We recently reviewed the Cambridge Audio CXA81 Integrated Stereo Amplifier and it was probably the most entertaining amp we had a chance to listen to this year. I hooked it up to a pair of Kef LS50s, a pair of speakers that needs quality amplification to shine, and I was astonished by the control of dynamics along with the overall clarity.
The CXA81 is part of Cambridge Audio’s CX Series 2, the latest edition of their highly-rated mid-level hi-fi components. In a way, it’s sort of a throwback, with very few bells and whistles.
Unlike its predecessor, the CXA80, it has no tone or balance controls on the front, it also does away with the front 3.5mm Aux Input. It harkens back to the days when high-end manufacturers shied away from such things for fear of degrading the signal.
I reviewed the CXA60 from the original CX Series here on the site, and it quickly became a favorite of mine due to its ability to enliven even the most clinical of speakers. It was so engaging; I found myself listening to it with a pair of Q Acoustics 3020i Bookshelf Speakers for hours on end.
The new CX Series Integrated Amplifiers improve upon the originals with new ESS Sabre ES9016K2M DAC chips replacing the old 24/192 Wolfson DACs. With the new chip, their USB inputs now support 32bit/384kHz PCM and DSD256. They also have built-in aptX HD Bluetooth receivers for “high-resolution” wireless audio.
The overall design of the CX Series 2 is quite similar to the first CX Series, adopting the same beautiful “floating chassis” design. This time around, they used a matte grey finish on the front panel instead of the brushed aluminum look they used before. I think the new finish is more up to date, so I dig it.
The front panel is also cleaner than before due to the removal of the tone controls and 3.5mm aux input. I don’t think many will miss the aux input, but the omission of tone controls may be a deal-breaker for some. The 3.5mm headphone out remains.
What It Does: The CXA81, with its Class AB amp section, drives speakers down to 4 Ohms with 120W per channel RMS, and 80W per channel RMS into 8 Ohms. That means it has the gusto needed to drive inefficient speakers like the Kef LS50 to their full potential. (I loved the synergy of that combination, by the way, more on that later)
It also has the best sounding Bluetooth section I’ve ever heard on an integrated amp, blowing away the Bluetooth on my Audiolab 6000A reference unit. When I listened to aptX HD on the CXA81, it was the first time I was able to listen to Bluetooth on an amp without missing the wires.
When I compared Bluetooth to the sound produced by the USB input, the USB was more spacious and had more depth, but the difference wasn’t immediately evident. Usually, I can tell the difference right way, but I had to do a quick A-B to hear it this time.
The CXA81 is plug and play. If you listen to many different genres of music and just want it all to sound good, no muss, no fuss, then this is the amp for you.
It has tons of inputs and outputs, so it’s very flexible…On the analog side, you have 1 set of balanced XLR, plus 4 RCA. On the digital side, there’s 1 S/PDIF coaxial, 2 TOSLINK optical, and 1 USB audio. Outputs include a 3.5mm headphone out, Preamp Out, and Subwoofer Out.
The CXA81 is Roon Tested, which means the manufacturer has worked with Roon to ensure it can, amongst other things, receive a bit-perfect signal from the software, and do some other DSP tricks for better sound quality. All of this worked without a hitch.
What It Doesn’t Do: There’s not a lot of fine-tuning here. There’s no screen, no menus, no tone controls. No DAC filter settings. (questionable if they’re needed anyway) What you hear is what you get. If you’re the type who likes to tinker, you may not be happy with this amp.
Features at a glance:
80-watts per channel with Class AB amplification for detailed and powerful audio performance
Separate, symmetrical left and right channels are carefully engineered to deliver incredible sound-staging
Balanced XLR inputs for low noise interference
High-Quality DAC – Connect digital sources directly via TOSLINK and Coaxial
USB Audio Input accepting up to 32bit/384kHz & DSD 256 digital files from Mac or PC
Sound: After listening to a lot of Cambridge Audio gear over the years, I expected the CXA81 to have a lively, rhythm-driven sound, and I wasn’t disappointed. I hooked up the Kef LS50s and cued up some music on my LG V40, playing Tidal over aptX HD Bluetooth.
I fully expected to be underwhelmed with Bluetooth over the Kef speakers because they’re so revealing. They tend to accentuate imperfections in the signal, so I expected things to be a mess. Boy, was I wrong.
I started with my “Test Tracks” playlist, planning just to get a feel for the amp, and about two hours later, I was still sitting there with a goofy smile on my face.
No matter what type of music I put on, the CXA81 took full command of the LS50s, with deep firm bass and a wide-open sound that enveloped my listening position. This is the type of sound I heard in the original CX Series, so no surprise there, but in Series 2, I also heard more refinement, especially in the treble and mids.
Listening to Daft Punk’s “Touch,” I was amazed at the instrument separation and clarity of the vocals. The CXA81 drove the beat through the LS50 speakers with fantastic authority.
When I switched over to the USB input, playing Roon from my HP Envy Laptop, I was even more impressed. The soundstage became massive, with crazy amounts of air between instruments. The sound was upfront, putting me in the front seat of an intimate club.
When I listened to “Let’s Face The Music And Dance” by Jeff Goldblum & the Mildred Snitzer Orchestra, Sharon Van Etten’s voice sounded like she was right in front of me, with the Bass, Piano, and Horns arranged neatly behind her to the left and right. The transparency was terrific.
Conclusion: I can’t get enough of the CXA81 tuning. The more I listen to it, the more I fall in love. The warm, open character just works no matter what music is played. That being said, if you don’t like the sound, there’s not much you can do about it since there aren’t any tone controls and no filter settings for the DAC.
If you’re using software like Roon or Audirvana, then you can make some adjustments there, but if you’re a control freak, it’s something to think about. For me, it’s not a dealbreaker because I don’t use EQ or tone controls as a general rule.
I was also super impressed with the Bluetooth. Usually, when I use it on an Integrated Amp, it’s for a quick listening session where I’m just playing music in the background. But with the CXA81, the aptX HD sounded so good; I actually found myself doing critical listening with it on.
Some people won’t be able to get past the lack of a screen and fine adjustments, but for me, I find it refreshing to plug in a great pair of speakers like the Kef LS50s or Q Acoustics 3020i and be able to enjoy my hi-fi without a whole lot of messing around. That’s what it’s all about. This amp will be going on our Recommended Gear page ASAP.