Since the release of the first-ever commercial digital recordings back in 1971, avid listeners have been using their speakers when listening to digital audio. Fast forward to the present and almost all audio you listen to through your speakers is already digital despite the comeback of analog audio vinyl records.
This leaves many people wondering: are speakers analog or digital?
While speakers are typically connected to most digital audio devices, these are basically analog transducers. The speaker transducers turn analog audio signals or electrical energy to sound waves or mechanical energy. The digital audio should be converted into analog audio to drive speakers.
This article discusses speakers and their inherent analog nature.
Analog vs. Digital Audio
Analog audio is basically called such since the audio signal’s shape looks like or is analogous to the sound wave’s original patterns.
On the other hand, digital audio is recorded by taking the original sound wave’s samples at a particular rate. Vinyl records or cassette tapes are the best examples of analog mediums while MP3s and CDs are digital mediums.
How Sound Works in Relation to Speakers
Sounds move in pressure waves. Every time air particles are rarified and compressed fast enough, you will hear them as sound.
When the air pressure changes faster, you will also hear a higher frequency of that sound. When the speaker moves back and forth, this will push on air particles that cause changes in the air pressure and forms sound waves.
What are the Different Parts of Speakers?
Speakers are made up of the following different parts:
- The basket
- The dust cap and the cone, which are the parts responsible for moving air and producing sound
- The voice coil and the magnet, which are the parts that interact to turn electric energy into motion
- The top plate and pole
- The surround and the spider, also known as the suspension, which are the parts holding the cone in place and still lets them move at the same time
- The frame that mounts all the different parts together
How Speakers Work
A speaker works by turning electrical energy into mechanical energy or motion. This mechanical energy will compress the air and convert the motion into SPL or sound pressure level or sound energy. Once an electric current has been sent through the coil of wire, this will induce a magnetic field.
When it comes to speakers, the current is sent through a voice coil that generates an electric field that will then interact with the magnetic field of that permanent magnet that is located in the speaker.
Different charges will attract while like charges will repel each other. When the audio signal gets sent through the speaker’s voice coil, with the musical waveform moving up and down, the permanent magnet will then attract and repel the voice coil. It then causes the back-and-forth movement of the cone wherein the voice coil has been attached to. It is this back-and-forth motion that forms pressure waves in the air that humans perceive as sound.
What Makes the Best Speaker Different from a Good Speaker?
The best test of fidelity when it comes to speakers is how similar the pressure wave or waveform in the air is to the sound recording or electronic signals that have been sent to the amplifier.
A speaker can be considered superb if each frequency has an accurate reproduction to the listener without removing or adding any information.
There are a few factors that will determine the accuracy level of the listening experience, and these include the amount of distortion, the frequency response, and the dispersion or directionality of the speaker.
The Speaker Transducer or Driver
The speaker drivers or transducers are the most crucial element in monitor and loudspeaker design. The transducer is the component that is responsible for the conversion of electrical energy or audio signals into mechanical wave energy or sound waves.
To ensure the proper function of speaker drivers, the analog audio signal needs to pass through the conductive part of the design. This conductor is typically the voice coil, although there are also other kinds of speaker transducers that don’t necessarily rely on a voice coil.
The audio signal’s alternating current is what makes the speaker cone or diaphragm have a back-and-forth oscillation and generate sound waves that resemble the audio’s waveform. Digital audio isn’t a continuous alternating current and won’t drive a speaker driver.
The Role of DACs
Now, how come you can connect speakers to digital audio devices to effectively produce sounds if digital audio cannot drive speakers in the first place?
For a digital audio device and a speaker transducer to work well together, a DAC or digital-to-analog converter should be placed in line between the speaker and the audio device.
Based on their name, digital-to-analog converters are devices that can effectively convert a digital device’s digital audio signal into an analog signal which can properly drive the speakers.
The following are some of the devices where you can find these DACs:
- Audio interfaces
- Headphone jacks of different digital audio devices such as smartphones, tablets, laptops, MP3 players, CD players, and the like
- Digital mixing consoles
- Active speakers and power amplifiers
- Standalone adapters
Frequency Response and Its Importance
Frequency response refers to how loud a speaker’s output will be at varied frequencies. The usual frequency response test sends out the sweep of frequencies starting from the bass up to the mid and then up to the treble range to check if the speaker produces the same sound in all the different areas.
A speaker’s ideal frequency response is very flat, which means that the speaker should be at a similar level at low, high, and mid frequencies. The purpose of a flat frequency response is to make sure that the people who listen to the music will experience it in the exact way that it was meant to.
If the track sounds good and is well mastered with a flat response, it is almost always a guarantee that it will sound its best on all playback systems.