The 10 Best Mini Stereo Amplifiers
Special Honors
Denon PMA60-60 This class D amplifier pushes 50 watts per channel, so it isn't the most powerful, but what it lacks in oomph, it compensates with its pristine audio quality. You can route in via analog or digital, thanks to its built-in DAC, and you can also connect it to up to 3 Bluetooth devices at the same time — a feature which lends it well towards anyone who frequently hosts weekend shindigs in their house. Its digital audio processing system, known as Advanced AL32, can convert lower bit data to full 32-bits, improving dynamic range and low level resolution — and the result is noticeable. Compressed audio sounds worlds better thanks to this. Another clever design feature allows you to orient the device horizontally or vertically, and the OLED display will adjust accordingly. Those pressed for space will appreciate this greatly. Other useful features include the onboard headphone amp and a USB-B input. Overall, those with the money to spend may want to look here. denon.com
Editor's Notes
September 30, 2020:
For this latest update, we decided to focus solely on compact amplifiers that are widely used in homes and small workspaces, as there are many companies now dedicated to designing and building models specifically for this purpose. We therefore removed the Fiio E17K Alpen 2, Nobsound NS-08E, IFI Nano, and EarStudio ES100 headphone amplifiers, which are meant to accommodate private listening, and the Alpine KTP-445U, as this is reviewed on our dedicated car amplifier ranking.
In their place, we added the tiny Nobsound Mini for its affordability, versatility, and its impressive output for its size. We also added the Fosi Audio DA2120A, as while we already have the excellent Fosi BT20A on our list, this brings long-range Bluetooth connectivity, a liquid crystal display, and a remote control to the table, although it cannot compete with the latter in terms of output. Next up is the affordable yet highly functional Douk Audio G3, with its rugged and attractive brushed metal shell and simple, uncluttered layout. The third addition is the Loxjie A10, which is arguably the most impressive looking item in our ranking, with its steep, triangular profile and red aluminum housing. While this takes no prizes as far as features are concerned, it is ideal for those who are after a basic model and for whom excellent sound quality is a priority. Lastly, we included the eSynic M200 by virtue of the fact that it is intuitively designed and easy to operate while offering users an impressive five connectivity options, including USB-A, optical, coaxial, mini jack, and Bluetooth 5.0.
June 25, 2019:
On this update, we've curated a list mixed with amplifiers for headphones, home stereo systems, and cars. We chose the Alpine KTP-445U (#7) as a great option for anyone looking to install an amp in their vehicle, mostly due to its power and sound quality in relation to its low price.
We've deemed the IFI Nano (#2) as the champion of mini headphone amps on this list. Though it's costly, it is praised by audiophiles and casual listeners alike for reproducing sound with a clarity that brings out the best in musical recordings. It's also quite portable, which will be of great benefit to traveling musicians, producers, etc.
We added the Sabaj A4 to our list and decided it was worthy of our top spot. It's an incredibly well-rounded piece of equipment with a versatility that betrays its low price. Further, it has a subwoofer output — a rare occurrence in the world of mini stereo amps.
Live Loudly, Listen Louder
Unfortunately, the OEM versions built into vehicles, portable devices, and Blu-ray players often leave audiophiles begging for more hi-fidelity solutions.
The iconic picture of an aftermarket car stereo includes, for some people, a low-riding, 1960s-era Chevrolet, possibly equipped with hydraulics. But whether you're rolling in an antique muscle car, or commuting in your trustworthy Honda, few accessories make your trip as enjoyable as a quality sound system. And the way the market is, you could ask 100 different enthusiasts about the best audio equipment, and you'd likely receive 100 different answers.
There is no one-size-fits-all solution to audio system design. Numerous versions of countless models in different sizes aim to suit a very wide range of needs, and two situations are rarely alike. One of the first places to look for an upgrade to any setup, as well as the backbone of a custom package, amplifiers do the heavy lifting and are a major factor in ultimate sound quality. Unfortunately, the OEM versions built into vehicles, portable devices, and Blu-ray players often leave audiophiles begging for more hi-fidelity solutions.
