinng with a grain or two of salt. Enjoy your love for music and sound (as all of us do, despite the appearances) and give your opinion or your impressions any time you like. Cheers. VenturaRV
  7. "Interpolation, upsampling, upscaling are all the same thing"... Three errors in one single stroke, and all three items implies quantification and, consequentely, their noise and errors. By the way: sound evolves in "time axis", true; but moving images evolves in, at least, THREE axis: two spatial (high. and wide) and one in time. VenturaRV
  8. No by no means. I just tried to show a contradiction: if computer generated square waves and single transient impulses were not acceptable in DACs evaluation, why equally computer generated sine waves would be "legitime" for the same purpose. I understand that a square wave has, in theory, an infinite odd order harmonic content, but the amplitude of each harmonic decreases 1/nf, being "n" the order (3, 5, 7,...) and "f" the fundamental frequency, so, in a digital system the highger order harmonics rapidly reach the LSB level, loosing any consequence. In the case of a pure sine wave, ideally, there are not harmonics at all, BUT as in the example you show, at the beguinning of the wave the level increases very fast (almost as a transient: the system cannot and must not make "predictions") and the unstability saw in the graphic is some sort of pre-ringing. My point was (and is): what is the proper method not subjective to. evaluate a DAC performance? Test CDs? No, if we do not accept them 'cause their signals have not taken into account the ADC conversion method. A wave generator passing first throw the ADC converter? No, because we will never know WHAT actually we are measuring (the only way to know with this method how the DAC acts will be to know how the ADC acts in the first place, but for this purpose we need a DAC, so we'll be moving into a circle). VenturaRV
  9. The "fact" is you (as many) do not understand properly sampling theorem. Sampling refers ONLY to samples of a signal that can take ANY REAL value before quantification. Quantification is a process that comes after sampling (and its consequences) has taken place. Now, the samples ONLY can take integer or rational values (the case of floating point), and always contains quantification noise, which is not a consequence of sampling process. If you doubt it, please refer to this paper in Google and see if you can read in it the word "quantification" at any place (the paper contains the math explanation of the theorem): [PDF] Sampling Theorem and its Importance. You're welcome. :-) Enviado desde mi G620S-L01 mediante Tapatalk
  10. I was sure that was gonna be your answer. Thanks a lot. :-) Sent from my G620S-L01 using Computer Audiophile mobile app
  11. About Shannon theorem or about digital treatment of serial images (and it upscaling to 4k resolution)? VenturaRV
  12. For the same reasons, we must assume as "illegal" the pure sine waves shown in the oscylloscope by oversampling DACs, since they are synthetic generated too. From this approach, we only can admit as a proper result at the end of the ADC > DAC chain sine, square waves and pulses generated by a loudspeaker in front of a measurement calibrated mike, as terms of comparison. VenturaRV
  13. As far as I know, Shannon theorem does apply to periodic functions, has nothing to do with digitazion (sampling is completely reversible, quantization is not), and cannot be applied to imagen. VenturaRV
  14. Well, that's not the case with computer generated square waves and sharp transient impulses in test CDs. Oversamplig filtered DACs ALWAYS show very visible pre and post ringing in the oscylloscope. Post ringing has, in transient response, minimal or null consequence since loudspeakers will vibrate after a sharp impulse aniway (unless you have an amp with an enormous damping factor). But PRE ringing (audible or not) will move tweeters out of their repose position BEFORE the signal arrives, in some sort of inversion of causality, or mysthic premonition ( ! ). ;-) VenturaRV
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