Company & Product Overview

Cambridge Audio’s first product way back in 1969 was an integrated amplifier. Cambridge Audio, as you might have guessed from the name, came from a group of young engineers/music lovers who met while studying at the famous UK university. They were the first company to use a toroidal power transformer in an integrated amp and they carry that tradition forward today. Cambridge Audio has always been all about making the best sound value for the money while creating products meant to last for decades. A pretty cool fun fact is that every Friday afternoon, they treat the UK team to a live concert which really keeps them connected to the importance music has in our lives.

Today’s review is on the Cambridge Audio CXA81, the top of the line integrated amp in their new CXA series. What is an integrated amp you might ask? Back in the early days of audio, many people bought a stereo receiver, which had an FM radio, a preamp (the part that lets you choose inputs and change the volume), and a power amp (the part that drives your speakers). If you remove the FM radio you have an integrated amp.

With streaming music becoming so popular, we have seen a huge increase in demand for integrated amps over receivers in that last several years. You simply add a music streamer to an amp and away you go. With most streamers and TV’s having some sort of digital output, we’ve seen a lot of integrated amps add DACs (digital to analog converters) to allow an easy way to improve your digital sound. The Cambridge Audio CXA81 has all of these features and a few more as you will learn about in this review.

Design & Build Quality

Cambridge continues the great look of the previous CX series with the tapered front panel giving the unit a look like it is floating on your shelf. The new series also moves to a Lunar Grey color similar to what you see in the Edge models. 

The easy to understand yet elegant front panel includes a large volume control, selection buttons for your sources, an A/B speaker selection button and a mini headphone jack. One thing that was slightly disappointing is the fact Cambridge removed tone controls from the new series. However the improvement in sound is nothing short of striking, so it seems they were going for pure performance with the upgraded models.

We were happy to see Cambridge continued the tradition of printing all of the rear labels both right side up and upside down. If you have ever leaned over a piece of gear trying to read labels upside down, you’ll really appreciate this additional printing on the rear, we sure do!

The way things fit together and feel on the Cambridge Audio CXA81 is pretty incredible for its price point. The volume knob has a very solid feel and the rear connections are top-shelf. We were especially impressed with the beefiness of the speaker binding posts. Cambridge Audio has always designed and engineered their gear in the UK then has it manufactured in the same facility they have used for almost 25 years rather than just farming it out to the low bidder. This philosophy has enabled them to have very consistent products over the last few decades. And speaking of decades, we think the build quality level on the Cambridge Audio CXA81 is so good, that is probably how long it will last!

Features & Technology

The connection set on the back of the Cambridge Audio CXA81 enables it to be the heart of a pretty large set of system components. Connection wise you’ll have 4 RCA analog audio inputs, 1 balanced audio input, 2 Toslink digital inputs, on coax digital input, a USB input, plus the amp now includes Bluetooth. You’ll get a set of preamp outputs and a subwoofer out. This gives you a great expansion option for adding a larger power amp later if needed. For control, you’ll still find the Cambridge proprietary connections with the addition of two sets of triggers, an external IR input connector, and an RS232 control connector. There is even a ground lift switch on the USB input in case that connection caused hum, very cool!

Taking a deeper dive into the ability of the digital connections will bring a smile to Hi-Res file lovers. Cambridge made a huge upgrade to the DAC’s in the new CXA series using an ESS Sabre ES9016K2M DAC which improved USB support up to 32-bit/384kHz and DSD256 quality. We had complained about this in the earlier model and boy did they ever improve it!  The HD Bluetooth aptX HD Bluetooth receiver is now built-in (with the old model it was an optional dongle) and it's capable of 24-bit/84kHz audio files.

On the more legacy digital inputs, the coax input will handle up to 24bit/192kHz and the two Toslink inputs will work on up to 96kHz. The new DAC not only enables support of much Hi-Res files but offers much better audio quality than the previous model.

To keep a clean layout and minimize button clutter on the front panel, they took an interesting approach to selecting sources. For example, most inputs just go directly to the button press, but they combined the analog one input which has two actual potential sources. The button changes color from red to blue with each press, red indicating balanced. They did the same thing with the USB and Bluetooth inputs. Red for USB and blue for Bluetooth. This did bite us the first time we tried the RCA input one, we forgot we had it on balanced, but once you get used to the color you’ll be fine.

You’ll notice the absence of a built-in phono preamp. We asked Cambridge about this and they felt someone getting an amplifier that sounded this good would likely want a better phono preamp than the typical built-in type. We wholeheartedly agree! Cambridge actually makes two great ones that are very reasonably priced, the Solo and Duo. The Solo will handle moving magnet type cartridges and the Duo will do both MM and MC.

Finally, we like the addition of a preamp output. This gives you the ability to add a larger power amp down the road and use the CXA81 as a preamp. Sitting next to the preamp outs is a single subwoofer out. This is handy for a smaller pair of bookshelf speakers that would naturally roll off if you wanted to add a sub, but there is no crossover built into the CXA81 to roll the bass out of the main speakers.