The Importance Of Being Amplified
Fundamentally speaking, amps aren't so intimidating. They add additional power to a low-amplitude electrical impulse from a DVD player, car stereo head unit, digital-to-analog converter, turntable, 8-track player, or similar, which increases the output current to a strong enough level to move a cone. But moreso than many fields, audio engineering is beset with a flood of products, many of which are just barely different. This jungle can be tough to navigate, and at the end of the day, what sounds the best is usually the best choice. And it helps to have a basic understanding of the technical requirements of modern technology. After all, matching the right equipment can be the difference between bumping some fire bass in your car, and lighting your car on fire.
Peak capacities are only relevant at a certain point, and even the advertised RMS doesn't necessarily reflect the exact performance of a given model.
It's important to select an amp that supplies the right level of power for your specific system. Speakers with higher impedance ratings draw more power, thus calling for a larger amp. In car audio, many mid- and upper-range speakers operate at a nominal 4 to 8 ohms, while subwoofers generally run between 1 and 4 ohms. Overly large cones can overwork and damage the unit, while an overpowered and imperfectly wired amp can result in costly blowouts.
Aside from impedance, astronomical wattage claims also abound in the amplifier world. Peak capacities are only relevant at a certain point, and even the advertised RMS doesn't necessarily reflect the exact performance of a given model. So, it's important to analyze all levels of objective and subjective testimony regarding each contender.
Finally, the signal treatment portion of a sound system consists of two modules: amplifiers and preamplifiers, or preamps. The preamp performs a number of functions, such as receiving and managing various inputs and providing a main attenuator. It also adds a low level of power to any incoming signals that may be too weak for the main unit to process. The main circuit then takes the regulated and readable source and adds volume, equalization, and effects, preparing the new and improved signal for its eventual path to a large cone. Most options available in North America combine both of these stages in a single device, which makes installation easier and ensures that the components work together safely and effectively. Still, because of their potentially low profile and increased sound quality, some audiophiles do opt to use standalone preamps.
A Quick Class On Classes
At first glance, it looks like the comparison of the A, B, AB, and D classes is a complex one, full of nuance and specialized hardware. It is.
Classes are determined by the configuration of their circuitry, and the different types all have varying strengths and levels of efficiency. Less efficiency effectively means high excess heat dissipation, both a waste of energy as well as a danger to the component.
Further, they draw power dynamically, significantly reducing dangerous heat dissipation.
Widely regarded as the most true-to-signal design, the class A construction supplies constant power to the transistors responsible for amplification, whether or not a signal is currently present. Because there's no threshold level needed to trigger this power availability, the loudest, softest, and most intricate parts of the signal are readily powered and sent to speakers, with maximum clarity and minimal distortion. The drawback to that is a constant stream of wasted energy, which turns into residual heat, the mortal enemy of microscopic transistors.
Also known as push-pull setups, the class B schematic consists of twin transistors at the output end of each circuit. These transmit exact mirror images of each other's signal, thus balancing out the power draw, and making them roughly twice as efficient as their single-switch cousins. Further, they draw power dynamically, significantly reducing dangerous heat dissipation. The drawback is that as the two waveforms approach baseline, they pass through a dead zone as the transistors simultaneously switch on or off, resulting in crossover distortion that can cause harsh and loose-sounding tones. The creatively named AB type combines both, utilizing minimal, continuous power to a pair of transistors for quick and clean response. The baselines of these two inverted-signal switches are slightly offset, creating overlap near the center and preventing dropout as the waveforms balance.
Class D, on the other hand, is an entirely different beast. This somewhat newer consumer option triangulates and translates messy input signals into square wave patterns, at great benefit to efficiency and operating temperature. Due to past issues with sound quality, this particular design is still gaining traction, though its been refined and now receives praise for its incredibly low profile and high efficiency.
Every part of a custom setup plays an important role, and the amplifier itself has the power to make or (literally) break the rest of the system. While there are a ton of options to choose from, they continue to get more efficient and less expensive, all while sounding better.