3e audio A7/A7 Mono Amplifier Review

[Mort]

AliExpress costs much more than from Amazon's. Found one with the AIYIMA brand on Amazon that should work: https://www.amazon.ca/gp/product/B0D48JNKD2/ref=ox_sc_act_title_1?, but Amazon does not sell an A7 Mono that doesn't include the 5 A supply. Wonder why they just don't seem to want to include the 9/10 A supply with those amps, I guess its the shipping cost as the 10 A ones are obviously heavier and larger so might cost too much for them to ship.

2x A7 mono and 2x Aimaya 10a power supplies are $480 in the US. I think I'd spend $100 more for a hypex nc252. But that's just me.

 

[peng]

2x A7 mono and 2x Aimaya 10a power supplies are $480 in the US. I think I'd spend $100 more for a hypex nc252. But that's just me.

Sure, I probably would too, but I already have a NC502MP and a Purifi Eigentakt so I prefer to try another chip amp. To me the Fosi V3 chip amp sounds the same as the Hypex and Purifi amps so I trust the 3eA7 can only do better, and I also like that it has the trigger and a higher gain, 3 dB higher, so that will work better with my desktop DACs and the miniDSP HTx. The HTx's 2 V max feels a little gutless when paired with the Hypex or Purifi amp driving my BMR bookshelf speakers, though it is more psychological because with volume at above -10 it is still loud enough.

If the A7 works out well, then I may sell either my NC502MP or the Eigentakt on eBay to recover a few hundred dollars (CAD), would be great to list it on ASR but it seems too complicated to ship things to the US.

​

 

[JRowland]

Right, I am in the GTA area, so basically Toronto in terms of calculating shipping costs. Also, technically speaking if you already have the 10 A splitter, you should keep it because it has better current capability for real world use when two channels don't always peak at the same time to the same magnitude. That's assuming the 10 A splitter is an external one, as that would likely mean the PS is a single transformer/bridge rectifier so it actually has the 10 A rating instead of 2 X 5 A. All these, like lots of other things, likely mean nothing in terms of audibly better SQ. but it sounds good in theory.

East coast, shouldn’t be too bad. You about talked me out of it entirely with all the sensical commentary I was thinking and could use some garage shelf space so those 2 V3 monos would work good for me if you are gonna sell them. I need a way to power them and the one in my bedroom that would lose the 10a. For what I’m using all of these v3s for now the theoreticals are not even in the picture so the 10a, splitter, and filter are space takers to me. If a convoluted package deal is of any interest to you lay out an offer of how many dollarbucks you would need from me.

 

[TurtlePaul]

2x A7 mono and 2x Aimaya 10a power supplies are $480 in the US. I think I'd spend $100 more for a hypex nc252. But that's just me.

I feel like much of what the nc252 has going for it is reputation - which works for Hypex amps and against Chinese amps.

- If you look at the failure rates, Hypex ‘cost optimized’ much harder than 3e. I am sure Hypex has reverted to low ESR caps to stem the failure rate but it isn’t a good look. Look at the heatsinks on these newer TPA3255 designs.

- The nc252’s 96 dB 1 khz SINAD, -0.5 dB at 20 khz frequency response, and protection at 2 ohm loads were good five years ago but aren’t the best today.

- Hypex is a little better at high frequency where are ears aren’t as good and has less than 1 dB more power, meh, who cares?

edit: and to be clear, these criticisms are specific to nc252mp and not other Hypex amps like NCX500, Nilai, etc.

 

[peng]

East coast, shouldn’t be too bad. You about talked me out of it entirely with all the sensical commentary I was thinking and could use some garage shelf space so those 2 V3 monos would work good for me if you are gonna sell them. I need a way to power them and the one in my bedroom that would lose the 10a. For what I’m using all of these v3s for now the theoreticals are not even in the picture so the 10a, splitter, and filter are space takers to me. If a convoluted package deal is of any interest to you lay out an offer of how many dollarbucks you would need from me.

will do.

 

[Mort]

I feel like much of what the nc252 has going for it is reputation - which works for Hypex amps and against Chinese amps.

- If you look at the failure rates, Hypex ‘cost optimized’ much harder than 3e. I am sure Hypex has reverted to low ESR caps to stem the failure rate but it isn’t a good look. Look at the heatsinks on these newer TPA3255 designs.

- The nc252’s 96 dB 1 khz SINAD, -0.5 dB at 20 khz frequency response, and protection at 2 ohm loads were good five years ago but aren’t the best today.

