| 摘要 |
PROBLEM TO BE SOLVED: To increase the gain of a preamplifier circuit in a vacuum tube amplifier for musical instruments such as a guitar amplifier by increasing the number of signal amplification stages in series in the preamplifier circuit included in the amplifier itself without any of the increase in vacuum tubes or change of vacuum tubes and modification involving soldering.SOLUTION: The invention uses a channel in one side of a vacuum tube amplifier for musical instruments having multiple independent channels, changes the order in which a signal flows in a circuit by connecting a vacuum tube socket 11 for a composite tube and a preamplifier vacuum tube 12 to a device of the invention, uses an amplifier circuit part in the other unused channel side for signal amplification of the channel in the used side, and thereby increases the number of amplifier circuit stages in series. |
