3e Audio A5 Stereo Amplifier Review

[dark132]

The "catch" would be long term reliability electronically, and thermal performance. If the Fosi v3 mono (and various Topping devices) have taught us, outstanding performance does not always acquaint to long term usage.

The other catch would be warranty? I can't see it available for sale anywhere other than Ali's Express.

Why? I use two power supplies to connect two Fosi v3 monos and work 4-6 hours a day for more than half a year. I have never found any problems and the heat is within the normal range.

 

[Saponetto]

Audiophonics France already distributes their power modules, so maybe we will see their amp line somewhere in the future.

 

[phoenixdogfan]

Seems impeccable to me. Only limitation is that it's essentially a 60 wpc amp into 8 ohms. The A7 mono at $180 ($360 pr) is a 150 wpc solution for those who want more power. But flawless, and you can use the volume control if you have a DAC without one of its own.

Financially it's becoming easier and easier to put the money into the things that really count--speakers, dsp, and room treatment.

Thank you for the review of this important product, Amir.

 

[JSmith]

I think you misread the comment you replied to? He said that Hypex and Purifi amps are non fatiguing, and asked if this amp would be the same. Unless there's something I'm not getting?

Ah, you're correct... I misread in haste and thought the post said fatiguing, bad day.

@Pritaudio, my sincere apologies! Post edited.


JSmith

 

[frabor]

What about a 48, 10 amp supply for the A7? According to the manufacturer, TI, the TPA 3255 can produce 600W in PBTL ( Yes, at 10% distortion). . With proper cooling and beefier supply, the TPA 3255 in pbtl should be able to generate more clean power. Note that the TPA3251 has better sinad at reduced power over the Tpa3255.

 

[amirm]

What about a 48, 10 amp supply for the A7?

This review is for A5, not A7. I do have an A7 and it has come with a monster power supply. I will test that very soon.

 

[JSmith]

As is inclusion of 12 volt trigger

Actually I gather you have the pre-prod version there, as on the prod model the 12V trigger has been removed (unfortunately). It has auto on/off signal detection though and low power standby after 5 mins of no signal.

- *** 12v trigger: production units will not have 12v trigger.

* image for A7, but same as A5 regarding no 12V trigger


JSmith

 

[delta76]

I'm not sure if there's an additional import tax on items from China when shipping to the US, but in Europe, we definitely have to pay extra for anything exceeding 150 EUR.

It is rather the seller will "adjust" the price to remove VAT from the item. You then have to declare and pay VAT yourself (mostly through the courier)

 

[capslock]

Would have been nice to see power vs distortion test.
regds

I concur. Specifically, I'am interested in the 15 kHz THD+N vs. Power graph.

Just this weekend, I was trying to figure out from Archimago's measurement where the A5 stand relative to the PA5 II. I came to the conclusion that the A5 was maybe at tad better, but it was hard to tell without that graph.

 

[ICIETDIYEUR]

People hi !

Congratulations to 3eAudio for making an almost perfect amplifier

It's unfortunate that we didn't show the inside of the device in order to see the specificity of the PCB layout and its cooling...

... This looks 'strangely' like a layout that I had imagined about 2 years ago and that had been the subject of discussion

 

[AudioSceptic]

Oh, I had a hard time figuring out what the price was on Aliexpress. I am told I have the A5. Let's confirm when company chimes in.

Can the label on the front not be trusted?

 

[wineds]

@amirm did you test power on/off for glitches?

 

[olieb]

As always, great review, THANKS!
I was waiting for this and the results are even better than expected (by me).
Stability at low load impedance is impressive.
Seems to be a very competent implementation in all respects.

 

[AudioSceptic]

This is a review and detailed measurements of the 3e Audio A5 Stereo class D amplifier. It was sent to me by the company and costs US $229.99.

View attachment 419242
Despite its simplicity, the A5 has very well thought out features. Clipping indicators are provided for each channel. And selection of inputs is made through volume control push action. Hold it in for more than 2 seconds and it will shut off the unit. The volume control can be bypassed using a switch and that is how I tested it:
View attachment 419243
Also nice is selectable gain for RCA. As is inclusion of 12 volt trigger for automatic turn on based when you power on a source with the same output. For the sources that lack that, the A7 uses signal detection on the inputs to power itself on and off. Very nice.

