Cambridge CXA81 MKII Amplifier Review

[audioje]

At this point, is it safe to say audio devices from some (or most) 'old' companies are not only plain expensive but also technologically inferior?

 

[amirm]

At this point, is it safe to say audio devices from some (or most) 'old' companies are not only plain expensive but also technologically inferior?

They have been stagnant for sure. They just fight for market share with marketing and distribution.

 

[amirm]

STILL, I'd like to see double-blind tests proving that this matters.

You can get a system that makes this point moot, i.e. provide provable transparency. Why spend energy to prove that this is good enough after paying extra for it?

 

[Bleib]

+1.6v issue is incomprehensible. This isn't some start-up company

 

[Billy Budapest]

Performance is good in some aspects and pretty mediocre in others. I would have expected a lot better for $1100.

 

[Rja4000]

Hi Amir
Thanks for this review.

Another classic brand tested, which is good.
Amp seems OK, but DAC is for sure disappointing.

 

[posvibes]

Good heatsinks. Otherwise, well, you COULD listen to music with it. Not as much output power as I'd like to see for the money. Good to see solid amp performance all the way down to 20 Hz, speaks of a good stiff power supply.

The DAC doesn't measure very well. STILL, I'd like to see double-blind tests proving that this matters. I'd like to see scientific proof that listeners can hear the difference between this DAC vs something from, say, Topping. We can MEASURE a difference, but does that measurement translate to an audible difference- or are we just counting how many audiophiles can dance on the head of a $400 RCA plug? I don't know the answer. I WANT to know!

I had, well still have and occasionally use the Cambridge 651A, and the reason I bought it (at a reduced price at the time) is because of the features it had including the DAC and the USB input. The internal DAC from memory was "reviewed" as OK. When I do use the amp I am not biting my nails, nor weeping for the audible performance of the DAC, I can't hear the poorer performance of the DAC compared to the Topping Dac's I use.

For the price, they could just include a Topping or Fosi DAC inside the amp itself and still make a profit and better performance

 

[LTig]

You can get a system that makes this point moot, i.e. provide provable transparency. Why spend energy to prove that this is good enough after paying extra for it?

It could be a budget oriented design decision. Why pay more for a SOTA DAC when its performance is swamped in the power amp? Finally what counts is what comes out of the speakers.

 

[delta76]

great that @amirm is including thermal test now, would be valuable addition, especially for power amps.
one could wish we can retroactively test past amps, but we know that'd not happen

 

[ocinn]

Dumb question - but why are transformer based/linear power supplies still a thing in modern consumer/prosumer integrated amps and AVRs?

I assume the average purchaser of a $1200 stereo integrated amp - would value size, weight, efficiency (thermals), and cost over the “audiophile” logic that SMPS = bad.

In regards to this product, disappointing DAC performance, meh amp performance.

However, releasing an amplifier >2020 (esp as we see the industry trend towards bookshelf+sub vs tower speakers) that has pre-outs/sub out, but without any sort of (even rudimentary) hi-pass filter for the mains is disappointing.

While DSP based xover and delay would be optimal, a’la SHD Power (even the Sabaj A30A has hi-pass for the speaker outputs), a basic high-pass offers huge advantages over full range outputs when used with subwoofers.

Just my 0.02.

 

[DanielT]

Thank you for your review Amir.

______

Another example of a highly regarded English brand under performing. Can't help but feeling duped over many years by the HiFi magazines, who were glowing in their admiration for these brands.

For the same money you can have a minidsp Flex or WiiM front end, combined with a hypex power amp assembled by one of several competent manufacturers.

It must now be clear to even the most ardent "subjective" that the only way you can be assured of getting transparent and high performing gear is by measuring it. No ifs or buts.

Your work is invaluable Amir, thank you.

Edit: typo

But amplifier guru Douglas Self has worked with Cambridge Audio. That in itself does not automatically lead to SOTA amplifiers, unless the company wants to create such. However, they must have had some thought in that they hired such a knowledgeable person as Douglas Self, or?
But okay companies can sometimes bring in top notch experts, consultants for all sorts of reasons.

