Cheap and good-quality small audio set 01

The power circuit requires the transformer power to be around 30W to ensure sufficient power reserve and improve transient response. The secondary voltage output of the transformer
is about 15v, which rises to 21V after flowing. The filter capacitor C, l uses a 4700tiF electrolytic capacitor. A 0.33piF polyester capacitor is used in parallel
with C 2 to improve high frequency response and prevent self-excitation. The power supply is reduced to 15V after being stabilized by 78 1 5 three-terminal voltage. Using
C3 as loOrr-F can improve the power supply's ability to resist instantaneous pulse interference. The power circuit is shown in Figure 5-134.
    The power amplifier circuit and the input signal line adopt shielded
lines to improve the anti-interference ability against external electromagnetic fields.
The input coupling capacitor is a 1"F electrolytic capacitor
connected in parallel with a 0. U4 7 slI:F monolithic capacitor. The output capacitor
is a 470ruF electrolytic capacitor
connected in parallel with a 0.33VF polyester capacitor. 6 Since both the input and output coupling
capacitors have Smaller non-polar capacitors
are extremely beneficial for the transmission of high-frequency signals.
    The speaker is closed, with a volume of 10cm × 16cm × 26cm. The box is made of 15mm thick wood. After the asphalt is potted,
glue is used to paste an 8mm thick sponge on the inner wall. layer. The speakers use 4-inch ordinary speakers and 2-inch paper plate tweeters. They
are installed from front to back. The front plane is flat with the panel to avoid uneven mid-frequency response caused by front cavity effect and edge reflection. Frequency dividing
capacitor A Jiahui audio set is obtained by connecting two industrial Ot-ltF electrolytic capacitors in series.
    If the input coupling capacitor is changed to a CBB capacitor, the output capacitor is a tantalum electrolytic CBB capacitor, and the speaker is also
made of a high-fidelity speaker, the sound quality will be excellent. Directly to Hi-Fi.
    In this small audio set, L, the speakers are very ordinary and use closed speakers, so the low-frequency power is slightly insufficient, but
the mid- and high-frequency performance is quite good, especially suitable for enjoying light music and ethnic music. Compared with the currently popular heavy bass and super bass,
it has a different charm.