All of the inputs on the Cambridge Audio CXA81 give you lots of ways to connect to both current and legacy type audio components. The multitude of analog inputs gives you options for one or even two phono stages, a legacy FM tuner and even a cassette deck or reel-to-reel. The USB DAC is now perfect for using a laptop for your Hi-Res Audio files or ripped CD files. If your CD player and or streaming device has digital outs, you’ll more than likely get better sound by using the great DAC’s built into the CXA81. It will definitely improve the audio on a Sonos, Heos, Bluesound or anything similar.  

If your TV has Toslink digital out (and most do now), connecting it to one of the Toslink digital inputs will allow you to use your better stereo speakers for improved TV audio. Bluetooth HD is the icing on the cake. Recent statistics are showing Bluetooth is now the most popular audio source in most homes and we love the fact Cambridge has included it with as high a resolution as possible from Bluetooth HD!

The CXA80 model the CXA81 replaces quite frankly had an incredible sound for the money. From the first moment we heard it a few years ago, we fell in love with the way it just drew you into the music. We really wondered what Cambridge could do to improve the analog preamp and power amplifier section. The design of the CXA80, which had the goal of keeping down the number of components in the signal path, led to their Edge series. The Edge amp only has 14 components in the signal path. Cambridge Audio spent lots of time listening to new parts that had become available to tweak the sound of the CXA80 even further.

They wound up improving on most of the op-amps in the signal path and upgraded the capacitors used in the preamp and power amp sections of the Cambridge Audio CXA81. Whoever did all this listening and testing deserves a gold star as the improvements are not subtle but huge! If the CXA80 drew you into the music, the CXA81 grabs you by the collar and makes you sit down and listen!

As we said earlier, Cambridge Audio pioneered the use of toroidal transformers which is totally obvious right in the middle of the amp. Not only is it a massive transformer, but it has separate taps for the right and left channels giving you what is almost a dual mono design. And for under $1300, wow! Using this type of design improves stereo separation for great imaging.

You may look at the power rating on the CXA81 and think 80 watts per channel is not that much. Nothing could be further from the truth! With the massive power supply and its ability to drive just about any kind of load, the 80 watts of the CXA81 will make most speakers really come to life. Cambridge Audio, like many high-performance audio brands, focuses on having lots of current reserve and super clean power. We’ve found over the years that this approach always gives the best possible sound.

Being the audio geeks that we are, we had to pop the cover and peek inside at how the Cambridge Audio CXA81 was laid out. First, you can really see all of the support circuitry that surrounds the audio path to give the CXA81 its incredible sound. We even saw some circuit board isolation techniques we normally see on more expensive products.

Performance

In the world of audio, we’ve learned there are some products that grab your attention because they just flat out sound bad and another, smaller category of products that from the very first note make you smile and turn up the volume. The new Cambridge CXA81 is in the “make you smile” camp! From the first notes, we knew we had another extremely musical product from Cambridge on our hands.

We paired it up to start with on a set of B&W 704 tower speakers and used the Cambridge CXC CD transport as the source. There is something about great British sound that lets all of the emotions of the music through without adding any coloration that is just so much fun to listen to. When you add in how well it portrays dynamics, you are drawn further into the sound.

On tracks with a lot of deep bass information and impact, the CXA81 sailed through, controlling the 704’s about as well as anything we had heard. Flipping the coin, articulate, light bass details shined through as well.

One thing that really struck us was the clarity of the CXA81. Every single instrument is in its own space and very easy to pick out even when you have a few tracks of overdubbed guitars like on Fleetwood Mac’s Landslide. Flip over to a raucous Alanis Morrisette cut like Citizen of the Planet and the amp holds together on the complex sections with zero sense of strain.

Cambridge tells us they want their employees to be connected to the way music can move you. By providing free concerts to the entire company every Friday they keep this idea front and center. When you spend some time with the CXA81, you’ll see it is full of this DNA. It portrays music in a way that makes you want to find your favorite tracks and hear them again for what feels like the first time. We have always felt products that allowed all of those subtle emotional details the performers portray in a live concert to shine through, will stand the test of time and be extremely enjoyable for decades. Cambridge Audio, with the new CXA81, has put another model into that hallowed audio category!

Overall Recommendation

We feel the CXA81 can satisfy a wide range of music lovers. Please don’t write it off because it seems either a little too expensive for you or on the other hand too inexpensive to be really good. Anyone looking for an amplifier to be the heart of a great system in the $700-$2000 price range needs to give the Cambridge Audio CXA81 serious consideration. It is worth the extra step up if you are on the lower end and sounds simply incredible for $1300. Plus with its great array of inputs, you will likely never outgrow it. You’ll be able to drive most speakers with ease and you’ll get sound that makes you forget about the components and enjoy your music.