I think Douglas Self's most famous book is: Audio Power Amplifier Design. It is now in a sixth edition.

The Audio Power Amplifier Design Handbook

The Douglas Self Site, audio amplifiers, The Audio Power Amplifier Design Handbook

www.douglas-self.com

He has worked with several major companies, including Cambridge Audio

Douglas Self - Wikipedia

en.wikipedia.org

 

[Timmy]

great that @amirm is including thermal test now, would be valuable addition, especially for power amps.

As we’re probably just at the beginning of drastic global warming, the phenomenon of fatally overheating audio devices may very well be of some relevance in the near future. Therefore it really makes some sense to address this matter by adding heat photos to all coming (amp) reviews.

 

[JeremyFife]

Thanks for the review, it's always good to see 'mainstream' devices on test.

Liking the thermal image as part of the test suite ... not really liking much else.
I assume that it would work fine (sound fine), and the amp section does look forgiving. Not enough.

 

[Haskil]

Dumb question - but why are transformer based/linear power supplies still a thing in modern consumer/prosumer integrated amps and AVRs?

I assume the average purchaser of a $1200 stereo integrated amp - would value size, weight, efficiency (thermals), and cost over the “audiophile” logic that SMPS = bad.

The reliability of a linear power supply is known to be excellent in the long term and the design/manufacturing quality/cost ratio is favorable for such a device with multiple power rails.

The reliability and quality+cost ratio of design/manufacture of a switching power supply for a device more complex than a simple power unit is perhaps not as good...

In short, maybe a good old linear power supply is cheaper and more reliable for this type of device?

 

[Haskil]

+1.6v issue is incomprehensible. This isn't some start-up company

Why is this 1.6 volt pre out output level a real problem?
If the output impedance is low and the power block it could be connected to has a sensitivity of 0.775 volts, or even 1.5 volts... it should work, right?
I really ask the question, because I often see audiophiles advocating the use of preamps delivering 10 volts and more... What is the use of such a gain in a preamp when the level of unbalanced sources is 2.1 volts these days? ?
I really ask the question

 

[Haskil]

I voted poor, because warned of several defects discussed with Amir during a previous test, Cambridge Audio did not correct them.

But in absolute terms, you will find much more expensive and less efficient. And I am fairly certain that connected to good quality and fairly sensitive speakers, it will give complete satisfaction to its user who will probably not hear any audible fault.

 

[restorer-john]

Dumb question - but why are transformer based/linear power supplies still a thing in modern consumer/prosumer integrated amps and AVRs?

Reliability, short term capability surpasses switching supplies to allow fantastic dynamic abilities. Able to operate in much wider temperature extremes. Virtually immune to power line issues that can easily kill an SMPS. Can be grossly overloaded and not raise a sweat.

I would also expect the toroidal would be much easier to recycle for steel and copper (cut it in half and separate the windings and core) down the track.

 

[Michael Fidler]

They would have done better to make it as a stand-alone power amp IMO. Voted 'not terrible' but would have voted 'great' if it were just a power amp.

 

[Sokel]

That was expected, thanks @amirm.
I'll eat my hat if any of the mainstream Class AB design cross the -100dB barrier. What Benchmark did is/was remarkable.

Hmm...

I count another 4 just by what Amir has measured and we know of a lot more out there.

As for the review,moderate performance overall,fortunately at a low (relative) price.
Heat seems to be of a concern these days as we saw even at class D amps,so the old advise "look at the specific device and not the class" still stands.

Thanks Amir!

 

[Waxx]

The strange thing is, they have good dacs, that are quiet old but still ok. Their (relative cheap) DacMagic 100 from 2012 does 10dB better on the sinad scale (99dB) and also scores a lot better on other factors. I have it and use it daily on my office system.

https://www.audiosciencereview.com/...measurements-of-cambridge-dacmagic-plus.6887/

It's strange that the dac they make 12 years later scores so bad, even if it's build in an integrated amp. Tech became better and cheaper since then, so it should be better.