3e audio A7/A7 Mono Amplifier Review

[Old_School_Brad]

The discussion about that track in particular -along with some other interesting points -starts in another thread and continues across a few more, beginning around this comment from Doodski:

WiiM Amp Pro Streaming Stereo Amplifier Review

I'm not sure why so many people on this forum are so focused on power. I have a 35m² open living space, a 50W amplifier, and just two speakers. I usually listen at around 12% volume, and it's already loud. If you have a family or a partner, when would you even need to go up to 60%? When no one's...

www.audiosciencereview.com

 

[NDA357]

Добрый день. Услышу ли я разницу, если поменяю A7 стерео на 2 A7 моно?

 

[Crook]

...but having got the great 3e diy modules and the 3e A5 stereo power amp with nice bypassable volume control, the perfection will be only achieved if @3eaudio make the auto-power-off deactivatable just the same as needed volume bypass for using our high end preamp, we need deactivatable auto-off feature BECAUSE WE LOVE TO LISTEN MUSIC OR MOVIES AT LATE NIGHT AND AT THAT SO LOW LEVEL, AUTO-OFF THINKS THERE IS NO AUDIO SOURCE AND IT DISCONNECT, AND ITS SO DISAPPOINTING but otherwise the 5A 3e Audio audiophile power amp is almost perfect and thank you again for it.

Auto on/off can be turned off on latest A7 and I assume A5 too. I have it turned off. Fine, but not much use for folks who bought the previous version. Vendor should test first and release fully finished amp, not use early adopters as beta testers.

 

[Sokel]

I should also remind that, for their ability to save on power supply (capacitor and transformer) size by using a high switching frequency, class-D amplifiers tend to have less temporary power storage (the abovementioned capacitor and transformer), which is kind of the design goal. I know I'm conflating amp with PSU, but kind of relevant

That depends on the PSU, high power Hypex PSUs or icepower integrated ones have more than 20000uF capacitance on board.
That's no small.

 

[Roland68]

Auto on/off can be turned off on latest A7 and I assume A5 too. I have it turned off. Fine, but not much use for folks who bought the previous version. Vendor should test first and release fully finished amp, not use early adopters as beta testers.

That's exactly what most users don't understand.
Devices that are fully developed and, above all, thoroughly tested are much more expensive. This is one of the biggest costs in development, because it takes months, not weeks.

Would you be willing to pay double or triple for the device?

Even many large, long-established manufacturers are now cutting costs in this area.

Honorable exceptions are manufacturers such as RME or Violectric/Lake People. And the prices aren't so high because they're greedy.

 

[antcollinet]

I should also remind that, for their ability to save on power supply (capacitor and transformer) size by using a high switching frequency, class-D amplifiers tend to have less temporary power storage

A switch mode PSU doesn't need anywhere near as much.

In a linear PSU, the low voltage capacitor is charged only during the peak of the mains 50 or 60 times a second. The bulk capacitance needs to supply all the current needed by the amp for up to 20ms.

With a switch mode supply the low voltage capacitors are effectively kept charged continuously at the switching speed of the PSU (typically at 10's or even 100's of kHz)

 

[SMen]

...but having got the great 3e diy modules and the 3e A5 stereo power amp with nice bypassable volume control, the perfection will be only achieved if @3eaudio make the auto-power-off deactivatable just the same as needed volume bypass for using our high end preamp, we need deactivatable auto-off feature BECAUSE WE LOVE TO LISTEN MUSIC OR MOVIES AT LATE NIGHT AND AT THAT SO LOW LEVEL, AUTO-OFF THINKS THERE IS NO AUDIO SOURCE AND IT DISCONNECT, AND ITS SO DISAPPOINTING but otherwise the 5A 3e Audio audiophile power amp is almost perfect and thank you again for it.

This won't apply unfortunately as you have a previous model, but the current model has sufficient sensitivity not to power off I understand. A fix at low level (because it should not matter at low level) is to activate the volume control and attenuate the amplifier a bit here too. For critical listening with your pre-amp at 'normal' volumes go back to volume bypass or just turn the dial to max volume ... no measured difference according to this review. Not ideal I agree, but might ease the frustration.

 

[andrew]

Two questions
1. I use a smart power board to turn on and off devices (rather than 12V triggers). Does the A7 Mono remember its state when the power is turned off such that when the power is turned on the unit is on by default?
2. What is the residual noise of the amp? (I’m looking to use it to driver compression driver and midrange in active, 100dB, horn speaker.)

