Using op amp as power amplifier

Known as the "King of Op Amp", NE5532 is extremely famous in the audio industry. Because this op amp has the flavor of a tube,
it is commonly used by enthusiasts to make preamplifiers or power amplifier excitation stages. This article takes a different approach and uses NE5532 to make a power
amplifier.
    The conversion rate of NF:5532 reaches 9V/ps, which is higher than that of ordinary power amplifier integrated circuits. It eliminates transient intermodulation distortion and makes
the sound soft and delicate. The output impedance of this operational amplifier is as low as 0. 5n, and the power dissipation is as high as 800mW.
It is perfect for making low-power high-fidelity amplifiers.
    Because the output power of a single operational amplifier is too small to drive a low-impedance speaker, the two operational amplifiers of NE5532 are connected into
a BTI circuit form to double the output current and voltage amplitude. According to W=IzR. ． , theoretically increasing the output power of the op amp to four times, and this double push-pull DC balanced amplifier circuit can enable the op amp to still maintain very small distortion
when outputting the signal. The specific circuit is shown in Figure 5-.124
The working principle of 6 shown is the same as that of the general BTI_ circuit and will not be repeated here. In order to make
this circuit have a larger dynamic range, the operating voltage of the op amp is set to ±20V, and the output peak-to-peak voltage is ±18v. The power supply
is powered by a three-terminal voltage stabilizing integrated circuit that can improve sound quality. If conditions permit, it can be connected to an active servo power supply. In this way, the sound quality will be better and the
circuit components will be fewer. High-end products should be used as much as possible. The op amp is an authentic product from the American Signatus Company; Cl uses polypropylene
capacitors; C2 and C3 can use EI)NA electrolytic capacitors; the resistors all use 114W metal film resistors. The gain of the entire circuit
is set to 20d13.