Perhaps you were joking, and you made me smile, but there are no "analog" instruments (save perhaps analog synthesizers), because what could they be the analog of, or analogous to? They're the real thing, not an analog of something. You meant your acoustic accordion. It would be very confusing to call acoustic instruments analog, because even an electric accordion or electric guitar or digital synthesizer still uses analog electronics for amplification.
> An analog signal or analogue signal (see spelling differences) is any continuous signal representing some other quantity, i.e., analogous to another quantity. For example, in an analog audio signal, the instantaneous signal voltage varies continuously with the pressure of the sound waves.
> In contrast, a digital signal represents the original time-varying quantity as a sampled sequence of quantized values which imposes some bandwidth and dynamic range constraints on the representation.
> Analog devices are a combination of both analog machine and analog media
So, in common scientific use, this is fine. You are speaking of accordion analog, not analog accordion.
I think you are confusing sound, or vibration propagating as an acoustic wave through a medium such as air, which is what acoustic instruments produce, with signal, or the representation or analog of sound by changing levels of voltages, what, say, a microphone would produce, which is also electrically analog, or analog electronics. An accordion produces sound as air flows past vibrating reeds, producing sound acoustically. Acoustic instruments have no signal if they have no electronics. Thus, there is no accordion analog nor analog accordion scientifically or otherwise unless you consider a digital synthesizer's accordion-sound mode an accordion analog. If so, the C64razy digital accordion in the article is also an analog of an acoustic accordion and an accordion analog.
> In signal processing, a signal is a function that conveys information about a phenomenon.[1] Any quantity that can vary over space or time can be used as a signal to share messages between observers.
> In nature, signals can be actions done by an organism to alert other organisms, ranging from the release of plant chemicals to warn nearby plants of a predator, to sounds or motions made by animals to alert other animals of food.
Sounds are also signals. And using "analog" with accordion is not strict technical term, it's layman's term for "not digital". According to your usage, Commodordion is not digital, because it emits sounds, not numbers.
> I think you suffer from overpedantry and you are confusing electrical signal with just signal.
Tu quoque, ad hominem, and equivocation. "Signal" has multiple distinct meanings. You are conflating homonyms in equivocation, as well as attacking me personally while arguing, "you too!" Not all signal, by the definition you're conflating, is sound (such as semaphore, gesture, facial expression and even pheromonal response), and by the same vague definition, not all sound is signal (such as Berkeley's tree falling), not unless it is communication.
Context and semantics matter here. If we define sound as signal and vice versa, then there is no literal distinction between acoustic sound and analog signal, creating ambiguity and confusion. In the context of audio and sound, and from your own citation:
> in an analog audio signal, the instantaneous voltage of the signal varies continuously with the sound pressure... The term analog signal usually refers to electrical signals
A sound is also a a long, wide body of water that connects two other bodies of water, but it would be absurd and equivocating identical words of different meanings to claim that acoustic sound is also a body of water.
Perhaps you were joking, and you made me smile, but there are no "analog" instruments (save perhaps analog synthesizers), because what could they be the analog of, or analogous to? They're the real thing, not an analog of something. You meant your acoustic accordion. It would be very confusing to call acoustic instruments analog, because even an electric accordion or electric guitar or digital synthesizer still uses analog electronics for amplification.