The term 2.1 refers to a speaker arrangement, namely two mains speakers, left and right and one bass driver.
As with any other audio system, it will be as loud as the user sets it, subject to the maximum power outputs of the amplifiers. In almost all cases, the maximum volume will be far louder than is ever needed for a domestic setting.
No, it can output any type of audio.
Audio and Visual output is visual and audio
If I understand the question, you are trying to intertwine different functions. Like your ears, the audio input jack receives an audio source, while the audio output jack transmits outputs audio content - similar to your mouth. If you are trying to redirect the input audio directly to the audio output port you will need a "passthru" (aka monitor) function. -P2E
An audio frequency transformer is a transformer designed to operate in the range of frequencies audible to the average human. This range is generally accepted to be from 20 Hz to 20,000 Hz. The usual purpose of an audio transformer is to match impedances between circuit sections. For example: between a microphone and the input of an amplifier, (input transformer), or between the output of an amplifier and the loud speaker. (output transformer).
Audio
Audio output frequency is that range of frequencies that can be heard. For humans, that is generally considered to be the range of 20Hz to 20kHz.
Bose is known for qualities speakers. It would depend on which speakers you chose, but most if not all Bose speakers have the capabilities to be loud. It would also depend on how many speakers you bought, and the audio which is being output through the speakers.
That would be where you connect anything with a STEREO AUDIO OUTPUT.
Audio output.
It is audio output from the device to be connected to other equipment. Commonly color coded as White = Left channel and RED = Right channel.
A loud "squeal" or "screech" - also known as "feedback noise" - is usually only generated if there is an audio input device for an amplifier, for example a microphone, that is being used too close to an audio output device for the same amplifier, for example a speaker.
Speaker, headset, earbud.