Every time a 1/8 "audio connector is partially removed from the jack, it seems that the vocals are muffled, as if listening to the karaoke version. As far as I understand the connector device, this is not possible, however not only I noticed this effect.

What causes mute vocals with a partially extracted audio connector?

Closed due to the fact that off-topic participants αλεχολυτ , Alexey Shimansky , AK ♦ , Kromster , Vladimir Gamalyan Jan 28 '17 at 16:03 .

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  • Perhaps you have in the connector provided for the recording of sound (or headset) and you push it into the plug where only the audio stream is possible. From my experience, android headset (audio stream, recording stream), connect to the audio-only connector, we get a new sound :) without a voice !!! Even without processing, it is solved very simply, to pull out a little bit from the plug. Or a different plug where there is only an audio stream. - Denis Kotlyarov
  • @DenisKotlyarov yes, but it’s interesting at the expense of bringing such an effect - Vladimir Gamalyan
  • I don’t know, but you understand what a mixture of audio streams is and no one knows what (I don’t know exactly how the recording stream reacts to this) has unpredictable consequences. - Denis Kotlyarov
  • soundforlife.ru/problemy-s-fazoj most likely just the vocal goes to mono, everything else - in stereo - etki
  • 3
    The question does not apply to software and, according to the certificate , should be closed as off-topic. - αλεχολυτ

2 answers 2

When a connector starts to go out of the socket, most often its “common” (ground) contact is disconnected first. The remaining two contacts (left and right channels) are still connected:

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In this situation, both headphones continue to receive the signal, but now it is the difference between the left and right channels. Any signal that has the same phase in both channels starts to drown out.

Sound engineers, as a rule, place the vocals in the middle of the stereo panorama (both channels receive an identical signal), respectively, the difference between the channels for the vocals is zero, which causes the effect of muting the vocals.

    Curious question.

    A small disclaimer. Over the years, the entire institute course on the Theory of Automatic Regulation has flown out of my head as superfluous, so I will not vouch for the correctness of the logical constructions, and I will not give a concrete answer.

    To comment about "recording vocals in mono". Usually, vocals and guitar are always written in mono (look at external sound cards - they do not have a stereo output for guitar and vocals: LINE and MIC are there), but when it comes to the audio editor (cube, audio), there is always one of the steps to bring the signal to stereo, something like stereo fx. So it's probably not the case.

    I would put it on the fact that the LAFH / LFCH system is changing and the average frequency range is strongly cut where the main voice range is located. EMNIP, in (analog and early digital) phones, the width of a single telephone line is only about 300 Hz (usually at 20 Hz - 20 kHz headphones), so having muffled the mids as an equalizer, it’s just that the vocals are louder and quieter .

    Specific mechanics find it difficult to describe. A small air gap may appear, which acts as an additional resistance / resistor inserted in series with the headphones. The resistance of the headphones themselves is small, if you do not have studio headphones and amplifiers, there are only about ten ohms, and a small power of the amp itself [in the sound card]. Other things being equal, with increasing headphone resistance and constant power, the sound will be perceived quieter, which you observe. I can not understand where the irregularity of change for different frequencies comes from - in theory, the resistor should not produce such changes LAFC / LFCCH. I would venture to suggest that the change is uniform: the volume drops in the entire frequency range in the same way (for instruments), but it is “by ear” that the lower frequencies suffer where the main register of the human voice is located.

    • Vocals and guitar are written in mono, not because the input is one, but because it is point sources. Like most other tools. And whether there will be stereo there, it strongly depends on the genre, and if it does, it will be due to double tracks. - etki
    • @Etki There are usually two outputs, even on the cheapest zvukovuha for 500 rubles, but this does not affect the accuracy of the sources - and perhaps it will be even more important than the cost of the element base, so I agree. What do you think about the rest? - AK ♦
    • What I just half pulled out the plug of my headphones and heard a clear phase reversal in one of the channels. Where does he come from - I can not explain. - etki