Despite the advances, in the United States it seems that they have taken a step back. By increasing the use of transistor in household electronics, many valve manufacturing factories had to close their doors. Now, companies have retaken the manufacture of valves and are their "guilty" manufacturers of high-fidelity appliances, which in recent years have worked hard for the valve.
According to these musicians, the valves offer a much higher quality than transistors. For example, the valve gradually lowers the very charged signals, while the transistor cuts these signals at a stroke.
It seems that the voices of high-fidelity equipment manufacturers have finally achieved echo.