In use, the unit was robust, barely getting warmer than ambient temperature. Pushing it into clipping was no big deal as it would automatically and quickly reset to working condition.

There are two square holes underneath to expose the op-amps and let you replace them (I highly suggest that you do not). There are large air slots all around to provide good circulation.

"PFFB" is implemented so the amplifier should be load independent.

If you are not familiar with my measurements, please watch my tutorial on what the tests are and what they mean:

3e-audio A5 Measurements
Let's start with our dashboard using XLR input with volume fixed:
View attachment 419246
Distortion spikes are below threshold of audibility so noise sets our SINAD, ranking the A5 as one of the best amplifiers tested regardless of price:
View attachment 419247


View attachment 419248

RCA performance is almost as good which is a nice bonus:
View attachment 419249
Here is high gain:
View attachment 419250

Low gain is sufficient for full power with typical DAC providing 2 volts:
View attachment 419251

XLR gain is fixed but fortunately it too provided max power below 4 volts that DACs produce:
View attachment 419252

Frequency response as expected, is essentially load independent, with nary a resonance above 20 kHz:
View attachment 419253
Crosstalk was exceptionally good:
View attachment 419254

Multitone shows very respectable performance:
View attachment 419255
Distortion rises at high frequencies though so our 19+20 kHz suffers some:
View attachment 419256

Fortunately you are never going to play music with this kind of spectrum so mostly academic.

The low noise and distortion shows up in our power sweeps:

EDIT: it should say 122 watts, not 92.
View attachment 419257
View attachment 419258

We almost achieve the specified power rating at 4 ohm and 1 kHz:
View attachment 419259

New in my amplifier tests, is power rating at 40 Hz which represents the reasonable low frequency for vast majority of users of audio systems:
View attachment 419260

So you give up about 14 watts so not bad at all.

My reactive load box locks up if I test a BTL amplifier on its right channel. So here are the results of that but for only left channel driven:
View attachment 419261
View attachment 419262

Nice to see it continue to "double down" as impedances halve and halve again, albeit with one channel.

Sorry, forgot to run my test of power vs frequency.

But here is the warm up test:
View attachment 419264

Conclusions
The A5 amplifier is very well thought out small amplifier with excellent feature set and performance to back it. I love features such as clipping indicator to tell you whether you are exhausting all of its power. Measurements show one of the most implementations of this architecture with no weak point other than perhaps, high frequencies. All of this for a reasonable price. I am good at finding faults but I am without words when it comes with the A5.

I am happy to recommend the 3e-audio A5 stereo amplifier.

------------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

The chips are TI, aren't they? Is there a "reference" amp made by TI to showcase them?

 

[Niconoclaste]

Great measurements ! Thanks a lot Amir !

Is it planned to measure the detailed power VS THD+N, especially at 15kHz ?
Should we expect as well some measurements with a 48v PSU ?

Indeed TPA3251 means 38v max. Thanks @daniboun

 

[daniboun]

Hi amigos,

I think you should always provide contrast when giving an opinion)
I would therefore tend to compare this amp to the Topping PA5 II which was finally tested in August 2023 and which offers similar (or even better) performance at €169....
The performance / price ratio is just OK here...

@amirm > what about the Power VS Distortion@4R/45KHZ test ???

As reminder :

 

[daniboun]

Is it planned to measure the power VS THD+N, especially at 15kHz ?
Should we expect as well some measurements with a 48v PSU ?

This a TPA3251 chipset... )) DC Supply Voltage (PVDD_x) is 12 to 38V max

 

[Niconoclaste]

This a TPA3251 chipset... )) DC Supply Voltage (PVDD_x) is 12 to 38V max

Correct, thank you !

 

[Rja4000]

Actually I gather you have the pre-prod version there, as on the prod model the 12V trigger has been removed (unfortunately). It has auto on/off signal detection though and low power standby after 5 mins of no signal.


View attachment 419295

* image for A7, but same as A5 regarding no 12V trigger


JSmith

That's really too bad !

 

[MusicLover2112]

Will this be powerful enough to drive the Revel Performa3 F208 or do I need to jump up to the A7 or A7 Mono pair?