A Digital Amplifier Buying Guide

Like if this guide is helpful
A Digital Amplifier Buying Guide

There is quite a bit of debate concerning digital amplifiers in the sound enthusiast arena. Some refer to digital amplifiers as class-D amplifiers, but the range of technologies signified by these two terms are somewhat of a misnomer. Digital amplifiers are designed to produce the highest possible quality sound through a high voltage system that is perfectly timed and aligned. Although digital amplifiers were once extremely expensive, leaps in technology allow music lovers to experience a more noise reduced, quality sound than ever before.

Online marketplaces such as eBay, offer an ample amount of options for users to find an amplifier to meet their needs. Before browsing through various digital amplifier listings, however, individuals should educate themselves on the digital amplifiers available. Issues such as digital vs. analogue, sound formats, and benefits of digital amps, are all essential aspects in determining which product is best suited for an individuals needs.

Elements of a Digital Amplifier

Due to the complicated definition of a truly digital amplifier, understanding what to look for in concern to such amplifiers is quite important. Educating oneself on how a digital amplifier works, helps individuals to narrow down search results and eliminate extra shopping time. Also, knowing what terminology is often used to describe a digital amplifier can be helpful as well. With the right amount of information, consumers can arm themselves with the knowledge needed to make an educated purchasing decision.

Receiving Digital Input

The first step that a digital amplifier takes in order to emit high quality sound, is to receive a digital input from a source. The term digital input is specifically important to remember. Amplifiers that are labelled as utilising analogue input, but claim to be digital amplifiers, emit sound very similar to normal analogue amplifiers. The reception of digital input is absolutely vital in the production of digital sound through a digital amplifier. The difference between analogue and digital input, is the basic differential between traditional amplifiers and digital amplifiers.

Digital Input Format

Usually, the signal received by the digital amplifier is a linear pulse code format. The format of the digital signal, however, is not restricted to this particular format. The essential part of digital conversion in an amplifier is the way the signal is delivered to the amplifier. Before ever committing to a purchase, make sure the amplifier is described as using digital input rather than analogue input. Without the difference between the two inputs, a class-D amplifier is no different that an AB-class amplifier.

PWM Format

One of the easiest ways to distinguish a truly digital amplifier from a more traditional amplifier, is the mention of PWM format. PWM stands for pulse width modulation format, which is the format most linear pulse codes and other signals are converted to. The PWM signal is then used by the pulse width modulator to create a high voltage signal. This signal is then filtered by the amplifier to accurately reproduce the original digital input. The benefit of such a process, when correctly accomplished, is a signal that is closely replicative of the original input audio.

The Sound Output of Digital Amplifiers

Once an individual understands the process of converting digital signal to PWM format, shopping for a digital amplifier should be a bit easier. The actual sound emitted from a digital amplifier takes place in the speaker terminals themselves, instead of in the amplifier. Sound output in a digital amplifier is normally synthesised completely through the speaker terminals. When speaker terminals are properly configured, the sound that is produced includes much less background and machine noise. Less noise often means a clearer, more accurate sound for listeners of a digital amplifier.

Class-D Amplifiers and Digital Amplifiers

Consumers are often surprised by the amount of class-D amplifiers that do not actually convert digital input to PWM signal emitted by a speaker terminal. Class-D amplifiers are labelled as such, with minimal regulation on which amplifiers are allowed to be so labelled. A truly digital amplifier of switching amplifier is designated as an electronic amplifier that powers every device through a binary switch. A truly digital amplifier should accept no analogue inputs. Also, a truly digital amplifier should have only: fully on and fully off settings, with no time spent moving between the two states of power.

The Challenges for Digital Amplifiers

The goal of a completely digital amplifier is to recreate audio input with no distortion through a unique pulse modulation strategy. Issues such as noise, voltage ripples, timing uncertainty, and more, all affect the output of sound. If a single issue arises during the conversion of the input to the output, the digital signal is changed. With so many issues that arise, it is no wonder that truly digital amplifiers are harder to find than more traditional, analogue based audio amplifiers. Online marketplaces such as eBay, however, offer enough listings to satisfy an audiophile's needs.

