3e audio A7/A7 Mono Amplifier Review

[TurtlePaul]

Seeing the commentary on the B100 vs A7, I choose the A7 because with both having excellent audible performance at low signals, the A7 has 2-3 dB more power which increases to 5-6 dB extra power into complex loads. I am disappointed that Amir didn’t run the complex loads simulator on the B100 as this is one area where class D amps crush Class B/AB.

 

[Roland68]

Wouldn't this unrelated and OT post be considered an advertisement by an audio company?

@3eaudio is registered here as a manufacturer and posts a notice about their survey for planned multi-channel amplifiers with integrated power supplies in a review thread for one of their own amplifiers.
That's truly reprehensible .
Especially considering that there have already been countless user inquiries about this very topic in this and other threads.
I hope you understand my sarcasm.

Or don't we want to support a company that develops and manufactures well-measured and affordable products in developing exactly the products we want in the future?

 

[SnakeLord]

Seeing the commentary on the B100 vs A7, I choose the A7 because with both having excellent audible performance at low signals, the A7 has 2-3 dB more power which increases to 5-6 dB extra power into complex loads. I am disappointed that Amir didn’t run the complex loads simulator on the B100 as this is one area where class D amps crush Class B/AB.

A7 compared to the B100 (~230W vs ~90W @ 1% THD into 4 Ohm) is a big deal.
I see no reason why would anybody go for class AB over clean and powerfull class D nowdays.

@3eaudio
What has happened to your website? Got a new one?

 

[harkpabst]

A7 compared to the B100 (~230W vs ~90W @ 1% THD into 4 Ohm) is a big deal.
I see no reason why would anybody go for class AB over clean and powerfull class D nowdays.

The B100 is actually class C with super massive negative feedback.

 

[Chaos01]

Seeing the commentary on the B100 vs A7, I choose the A7 because with both having excellent audible performance at low signals, the A7 has 2-3 dB more power which increases to 5-6 dB extra power into complex loads. I am disappointed that Amir didn’t run the complex loads simulator on the B100 as this is one area where class D amps crush Class B/AB.

I think Amir did run the complex load to 2 Ohm with the B200, it did not Work at all degrees If i remember right.
Would Love to see a bit lower distortion from 5 to 15kHZ from the 3e A7, more Like the A5 that is a bit better with this. But for the price both are still nice, low distortion at high frequencys exist at Hypex ncx or purifi for 3 or 4 Times Higher Pricetag. But maybe in some years 3e Audio got this Level of distortion and Power Output too Till then i enjoy my A7.

 

[Roland68]

I think Amir did run the complex load to 2 Ohm with the B200, it did not Work at all degrees If i remember right.
Would Love to see a bit lower distortion from 5 to 15kHZ from the 3e A7, more Like the A5 that is a bit better with this. But for the price both are still nice, low distortion at high frequencys exist at Hypex ncx or purifi for 3 or 4 Times Higher Pricetag. But maybe in some years 3e Audio got this Level of distortion and Power Output too Till then i enjoy my A7.

The lower distortion of the A5 is due to the TPA3251 used, which is slightly lower than that of the 3255 in the A7. Overall, these amplifier ICs are pushed to their limits. As you can see, there have only been minor improvements since the introduction of the PA5 a few years ago.
Nevertheless, these are the devices with the best price-performance ratio in terms of price, performance, and measured values.

 

[TurtlePaul]

The B100 is actually class C with super massive negative feedback.

It is actually class B. Class C only really works in bandpass situations at high frequencies by resonating a tuned output filter. it pretty much doesn’t work at all at low frequencies.

 

[JW001]

It is actually class B. Class C only really works in bandpass situations at high frequencies by resonating a tuned output filter. it pretty much doesn’t work at all at low frequencies.

There isn't much sense to talk about class B. Any reasonable design includes some biasing of push-pull devices, whether they are tubes, BJT or MOSFET transistors, so it's always class AB. But let's not split hairs.

 

[xanalog]

Thank you, Yes not ELNA Silic II, but Rubycon YXF (105°C, Low ESR, high performance and long lifetime) are regarded as good caps. Where positioned/implemented, would you consider these Rubycon as not as good as ELNA or higher performing? Ignore the values, just pictures for comparison.

View attachment 483739 View attachment 483741

I think the violet color capacitors are the best to extract that last bit of smooth female articulation in any music!

 

[xanalog]

OT?:
2025/06/08 >> I purchased a 3E A7stereo (at the time, branded as Soyyin) from audiophonics.fr for $412.27USD**
2025/12/21 >> current aliexpress price for the same 3E A7stereo is at a total cost of $462.54USD*
2025/12/21 >> Current amazon price for the same 3E A7stereo is at a total cost of $330.77USD*
*Price includes taxes+S/H+**tarriff

Did I get ripped off: Perhaps!
Do I have buyer's remorse: Heck, No!

