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3e Audio A5 Stereo Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 5 1.7%
  • 2. Not terrible (postman panther)

    Votes: 11 3.8%
  • 3. Fine (happy panther)

    Votes: 50 17.1%
  • 4. Great (golfing panther)

    Votes: 226 77.4%

  • Total voters
    292

amirm

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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.

3e audio TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier balanced review.jpg

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:
3e audio TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier balanced back panel review.jpg

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:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Measurement.png

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:
Best desktop TI class D amplifier review.png



Best desktop TI class D amplifier zoom review.png


RCA performance is almost as good which is a nice bonus:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier RCA Low Gain Volume Bypass Measurement.png

Here is high gain:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier RCA High Gain Volume Bypass Measurement.png


Low gain is sufficient for full power with typical DAC providing 2 volts:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier RCA Low Gain Volume Bypass SNR Measurement.png


XLR gain is fixed but fortunately it too provided max power below 4 volts that DACs produce:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass SNR Measurement.png


Frequency response as expected, is essentially load independent, with nary a resonance above 20 kHz:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass frequency response Measu...png

Crosstalk was exceptionally good:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass channel seperation Measu...png


Multitone shows very respectable performance:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Multitone Measurement.png

Distortion rises at high frequencies though so our 19+20 kHz suffers some:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass 19 20 kHz intermodulatio...png


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.
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Power 4 ohm Measurement.png

TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Power 8 Measurement.png


We almost achieve the specified power rating at 4 ohm and 1 kHz:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Max and Peak 1 kHz  Powe...png


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:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass 40 Hz ASR Power 4 ohm Me...png


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:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Reactive Speaker Load Te...png

TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass Reactive Speaker Load Te...png


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

Edit: other measurements:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass THD vs Frequency Measure...png

TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier XLR Volume Bypass power on off A5 3e audio...png


Here is the warm up test:
TPA3251 TPA3255 Based PFFB Class D Stereo Amplifier Warm up Measurement.png


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/
 
Last edited:
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 $179.99.

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:
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/
Thank you @amirm.
Pls add multitone if it was tested.

@3eaudio Congrats for excellent product.

P.E. Realized I missed that Amir already mentioned he forgot to test.
 
Perhaps I am reading the graph wrong....

'Max power' at 4 ohms is listed as 92 watts

Should Max power at 4 ohms read instead 122 watts ?
 
3e Audio A5 Stereo class D amplifier
Nice, excellent measurements and the casework is also appealing, with a cracking price to boot. Thanks for the testing.

The A5 uses the TPA3251.

They also have the A7 which uses the TPA3255, having more power than the A5.

3e Audio really should be a little more realistic about power output though on their product page, which are claimed to be higher than measured here, but not too bad.
'Max power' at 4 ohms is listed as 92 watts

Should Max power at 4 ohms read instead 122 watts ?
Seems you're correct, so power closer to published spec @122W instead of 92W@4R.


JSmith
 
Can't buy another class D with separate power bricks but it's another fine entry in the category.
 
wow
I really like the "bypass volume" switch in back. Seems like a great value

@amirm is this the A5 or the A5se? Their aliexpress storefront has the A5se as $179 and the A5 as $229. Product matrix below--I'm not really sure what effect the different implementations would have.

1736224357581.png


I will be considering an A7 to finally power my mains vs the avr
 
Perhaps I am reading the graph wrong....

'Max power' at 4 ohms is listed as 92 watts

Should Max power at 4 ohms read instead 122 watts ?
Yes, that is a typo. Put a note above it. thanks.
 
@amirm is this the A5 or the A5se? Their aliexpress storefront has the A5se as $179 and the A5 as $229. Product matrix below--I'm not really sure what effect the different implementations would have.
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.
 
I could point out specific amazing test results but they are all consistently good and that it would be pointless. Well done!
Agreed

I will instead point out the inclusion of thoughtful features:

12 volt trigger input
Gain switch for RCA input
Volume bypass switch
Clipping Indicators !
 
is there any evidence to suggest these will be as non fatiguing as the hypex or purifi class d designs.
Is there any evidence to suggest that Hypex or Purifi based amps are "fatiguing"? Question is moot...

edit: apologies, I thought you posted fatiguing rather than non-fatiguing when reading on a phone... maybe it was the missing hyphen that threw me. ;)


JSmith
 
Last edited:
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