Rear acoustics — logbook Toyota Corolla 1999

Tired of the lack of normal sound. I bought Hertz ECX 165 back. I connected it to the output of the head unit. Until they played out (about 40 hours) they played disgustingly. Now the sound is back to normal. Feels like quality. After the Prolozhdi installed before, these speakers are COSMOS!
I put bits of bitoplast under the speakers