 

[anonyless]

OT?:
2025/06/08 >> I purchased a 3E A7stereo (at the time, branded as Soyyin) from audiophonics.fr for $412.27USD**
2025/12/21 >> current aliexpress price for the same 3E A7stereo is at a total cost of $462.54USD*
2025/12/21 >> Current amazon price for the same 3E A7stereo is at a total cost of $330.77USD*
*Price includes taxes+S/H+**tarriff

Did I get ripped off: Perhaps!
Do I have buyer's remorse: Heck, No!

i paid about 180$ including shipping for the A5 only a couple of months ago. it now sells for 275$ ..
AE is "buy on sale" only platform. if you're not using some coupon , you're doing it wrong (kind of)

 

[TurtlePaul]

OT?:
2025/06/08 >> I purchased a 3E A7stereo (at the time, branded as Soyyin) from audiophonics.fr for $412.27USD**
2025/12/21 >> current aliexpress price for the same 3E A7stereo is at a total cost of $462.54USD*
2025/12/21 >> Current amazon price for the same 3E A7stereo is at a total cost of $330.77USD*
*Price includes taxes+S/H+**tarriff

Did I get ripped off: Perhaps!
Do I have buyer's remorse: Heck, No!

They were $240 on Amazon for Cyber Monday.

 

[harkpabst]

It is actually class B. Class C only really works in bandpass situations at high frequencies by resonating a tuned output filter. it pretty much doesn’t work at all at low frequencies.

Sorry for the confusion, I had a senior moment. It's class B, of course.

There isn't much sense to talk about class B. Any reasonable design includes some biasing of push-pull devices, whether they are tubes, BJT or MOSFET transistors, so it's always class AB. But let's not split hairs.

This is exactly the design principle.of the B100/B200. No (or let's say ultra low) biasing and letting Ultra high feedback take care of the crossover distortion.

That's where their efficiency stems from.

 

[JW001]

This is exactly the design principle.of the B100/B200. No (or let's say ultra low) biasing and letting Ultra high feedback take care of the crossover distortion.

That's where their efficiency stems from.

That's the design principle? To achieve low distortions, care should be taken to reduce distortion at every stage of the amplifier. Not sure what kind of efficiency you are talking about.

 

[TurtlePaul]

That's the design principle? To achieve low distortions, care should be taken to reduce distortion at every stage of the amplifier. Not sure what kind of efficiency you are talking about.

Care does not need to be taken to reduce distortion at every stage of the amplifier. Negative feedback can reduce nearly any distortion within the loop. If you can make an amp with a little more distortion but a lot more gain, then you can use a lot more feedback and you will end up with less output distortion. Feedback can be hard to implement because it can also drive an amp into oscillation.

Linear amplifiers (Class A, Class B, Class AB) have not had to struggle with this as much as Class D amps, because linear amps have much more bandwidth. However, I suspect that Topping has taken some of the learning from the Class D space and now are using it to make linear typologies with much much higher feedback ratios than previous designs. If they have found a way to add 20 dB + more feedback to the loop, perhaps by increasing the order of the roll-off of the feedback filter, then perhaps they were able to make the amp operate in a regime that crossover distortion is not too relevant.

The efficiency is power efficiency. The bias current to push the output transistors outside their non-linear regions uses power. The output transistors being active even at zero output power uses power. A class B amp has theoretical maximum efficiency of 78.5%. A class A amp has a theoretical max efficiency of 25% at full power and power usage does not scale down with lower signals. A Class AB amp acts like class A below a certain threshold - power remains flat below this level.

 

[harkpabst]

That's the design principle? To achieve low distortions, care should be taken to reduce distortion at every stage of the amplifier. Not sure what kind of efficiency you are talking about.

Sorry, I'm just the messenger. Go, do your own research.

@TurtlePaul has already provided some good advice and answered some of your questions.

 

[TheHighContemplator]

Well, I've had the A7 Monos for a couple of weeks now, and they do everything I need. Black noise-floor, and no audible distortion at any volume my ears can handle. I also get good dynamics at lower output levels, they barely get warm, and my system has been a delight listening session after listening session. Thank you, @3eaudio . Great design, with incredible performance, at a very reasonable price. Can't ask for more than that.

 

[Deleted member 88178]

Is there any real advantage on using a pair of A7 mono instead of the A7 stereo if one is not using long XLR cables?
Apologies if this has been commented before
ps: both are available again @ audiophonics (they had been sold out for a while)

 

[Chaos01]

Is there any real advantage on using a pair of A7 mono instead of the A7 stereo if one is not using long XLR cables?
Apologies if this has been commented before
ps: both are available again @ audiophonics (they had been sold out for a while)

The monos give around ~480W at 2ohm per Channel at the Same time, while the stereo gives max. ~ 240w at 2ohm per Channel at the Same time. As Long as you use the 48V 10A Power supplys.
So dont know of youre speakers need that much at 2ohm and the content needs it at the Same time, depends.
8 and 4 Ohm W should be identical +-10W, right?
Maybe better Channel seperation but the A7 stereo got already very good seperation.
Less Gear with the Stereo
EDIT: maybe the monos have better Heat dissaparion? Not shure about that.
Happy Christmas

 

[Deleted member 88178]

The monos give around ~480W at 2ohm per Channel at the Same time, while the stereo gives max. ~ 240w at 2ohm per Channel at the Same time. As Long as you use the 48V 10A Power supplys.
So dont know of youre speakers need that much at 2ohm and the content needs it at the Same time, depends.
8 and 4 Ohm W should be identical +-10W, right?
Maybe better Channel seperation but the A7 stereo got already very good seperation.
Less Gear with the Stereo

Thanks!
And happy Christmas!