- Hypex is a little better at high frequency where are ears aren’t as good and has less than 1 dB more power, meh, who cares?

That's super helpful and valid.

 

[xanalog]

If I really want to buy 2 52 V/9A or 48 V/10A I will just sell the 48 V 5A PS on eBay, I think it won't be hard to sell them as the 48 V 5 A units seems have enough demands.

Why not post it FS, in our "Audio Equipment For Sale or To Buy" thread, first?

 

[peng]

Why not post it FS, in our "Audio Equipment For Sale or To Buy" thread, first?

Will do, but it will not be right away as I have to try and see if those 5 A PS will do a good job first.

 

[harkpabst]

... so I trust the 3eA7 can only do better, and I also like that it has the trigger and a higher gain, 3 dB higher, so that will work better with my desktop DACs and the miniDSP HTx.

There's no trigger input on the 3E AUDIO A7 (or any other amp from the same series).

 

[peng]

There's no trigger input on the 3E AUDIO A7 (or any other amp from the same series).

Thanks for the correction, it would be nice but I don’t really need it. Wonder how I got the wrong info.

 

[harkpabst]

Thanks for the correction, it would be nice but I don’t really need it. Wonder how I got the wrong info.

That's probably pretty easy: The review samples did have it, but not the series production units.

 

[Good Vibes]

There's no trigger input on the 3E AUDIO A7 (or any other amp from the same series).

Although it does have an auto sensing power on/off feature which in my opinion, is better than a 3.5mm trigger switch.

 

[harkpabst]

Although it does have an auto sensing power on/off feature which in my opinion, is better than a 3.5mm trigger switch.

I think so, too. But reading through the complaints here in the forum, we seem to be in the minority.

 

[xanalog]

Although it does have an auto sensing power on/off feature which in my opinion, is better than a 3.5mm trigger switch.

Yes,

Auto audio sensing power on/off can be disabled and enabled by user, in standby mode

• Long push volume knob for 5seconds until RCA LED flashes for 3seconds and then off

 

[harkpabst]

Yes,

This is true from the second batch on, only.

 

[peng]

I dont really think thats what it is, I expected an improvement in this department after switching from the kefs. Other people have said this about class D

That could be part of the problems, internet hearsay (such as the different amp/dac/opamps, even cables have audibly different sound signature regardless tends to help reinforce expectations bias and Placebo effects. That doesn't mean there are in fact real reasons in your case, that you have not discovered yet. The fact is, based on specs, verified by measurements the A5/A7 amps will just amplify the input signal without distorting it to the point you seem to be getting.

 

[peng]

I bought a 3e A7Se to compare it with my vintage Sansui AU-D7. I’m curious to hear how a Class D amp performs in my setup. Honestly, when I ordered it on AliExpress, I didn’t even notice those last two letters


It’s already on the way, and I can’t wait to test it. I’m a little concerned about the 4 Ω – 16 Ω rating of the A7Se, though—hope it won’t be an issue.

Have you done any comparison listening yet, is the A7 Se driving your speakers well (I fully expect that and hope not to be wrong)?

 

[peng]

Thanks, if I do that, I still has to figure what to do with the two 48 V 5 A PS that will be included with the A7 Mono. I guess take a hit and sell them on eBay for cheap. I already have a couple of those for my Fosi V3 amps too. It just never make technical sense to me for them to include 5 A supplies with the A7 Mono, even worse for the A7 stereo. I just sent a PM to 3 e enquiring about the possibility to order directly from them (like Fosi does) but I am not hopefully that they would reply.

Got a response, was told the 48 V 5A is fine, no need for the 10 A one. I believe him as it makes total sense, given the choice I would still go with the 10 A but as I said before it is a "want" not "need". Given there is no choice I am happy with their answer and understand why there's no choice for me.

 

[TheHighContemplator]

Got a response, was told the 48 V 5A is fine, no need for the 10 A one. I believe him as it makes total sense, given the choice I would still go with the 10 A but as I said before it is a "want" not "need". Given there is no choice I am happy with their answer and understand why there's no choice for me.

Congrats. Looking forward to your thoughts. I'm in the GTA, as well. What speakers are you going to be powering with the A7 Monos?

 

[peng]

Congrats. Looking forward to your thoughts. I'm in the GTA, as well. What speakers are you going to be powering with the A7 Monos?

BMR bookshelf or KEF R900.