 

[SMen]

Two questions
1. I use a smart power board to turn on and off devices (rather than 12V triggers). Does the A7 Mono remember its state when the power is turned off such that when the power is turned on the unit is on by default?
2. What is the residual noise of the amp? (I’m looking to use it to driver compression driver and midrange in active, 100dB, horn speaker.)

Answer to the first is simply that when the smart power goes on, the A7 Mono will then switch on, but it will be off by default having switched itself off.

 

[andrew]

Answer to the first is simply that when the smart power goes on, the A7 Mono will then switch on, but it will be off by default having switched itself off.

So, to be clear, it’s not possible to turn the amp on and off from a smart power board (or, in effect, the wall switch)?

 

[anonyless]

Two questions
1. I use a smart power board to turn on and off devices (rather than 12V triggers). Does the A7 Mono remember its state when the power is turned off such that when the power is turned on the unit is on by default?
2. What is the residual noise of the amp? (I’m looking to use it to driver compression driver and midrange in active, 100dB, horn speaker.)

just tested this on A5 (should be the same as A7 Mono) - manually put the amp in standby (leds off) . unplugged its power cord and waited about a minute. plugged power cord back in, it turned itself on (red RCA led on)

 

[SMen]

So, to be clear, it’s not possible to turn the amp on and off from a smart power board (or, in effect, the wall switch)?

With the unit in standby mode, when the smart power board goes off, the A7/A5 will switch off. When the power board goes on, then after a few seconds the A7/A5 will switch on. Mine at least responds to both music starting to be played from the source, and power going on.

 

[Ivy Mike]

Realistically, have I missed the window for ordering one of these, without risking the mega tariff? Wondering how fast delivery is, typically to the US, from those that received theirs off Ali.

 

[anonyless]

^^ to my understanding, 3e are working on opening an Amazon store. don't think you missed anything.
it took mine 11 days to arrive to a pick up point in Israel, which is pretty fast, but it wasn't stopped at customs (for some reason)

 

[Guddu]

Two questions
1. I use a smart power board to turn on and off devices (rather than 12V triggers). Does the A7 Mono remember its state when the power is turned off such that when the power is turned on the unit is on by default?

Auto sense should turn it ON after you power ON the smart plug.

 

[Robinson808]

Realistically, have I missed the window for ordering one of these, without risking the mega tariff? Wondering how fast delivery is, typically to the US, from those that received theirs off Ali.

I ordered mine on the 9th & it was delivered yesterday the 19th, 2 days late due weather delays. It cleared customs in 4 days.

 

[Ivy Mike]

I ordered mine on the 9th & it was delivered yesterday the 19th, 2 days late due weather delays. It cleared customs in 4 days.

Thanks. A little close for me though at this point if it gets delayed a week the penalty is severe. I am having some regrets on this one.

 

[Crook]

Thanks. A little close for me though at this point if it gets delayed a week the penalty is severe. I am having some regrets on this one.

Or it's a forced opportunity. If tariff is indeed 125%, you're looking at around $765 delivered. Buckeye are selling a Hypex NC252MP for €595, free US delivery. Presumably no tariffs. I know which I'd be buying in the US.

 

[jlx]

Or it's a forced opportunity. If tariff is indeed 125%, you're looking at around $765 delivered. Buckeye are selling a Hypex NC252MP for €595, free US delivery. Presumably no tariffs. I know which I'd be buying in the US.

Buckeye has already stated that his latest shipment of amp modules from Europe has incurred a 10% tariff so I would expect that a price bump is imminent

 

[Chaos01]

Nice to see this one finally reviewed. The 3e A5 did a little better, any ideas why? Possible because of the 38v instead 48v Powersupply?
Does the AliExpress come with 38v and the audiophonics with 48v, did i See right?

I looked Back to the Fosi V3 Mono, Kind of similar but much cheaper, not that much to justify the Higher price for the A7 for me maybe.
So that brings me to the questions to keep this little D amps apart.

How hot does the A7 get? And is the On Off Pop similar to the A5? This questions should be answered in cheaper class d Reviews to Pick out the ones which have longlivety. @amirm did a Heat Test at some amps i think?

So its Close to the v3 but much more expensive, but cheaper than a topping PA7 plus and similar Hypex amps. At least the 3e have nice heatsinks. Want to know If the Higher price is worth it..