Question: What electronic stage is an audio power amplifier like the McIntosh MC-2300?

Context articles: LM386
Guitar amplifier
Power amplifier classes
Output transformerless
Audio power amplifier
RF power amplifier
McIntosh MC-2300
Bass amplifier
Modulation transformer
Linear amplifier

The LM386 is an integrated circuit containing a low voltage audio power amplifier.
 It is suitable for battery-powered devices such as radios, guitar amplifiers, and hobby electronics projects.
 The IC consists of an 8 pin dual in-line package (DIP-8) and can output 0.25 to 1 watts of power depending on the model using a 9-volt power supply.
A guitar amplifier (or guitar amp) is an electronic amplifier that strengthens the weak electrical signal from a pickup on an electric guitar, bass guitar, or acoustic guitar so that it can produce sound through one or more loudspeakers, which are typically housed in a wooden cabinet.
 A guitar amplifier may be a standalone wood or metal cabinet that contains only the power amplifier (and preamplifier) circuits, requiring the use of a separate speaker cabinet–or it may be a "combo" amplifier, which contains both the amplifier and one or more speakers in a wooden cabinet.
 There is a wide range of sizes and power ratings for guitar amplifiers, from small, lightweight "practice amplifiers" with a single 6" speaker to heavy combo amps with four 12" speakers and a powerful amplifier, which are loud enough to use in a nightclub or bar performance.
Power amplifier classes are, in electronics, a letter symbol applied to different types of power amplifier.
 The amplifier classes give a broad indication of the characteristics and performance of different types of amplifier.
 The classes are related to the time period that the active amplifier device is passing current, expressed as a fraction of the period of a signal waveform applied to the input.
 A class A amplifier is conducting all though the period of each signal; Class B only for one-half the input period, class C for much less than half the input period.
 A Class D amplifier operates its output device in a switching manner; the fraction of the time that the device is conducting is adjusted so a pulse width modulation output is obtained from the stage.
Output transformerless (OTL) is a term which describes a subset of vacuum tube audio power amplifier topologies, all of which omit an output transformer for the purpose of greater linearity and fidelity.
 Conventional vacuum tube amplifier designs rely upon an output transformer to couple the amplifier's output stage to the loudspeaker.
 Instead, OTLs use one of two primary methods for output stage coupling: direct coupling (DC) or capacitive coupling (AC).
An audio power amplifier (or power amp) is an electronic amplifier that strengthens low-power, inaudible electronic audio signals such as the signal from radio receiver or electric guitar pickup to a level that is strong enough for driving (or powering) loudspeakers or headphones.
 This includes both amplifiers used in home audio systems and musical instrument amplifiers like guitar amplifiers. Power amplifiers make the signal—whether it is recorded music, a live speech, live singing, an electric guitar or the mixed audio of an entire band through a sound reinforcement system—audible to listeners.
 It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers and speaker enclosures.
A radio frequency power amplifier (RF power amplifier) is a type of electronic amplifier that converts a low-power radio-frequency signal into a higher power signal.
 Typically, RF power amplifiers drive the antenna of a transmitter.
 Design goals often include gain, power output, bandwidth, power efficiency, linearity (low signal compression at rated output), input and output impedance matching, and heat dissipation.
The MC-2300 is a solid-state power amplifier which was built by the American high-end audio company McIntosh, and sold between the years 1971 and 1980.
 It can be utilized either as a 300-watt-per-channel stereo amp, or a 600-watt monoblock, and was rated by its manufacturer as being able to produce this amount of power continuously, with very little (less than 0.25%) distortion.
 McIntosh's ratings were conservative, however, because like many of their amplifiers, when bench-tested the MC-2300 has frequently been found to produce an even higher level of clean power.
A bass amplifier or "bass amp" is a musical instrument electronic device that uses electrical power to make lower-pitched instruments such as the bass guitar or double bass loud enough to be heard by the performers and audience.
 Bass amps typically consist of a preamplifier, tone controls, a power amplifier and one or more loudspeakers ("drivers") in a wooden cabinet.
 While bass amps share many features with the guitar amplifiers used for electric guitar, such as providing an amplifier with tone and volume controls and a carrying handle, they are distinct from other types of amplification systems, due to the particular challenges associated with low-frequency sound reproduction.
 This distinction affects the design of the loudspeakers, the size and design of the speaker cabinet and the design of the preamplifier and amplifier.
 Speaker cabinets for bass amps usually incorporate larger loudspeakers (e.g., 15" speakers are more common for bass than for electric guitar amps) or more speakers and larger cabinet sizes than those used for the amplification of other instruments.
 The loudspeakers themselves must also be sturdier to handle the higher power levels and they must be capable of reproducing very low pitches at high sound pressure levels.
A modulation transformer is an audio-frequency transformer that forms a major part of most AM transmitters.
 The primary winding of a modulation transformer is fed by an audio amplifier that has about 1/2 of the rated input power of the transmitter's final amplifier stage.
 The secondary winding is in series with the power supply of that final radio-frequency amplifier stage, thereby allowing the audio signal to lower and raise the instantaneous DC supply voltage of the power amplifier (PA) tube or transistor.
 Considering that the PA device is operated as a class-C amplifier, i.e. as a switch, the modulation transformer is responsible for the amplitude modulation (AM) of the transmitter.
A linear amplifier is an electronic circuit whose output is proportional to its input, but capable of delivering more power into a load.
 The term usually refers to a type of radio-frequency (RF) power amplifier, some of which have output power measured in kilowatts, and are used in amateur radio.
 Other types of linear amplifier are used in audio and laboratory equipment.