Digital Amplifier Uses

Due to the efficiency and minimal power consumption of digital amps, digital amplifiers are used throughout society in a variety of ways. Home theatre systems are often designed with digital amplifiers due to their minimal cost and mediocre performance needs. Digital amplifiers for home use, often are included in boxed home theatre sets that include everything one needs to set up a home audio system. Since these amplifiers convert digital audio without much feedback, digital options have cornered the home theatre market.

Other uses for digital amplifiers include: mobile phones and powered speakers. Since digital amplifiers strive to use only binary switches, such amps require very minimal power to operate. This minimal power consumption is ideal for mobile phones that need to conserve as much battery power as possible. Powered speakers also tend to be designed with a digital amplifier to properly convert audio signal.

Other Digital Amplifier Usage Options

Digital amplifiers are even used in some high end audio systems. Most audio system enthusiasts, however, tend to stick to more traditional analogue amplifier options. Digital amplifiers are even used in active subwoofers, as well as in some live sound equipment, due to the reduction in size and weight that digital options offer. With bass amplifiers also dabbling in digital options, those interested in utilising the slimmed down audio systems, have a range of choices from which to select.

Benefits of Digital Amplifiers

One of the most mentioned benefit that digital amplifiers provide is a smaller size and weight, as compared to more traditional amplifiers. Due to the usage of only binary switches, digital amplifiers do tend to be quite a bit smaller than other options. Reductions in size, however, is not the only benefit. Since digital amplifiers tend to be quite a bit more efficient, the power needed to operate a digital amplifier is drastically lower than most other amplifier options.

Digital amplifiers are also known for their ability to reduce not only power consumption, but power waste as well. Most digital amplifiers do not require large heat sinks, and sometimes require absolutely no heat sinks whatsoever. Due to the elimination or reduction of heat sinks, digital amplifiers also tend to be quite a bit more inexpensive as well. Since digital amplifiers tend to be both smaller and more cost effective, the popularity of such amplifiers has only increased over time.

Using eBay to Buy a Digital Amplifier

Purchasing a digital amplifier can be a confusing experience without the right knowledge. Even after the elements of a digital amplifier are understood, finding one tends to be quite difficult without the proper knowledge. With online marketplaces such as eBay, however, consumers are able to find the right product to suit their needs. To start searching, individuals must simply venture to the eBay home page, and type in a keyword such as digital amplifier into the search bar.

A single search query, however, many times results in hundreds if not thousands of results. In order to minimise shopping time, eBay offers an advanced search function that can be accessed through almost any page. Once a few products have been chosen, shoppers should utilise the advanced seller ratings offered through eBay. Whether you are concerned with shipping speed or item condition, there are ratings offered for almost every category. Shoppers can even choose between eBay authorised sellers, and local sellers which tend to offer quicker shipping options.


Digital amplifiers are designed to process digital inputs with minimal external noise and interference. Because of their use of binary switches, such amplifiers are often more inexpensive and smaller than more traditional options. Add in the ability to more efficiently use power, and the benefits of digital amplifiers are hard to ignore. Shopping for such an amplifier, however, tends to be quite difficult. Making sure to avoid a class-D amplifier that uses analogue inputs, is an intelligent strategy to avoid a less than stellar purchase.

Narrowing down the field to digital amplifiers that convert digital signal with minimal interruption, makes shopping at traditional stores much more difficult. With online marketplaces such as eBay, however, consumers are able to find the type of amplifier they want and need much more quickly. Once a digital amplifier is purchased it can be used for home entertainment use, live performance, and even for bass sound amplification.

Have something to share, create your own guide... Write a guide
Explore more guides