June 10, 2009 at Testing wav mp3 ogg
In student days, an inquiring mind haunted. The question "who is longer and thicker?" forced again and again to seek adventure on his own head.
Which is better? wav, mp3 or ogg? I think that an ordinary habrayuzer is able to independently prioritize. However, I am almost sure that there will be those who are not in the know because of which one format is better than the other, and the other is accordingly worse than the first. In this review I want to share the results of our modest experiments conducted by my good friends some time ago. As a result, not the latest software versions were used, but I think the overall picture is quite clear.
Experimental setup
Oscilloscope: ... 1 pc.
Pulse generator: ... 1 pc.
Personal computer: ... 1 pc.
Experiment goal
Show visually how the waveform changes after processing with various formats.
Experiment
The research was based on spectral analysis, i.e. frequency components in each of the presented sound files. Available software made it possible to simulate an ideal sawtooth signal with a frequency of 333 Hz and an amplitude of 500 mV, the spectral composition of which is favorable for analysis. These monstrous experiments were put on top of it ...
First, let's see what the ideal signals look like: The ideal sawtooth signal 333Hz 44100 The ideal 333 44500 wav high-frequency spectrum Now let's look at the real signal. The real signal is perfect, lost by Winamp. Real Sawtooth Signal 333Hz 44100 (WAV)
Real 333 44500 wav high-frequency spectrum
For those who are not very well oriented in the oscillograms or are not at all oriented, we note: the straighter the lines, the better. But the spectrograms are a little different: the more the graph is similar to the real WAV (you will not hear the ideal anywhere), the better.
We will consider the high-frequency region (13 - 23 kHz), since in the rest of the region there is nothing to consider, a very weak unevenness is observed. Further. We clamp the perfect and real signals from WAV to MP3 using Lame.dll and the CDEX program. MP3 Lame395mmx rel 44100 192kbps q = 0 CDEX mod1 parameters CDEX mod2 parameters CDEX mod3 parameters
Mod1 - selected from the recommendations of the manual for Panasonic CT-720. Frankly speaking, weak in both cases, a strong blockage (4 times) after 17 kHz, the spectrum is liquid.
Mod2 - to find out that there is q = 0, not q = 5. It affects very little, the spectrum changes slightly, but becomes more uniform, the blockage remains.
Mod3 - Selected because I like the sound at 255kbps, I decided to see why ... The result is obvious! Density and uniformity increase sharply, the blockage moves to the area after 20 kHz and halves. For ease of comparison, immediately after it again stands the spectrum of real WAV. The similarity is directly related! ..
You can also add that at 192kbps the uniformity grows and the obstruction shifts to 19.2kHz, and at 320kbps everything disappears altogether, the density is slightly lower.
Slides:
perfect signal, compressed MP3 Lame397b2 44100 192kbps q = 0 perfect signal, 333 44500 mod1 mp3 perfect signal, 333 44500 mod2 mp3 perfect signal, 333 44500 mod3 mp3 perfect 333 44 500 wav RF spectrum perfect signal, compressed MP3 Lame40A14 44100 192kbps q = 0 Real signal, 333 44500 mod1 mp3 Real signal, 333 44500 mod2 mp3 Real signal, 333 44500 mod3 mp3 The following are the results of testing the ogg format, with which the same manipulations have been done, so I suggest that you familiarize yourself with beautiful graphics, without any extra text. wav 333Hz 44100
Real 333 44500 wav HF spectrum OGG 4 128 OGG 6 196 Pay attention to how much OGG differs from WAV and the previously reviewed MP3 Spectrogram: Real 333 44500 OGG 192 Acknowledgments Many thanks to the user JIN: the hero of the soldering iron and the oscilloscope who performed the described experiments. Thank you, Eugene!
Which is better? wav, mp3 or ogg? I think that an ordinary habrayuzer is able to independently prioritize. However, I am almost sure that there will be those who are not in the know because of which one format is better than the other, and the other is accordingly worse than the first. In this review I want to share the results of our modest experiments conducted by my good friends some time ago. As a result, not the latest software versions were used, but I think the overall picture is quite clear.
Experimental setup
Oscilloscope: ... 1 pc.
Pulse generator: ... 1 pc.
Personal computer: ... 1 pc.
Experiment goal
Show visually how the waveform changes after processing with various formats.
Experiment
The research was based on spectral analysis, i.e. frequency components in each of the presented sound files. Available software made it possible to simulate an ideal sawtooth signal with a frequency of 333 Hz and an amplitude of 500 mV, the spectral composition of which is favorable for analysis. These monstrous experiments were put on top of it ...
First, let's see what the ideal signals look like: The ideal sawtooth signal 333Hz 44100 The ideal 333 44500 wav high-frequency spectrum Now let's look at the real signal. The real signal is perfect, lost by Winamp. Real Sawtooth Signal 333Hz 44100 (WAV)
Real 333 44500 wav high-frequency spectrum
For those who are not very well oriented in the oscillograms or are not at all oriented, we note: the straighter the lines, the better. But the spectrograms are a little different: the more the graph is similar to the real WAV (you will not hear the ideal anywhere), the better.
We will consider the high-frequency region (13 - 23 kHz), since in the rest of the region there is nothing to consider, a very weak unevenness is observed. Further. We clamp the perfect and real signals from WAV to MP3 using Lame.dll and the CDEX program. MP3 Lame395mmx rel 44100 192kbps q = 0 CDEX mod1 parameters CDEX mod2 parameters CDEX mod3 parameters
Mod1 - selected from the recommendations of the manual for Panasonic CT-720. Frankly speaking, weak in both cases, a strong blockage (4 times) after 17 kHz, the spectrum is liquid.
Mod2 - to find out that there is q = 0, not q = 5. It affects very little, the spectrum changes slightly, but becomes more uniform, the blockage remains.
Mod3 - Selected because I like the sound at 255kbps, I decided to see why ... The result is obvious! Density and uniformity increase sharply, the blockage moves to the area after 20 kHz and halves. For ease of comparison, immediately after it again stands the spectrum of real WAV. The similarity is directly related! ..
You can also add that at 192kbps the uniformity grows and the obstruction shifts to 19.2kHz, and at 320kbps everything disappears altogether, the density is slightly lower.
Slides:
perfect signal, compressed MP3 Lame397b2 44100 192kbps q = 0 perfect signal, 333 44500 mod1 mp3 perfect signal, 333 44500 mod2 mp3 perfect signal, 333 44500 mod3 mp3 perfect 333 44 500 wav RF spectrum perfect signal, compressed MP3 Lame40A14 44100 192kbps q = 0 Real signal, 333 44500 mod1 mp3 Real signal, 333 44500 mod2 mp3 Real signal, 333 44500 mod3 mp3 The following are the results of testing the ogg format, with which the same manipulations have been done, so I suggest that you familiarize yourself with beautiful graphics, without any extra text. wav 333Hz 44100
Real 333 44500 wav HF spectrum OGG 4 128 OGG 6 196 Pay attention to how much OGG differs from WAV and the previously reviewed MP3 Spectrogram: Real 333 44500 OGG 192 Acknowledgments Many thanks to the user JIN: the hero of the soldering iron and the oscilloscope who performed the described experiments. Thank you, Eugene!
