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Posts by stv014

It depends on how good the implementation of the sample rate conversion is. As these tests in an older thread show, it is possible to achieve very high quality 44.1 to 96 kHz conversion (200 dB rejection of aliasing, and negligible frequency response error up to 20.5 kHz) with about 1.6% average CPU usage on an Intel i3-2120 CPU, and the program used was not even very optimized. Given that converting to 48 kHz is computationally cheaper, and for audible transparency lower...
 In other news: do not compress documents to zip or similar formats. When decompressed, the text will have missing parts and more grammar and spelling errors.
The distortion of dynamic speakers and headphones depends significantly on the frequency and level of the signal. Generally, the distortion is higher at lower frequency and/or higher SPL. Therefore, the woofer may easily have a few % of distortion while playing loud bass, but at the same time it is only tenths of a percent for the midrange speaker, and maybe even less for the tweeter. It also depends on the SPL, as already mentioned. Good headphones have lower distortion...
Parallel capacitance would have to be fairly high to make an audible difference, and even then if it is the same on both channels, it would just add treble roll-off. Additionally, most amplifiers that use negative feedback do not like driving capacitors, and if the capacitance is too high, they may become unstable (oscillate).   One simple trick to change the sound with passive components in a connector would be to add ground resistance, which results in crosstalk with...
No dither is not always necessarily a problem, especially compared to simple non-shaped dither. While it obviously makes a major difference with artificial test signals, complex music that is never very quiet (e.g. during a long fade-out to silence at the end) may have enough entropy in the least significant bits that it essentially becomes "self-dithered". Basic dithering always adds a few dB of extra noise floor (which can make an audible difference at 8-bit resolution),...
 That is a different issue, though, the OP was apparently only interested in knowing if lossless compression is really lossless (i.e. bit perfect), which it obviously is, barring software bugs or hardware failures. The encoding/decoding libraries for these formats are also fairly old and well debugged. Player software normally will not implement decoding from scratch, but use the existing and freely available libraries. The FLAC encoder even validates the compressed stream...
At a higher frequency resolution, the noise looks more like a number of tones, but I do not know what it exactly is (other than it being probably some sort of interference in the recording). It seems to be pairs of tones about 25 Hz apart, which may or may not mean it is related to PAL TVs or some other "noisy" equipment.    The second graph shows only the lowest frequency tone with even more zoom. As its frequency is ~15624.5 Hz, it is very close to the PAL horizontal...
 The files are made because there are people who buy them since they believe the format makes a useful difference. That is just how the free market works. The files can also be really (audibly) different for other reasons, such as mastering. Sell a heavily compressed and clipped "loud" CD format version for the masses, and a non-distorted high resolution one at a higher price for audiophiles. In this case, the latter is indeed better, but for purely marketing reasons, and...
 Ideally, the 44.1/16 version should be converted back to the original format for the purpose of the comparison. This obviously cannot recover the lost information, but it prevents a false positive result due to hardware or software issues. For example, the DAC may output an audible click when switching between 44.1 and 96 kHz sample rate, which gives away the identity of X and Y in the test.
I do not think it is noise shaping, and that would have a less narrow peak at a higher frequency. It is most likely to be some kind of interference. For example, a 15.6-15.7 kHz signal may come from the PAL/NTSC horizontal frequency of an old analog CRT television or monitor (younger people can often hear this near such devices as an annoying high pitched tone). It would be easier to analyze if you uploaded a short section of the sample as a WAV or FLAC file.
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