0
$\begingroup$

When I hear a musical instrument in phone, the color of it sounds a bit different than its original 'live' sound. Why?

$\endgroup$
  • $\begingroup$ with "color" you mean some psychological quality of your personal perception, right? $\endgroup$ – Marcus Müller Nov 13 '16 at 12:05
  • 1
    $\begingroup$ and the short answer is: because your phone isn't live – the sounds it reproduces somewhat resemble the original perception, but obviously are very different. For example, take a big bass drum. You can feel it hit you in the stomach. Does your phone's speaker/headphones even have that amount of power? $\endgroup$ – Marcus Müller Nov 13 '16 at 12:06
  • $\begingroup$ @MarcusMüller I mean timbre. Especially the high frequencies sound different in phone. $\endgroup$ – Miroslav Sabo Nov 13 '16 at 12:09
  • 1
    $\begingroup$ And there you have answered your own questions! The higher frequencies aren't reproduced as your hearing expects them to be. A speaker, especially a small, cheap one, isn't a perfect reconstructor for any audio signal. And, to make things more complicated, a set of microphones, some kind of mixer, audio coder (with inherent psychoacoustic model), compression do not even perfectly record the original signal. Again, in short: the thing you hear from the phone is not the same as you hear live. That means there are differences :) $\endgroup$ – Marcus Müller Nov 13 '16 at 12:15
  • 1
    $\begingroup$ You can't make that generalization. A big bass drum will definitely sound totally different - and it's mainly producing low frequencies. So really, as I said, without knowing your recording system's and your playback system's exact behaviour, no other statement than "it's simply not the same signal, hence it sounds different" can be made. $\endgroup$ – Marcus Müller Nov 13 '16 at 12:32
1
$\begingroup$

Typical telephone codecs use a sampling frequency of 8kHz and a bandwidth of 7kHz. That means that your signal will get cut off at frequencies higher than 3.5kHz. That's ok for most speech but not sufficient for reproducing the timbre of most music instruments.

You'll likely fare reasonably well with instruments like recorders (which don't have a lot of overtones). The worst combination is high-pitched and overtone-rich, like violin, oboe, soprano sax. Also instruments with a full spectrum will sound different, like high hats, snares, gongs.

$\endgroup$
0
$\begingroup$

I am sure you know this, but your phone -including the isolated microphone and its recording mounting system- has its own equivalent recording transfer function $H_{phone}(\omega)$, which will be similar to your "hearing" transfer function $H_{head}(\omega)$.

The phone do his job in a relatively efficient way, the microphone is fairly good, and their speakers are also good. All of them limited, resting fidelity, but acceptable (we are in 2016 :)).

Which will really adds a difference is that, for the reproduction in your home, there is another transfer function, from the phone to your head, $H_{room}(\omega)$, which adds all the possible effects in your room or whatever place you are, thus distorting your original signal, and giving you a totally different perception of the sound.

IF you use headphones, in a silent room, and close your eyes (that step is important), you will feel again the sound as in the original event.

$\endgroup$
  • $\begingroup$ I promise, unless your headphones are cubic meters in size and actually large arrays of speakers, the sensation of a loud finale in e.g. a classical concert or a rock show can't be the same – simply a matter of amount of energy transferred into your body. But yes, eliminating everything that is not the reproduction of the original sound will help $\endgroup$ – Marcus Müller Nov 13 '16 at 14:44
  • $\begingroup$ Yeah, we are talking about more normal people like me, without major ear sensibility :) $\endgroup$ – Brethlosze Nov 13 '16 at 16:01
  • $\begingroup$ Expecting a headphone reproduction of music to be close to the original is kind of wishful thinking,even with very good headphones. Having headphones is a lot better than using cellphone speakers but there's absolutely zero possibility that the sound experienced will be the same as live. Don't get me wrong,I'm not saying it's going to be bad,it's really just different.As you noted,frequency responses aren't flat–and that's at least partly intentional,because that would actually not sound that good. So,audio folks typically don't aim for perfectly flat;they aim for"best perceived impression" $\endgroup$ – Marcus Müller Nov 13 '16 at 16:10
  • $\begingroup$ at least in reproduction. This doesn't apply to studio recording/playback equipment, where you record something that needs to be mixed and then reproduced later on – here, you'd typically aim for perfect reconstruction. That is definitely not the case for headphones, however, where it's psychologically nicer to emphasize certain frequencies. $\endgroup$ – Marcus Müller Nov 13 '16 at 16:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.