At the bar where I work, we usually play vinyl, but on busy nights we use a tablet with downloaded albums through Samsung Music. The tablet and sound system have been in use for about five or six years, and this problem affects only one album: a Nancy Sinatra compilation.
A few weeks ago, the vocals disappeared from one song while the instrumental remained completely normal. Since then, more tracks from the same album have developed the same issue. In one duet, Nancy's voice is missing but Lee Hazlewood's part plays normally. Roughly a third of the album is now affected, and once a song loses its vocals, they do not seem to return. Other albums sound fine, and the sound system otherwise appears to work normally.
What could cause vocals to vanish while leaving the instruments intact? Could this be a problem with the tablet, the music app, the audio files, or the way the sound system handles stereo and mono signals?
3 Answers
It is worth checking the music app for a karaoke, vocal-removal, balance, or accessibility setting, especially if the tablet recently changed configuration. However, because only selected tracks on one album are affected, an audio-channel or phase problem is more likely than a normal app setting.
The most likely explanation is that one stereo channel is missing or being combined incorrectly. Vocals are often centered in the stereo mix, so if the system loses a channel or sums two channels with opposite polarity, the centered vocal can cancel out while instruments panned to the sides remain audible. The duet makes sense too: one singer may be centered differently from the other.
Try the same files with headphones or another speaker system, and also play a different album through the bar’s setup. If the vocals return through headphones, the tablet and files are probably fine and the problem is somewhere in the speakers, cabling, mixer, or input connection.
Thanks, I’ll test the tablet’s built-in speakers and headphones after my shift. I was wondering why the problem seems to be spreading from one song to several, but I hadn’t considered a channel issue.
Check whether the sound system is receiving stereo and then converting it to mono. If the left and right signals are combined with one channel reversed in polarity, centered material—including vocals—can cancel almost completely. Reverb and other effects may still be audible because they are usually spread across the stereo field.
A bad cable, adapter, headphone jack, mixer input, or amplifier channel can cause this. Testing the album directly from headphones is useful, but also try a different cable or input and temporarily bypass the venue’s mixer if possible.
A surround setup could produce something similar if the center speaker or center channel has failed, since lead vocals are often routed there. Checking whether the system is stereo, mono, or surround should help narrow it down.
A failed speaker or amplifier channel could explain why this is only noticeable on certain songs. Some mixes place vocals strongly on one side, so losing that side would make the voice disappear while leaving much of the backing track intact.