Analog speakers - the parameters and what they mean
All analog speakers are described by manufacturers using two basic quantitative parameters: power, expressed in watts (W) and impedance, specified in ohms (Ω). These parameters, however, say nothing about the frequency response of the speaker, which is of colossal importance for the sound quality. As a general rule, the larger the diameter of analogue speakers (or more precisely, their diaphragms), the better they are at reproducing low frequencies (including bass). Therefore, small analogue speakers, e.g. 15 mm MG15 or 28 mm YD30 are best suited for signalling tasks in mid and higher frequency bands (above several hundred hertz), while if you are looking for a speaker for a small radio or MP3 player based on Arduino - choose a slightly larger model YD78 or YD50.
Analog speakers for audio playback
For simple applications, where single tones or sequences of tones will be played, small analog speakers with foil diaphragm are perfect. In such cases, it will be most important to choose the appropriate speaker power and, consequently, dimensions (diameter and overall thickness). Speakers such as the 8-ohm YD36 with a power of 0.5 W and a diameter of 36 mm are surprisingly good at generating simple squeaks of varying intensity and frequency, although they are often used in small radios or toys, where they are able to clearly reproduce even music or speech. They will also work great in conjunction with sound modules (e.g. WAV/MP3 players) for Arduino, as well as in cooperation with minicomputers like Raspberry Pi. Be sure to check the maximum power that the output of a given module can deliver - you'll need to select a suitable amplifier if necessary.
Speakers that will rock at any party
For applications requiring more power we recommend large analog speakers A-165 from BLOW. In our store you will find two versions with the power of 200 W and impedances of 4 Ω and 8 Ω. Model A-165 has a very wide bandwidth - from bass (45 Hz) to high frequencies (6 kHz), which allows you to play music even without an additional subwoofer. Another very interesting solution are miniature analogue speakers Adafruit Bone Conductor Transducer, which transmit sound directly to the surface on which they are placed. In this way, a table, cabinet or everyday objects can become sources of surprisingly loud and pleasant sound. With this small transducer the phrase "jukebox" takes on a completely literal meaning!