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Default Distorted soubnd on LG Smart TV 42LW5500-ZE

El 02/05/2021 a las 4:08, Jeroni Paul escribió:
El jueves, 29 de abril de 2021 a las 13:19:13 UTC+2, Miguel Giménez escribió:
Good morning

I own a LG 42LW5500-ZE Smart TV about ten years old. It worked OK until
about two weeks ago, when the sound quality started to degrade and has
worsened from day to day. It sounds as a mix of saturation, crossover
distortion, box resonation and loudspeaker cone broken. I will open the
set this weekend, but before I would like to know if anybody has any
experience with this.

The sound make me remember class AB discrete amplifiers, when the bias
was not properly adjusted and the transition of one leg to the other was
not smooth, but the TV amplifier looks a class D one (NTP-7400L).

TIA

--
Saludos
Miguel Giménez


Hi Miguel, I hope you are all well.

As others said this sounds like a problem with the speakers. The coil is glued to the plastic membrane and is now loose from one side.
I have had luck fixing some of these speakers. Depending on the speaker construction it may be easier to pull the magnet or separate the membrane from the frame. Either way once you get access to the coil you can glue it back, I use two component adhesive. Make sure you glue it exactly at the original position. Once dry glue the magnet/membrane back, the magnet may need centering, for that I apply an audio signal while the glue is not dry and center it for a loud and clear sound.



Thank you, Jeroni. Glad to hear from you again, after
es.ciencia.electronica near defunction.

--
Saludos
Miguel Giménez