Audio amplifier with strange open loop, is it an oscillator?

Question

straight to the problem. Here is a picture of frequency response of my amplifier in the simulator (LTspice or Pspice both give same results).

Normally, in the open loop i see a phase of 90° which normally tends to increase. In this simulation I see a phase that starts at 180°.

Generally, an amplifier that does not oscillate, when the band touches zero, the phase is not more than 180 °. So, is this amplifier an oscillator, or is it the other way around?

EDIT: This is the frequency response bypassing the input capacitor.

Voltage Spike · Answer

No, but it might have a little bit of ripple in it at 10MHz, the ripple will be small at -10dB is equal to 0.316 of gain, so a 10mV input frequency at 10MHz would then be 3.16mV of ripple.

These 'bumps' in the amplifier frequency response are usually from parasitic values in the component or the feedback components.

You could put another pole in the feedback path to get a -40dB/decade instead of -20dB/decade

Audio amplifier with strange open loop, is it an oscillator?

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