The best stereo amplifier

Audio & Video Accessories

A stereo amplifier boosts audio signals to audible levels and replicates them as faithfully as possible. It is the heart of an audiophile-quality Hi-Fi and with the right combination of speakers, will sound notably better than any plug-and-play system.

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Which stereo amplifiers are best?

Hi-Fi technology is experiencing a resurgence, largely thanks to a renewed appreciation of the vinyl format and an increased interest in high-quality audio reproduction. The stereo amplifier is the beating heart of an audiophile-standard setup, which, when combined with an excellent set of speakers, is instrumental in achieving the best results from your Hi-Fi system. If you are looking for a comprehensive solution, the Cambridge Audio CXA81 combines power, quality and affordability in an attractive and well-designed package.

What to know before you buy a stereo amplifier

How much power do you need?

Power, in amplification terms, is basically how loud you can play music. The more powerful your amplifier, the more headroom you have before the signal starts to distort, and the size of your amp should correspond with the room size and, more importantly, speaker size. In practical terms, 20 watts of power is more than enough for most listening requirements and 100 watts of power is enough to disturb the people in the next block.

Signal-to-noise ratios

A signal-to-noise ratio is the measurement of background noise relative to the music. While most noise is almost imperceptible while music is playing, it still detracts from the overall quality of your Hi-Fi sound. The aim here is to hear more music and less noise, so when you are choosing your stereo amplifier, the higher the signal-to-noise ratio, the better. If you are listening to music through headphones, consider using a headphone amplifier to clean up your signal and boost its output.

Integrated amps and receivers vs. power amplifiers

Most of the amplifiers you see advertised online and in stores are integrated models. These units combine both the pre-amplifier and a power amplifier, complete with controls for volume and other parameters. A receiver further adds a tuner to the integrated amplifier. A power amplifier, on the other hand, has a separate power supply and works using much higher voltages, leaving no compromise with delicate low-voltage preamp circuitry and achieving better overall results.

What to look for in a quality stereo amplifier

There are some features to consider in choosing a quality stereo amplifier.

Connectivity

An amplifier must have the required connections to suit your needs. Most feature phono inputs for turntables and other Hi-Fi separates, but if you plan on connecting MP3 players or mobile devices, a 3.5 millimeter input can be invaluable. Many models also feature USB inputs for home theater interfaces and a wireless Bluetooth connection can revolutionize the way you interact with your stereo system.

Presentation

Gone are the days when a stereo consisted of a series of monolithic blocks, stacked in the corner of a living space. Modern stereo separates incorporate sleek designs into their manufacture, using interesting materials such as wood, brushed stainless steel or polished aluminum to embellish their facades. Some analog models feature exposed valves that gently glow as they process the signal. In short, a stereo amplifier needn’t be an unsightly addition to your living space.

Performance

Saving the most important feature for last, accuracy of sound reproduction determines how a good amplifier is measured and compared to other models. Stereo amplifiers are complex machines that must boost a relatively weak signal while maintaining the integrity of the source with as little distortion as possible. They must achieve this despite having amplified the signal several times from preamp to power amplifier to speaker, and the best amplifiers reproduce this signal most faithfully.

How much you can expect to spend on a stereo amplifier

While some brands make excellent quality amplifiers for as little as $350, midrange audiophile-quality products cost between $400-$900. At the professional end of the spectrum, expect to spend over $1,000, with some boutique models costing several times this amount.

Stereo amplifier FAQ

What are RMS and peak power ratings?

A. A stereo amplifier’s output is rated in one of two ways. Peak power refers to the amount of power an amplifier can generate in a short amount of time, regardless of its efficient working capabilities. A root mean square rating (RMS) is more useful, as it refers to how much power an amplifier can comfortably produce for prolonged periods, without distorting or overheating.

Which speakers do I use with my amp?

A. The output of your amplifier should ideally suit the impedance and sensitivity of your speakers. Impedance determines how difficult your speaker is to drive, whereas sensitivity measures how loud a speaker will sound, relative to the input. As a general rule, it’s better to connect an amplifier operating on a lower impedance to speakers with a higher impedance, rather than vice-versa.

What’s the best stereo amplifier to buy?

Top stereo amplifier

Cambridge Audio CXA81

Cambridge Audio CXA81

What you need to know: This British-made unit is notable for its exceptional build quality and its pinpoint accuracy that delivers across a wide sonic spectrum. 

What you’ll love: With 80 watts per channel, this powerhouse easily fills large spaces, but it also delivers highly detailed sound with very low levels of noise. It has multiple wired and wireless inputs to accommodate every device you can think of and handles both 8ohm and 4ohm speakers. 

What you should consider: Its front panel is very basic, with most features controlled via its comprehensive remote handset.

Where to buy: Sold by Amazon

Top stereo amplifier for the money

NAD D 3020 v2

NAD D 3020 v2

What you need to know: This compact model from the renowned Canada-based manufacturer packs plenty of punch into its pint-sized housing.

What you’ll love: The versatile NAD can be positioned horizontally or vertically and is the perfect complement to bookshelf speakers when upright. The Class-D amplifier features Bluetooth connectivity and a designated phono input for vinyl fans.

What you should consider: Its interesting design may not be for everybody and it might not blend well with other Hi-Fi separates.

Where to buy: Sold by Amazon

Worth checking out

Audiolab 6000A

Audiolab 6000A

What you need to know: This affordable audiophile-quality amplifier works seamlessly with both analog and digital sources.

What you’ll love: The Audiolab 6000A boasts several inputs, including a phono stage for vinyl lovers, a dedicated headphone amp for silent listening and Bluetooth connectivity. It has an impressive 100-watt output and a notably wide dynamic range.

What you should consider: This is not one of the more attractive models, but it might appeal to those who favor retro-looking gear.

Where to buy: Sold by Amazon

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Luke Mitchell writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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