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3e Audio A7 [TPA3255 PFFB Stereo] Finished Amplifier - User Impressions | Owner's Thread

How was the volume of the A5 set when it switched off?
You may try to reduce the volume on the A5 and compensate that with a higher volume on your source.
This way, you have a better chance that auto On/Off will not trigger ...

Hopefully ...

BTW:
I am still struggling whether to buy an A7 or not due to the missing trigger.
On the current pictures of this amp, there is no more trigger input. The pictures of the insides however still show the trigger input with 3(?) wires going to a connector on the board.
Would one of the owners be so kind and check whether this connector is still present on the board?
This way you could DIY your own wire connection with an external female 3,5mm jack connector .....
 
Yesterday, I was watching the Shogun series on Disney, and the volume on my Sony Bravia was set to 27%. It wasn’t exactly quiet—the sound filled the room quite well. However, during a moment of silence and contemplation in the show, my A5 triggered itself to switch off. This suggests the threshold levels are definitely slightly off.

I’m still in the process of evaluating this amp. Compared to my old Class D Marantz, there are both pros and cons. The new amp offers better channel separation, improved stereo imaging, and more dynamic mids. On the other hand, the Marantz sounds more melodic, has deeper bass, a more rounded, and detailed resolution too. Maybe I’m just accustomed to its sound after all these years—it’s been with me for about 15 years, after all. That said, the A5 is not fatiguing at all—its upper frequencies are clean, crisp, and very pleasant.

I’ve been thinking about parting ways with the Marantz, but it’s likely going to stay and find a place in the kids’ room. It’s such a great all-in-one device, with a CD transport, FM radio, DAC, DAB, and a very enjoyable sound signature. Plus, it only cost me $400, which is excellent value even compared to options like 3e Audio or Fosi.
There should be silence for 5 minutes ... you need to raise a ticket with 3eAudio [edited] on aliexpress.
 
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Yesterday, I was watching the Shogun series on Disney, and the volume on my Sony Bravia was set to 27%. It wasn’t exactly quiet—the sound filled the room quite well. However, during a moment of silence and contemplation in the show, my A5 triggered itself to switch off. This suggests the threshold levels are definitely slightly off.

I’m still in the process of evaluating this amp. Compared to my old Class D Marantz, there are both pros and cons. The new amp offers better channel separation, improved stereo imaging, and more dynamic mids. On the other hand, the Marantz sounds more melodic, has deeper bass, a more rounded, and detailed resolution too. Maybe I’m just accustomed to its sound after all these years—it’s been with me for about 15 years, after all. That said, the A5 is not fatiguing at all—its upper frequencies are clean, crisp, and very pleasant.

I’ve been thinking about parting ways with the Marantz, but it’s likely going to stay and find a place in the kids’ room. It’s such a great all-in-one device, with a CD transport, FM radio, DAC, DAB, and a very enjoyable sound signature. Plus, it only cost me $400, which is excellent value even compared to options like 3e Audio or Fosi.
I still have my old PM6006, sounds good as it did on day 1 when I bought it may be 5 yrs back or so. Smooth and melodic as you said, but it’s really base heavy But it doesn’t have details and resolution that A7 brings, and it needs to be played to a certain minimum level (to me) to hear some details.
For years, I personally couldn’t get out of Marantz products but I clearly see benefits in trying a decently measured amplifier over those old bulky ones.
 
How was the volume of the A5 set when it switched off?
You may try to reduce the volume on the A5 and compensate that with a higher volume on your source.
This way, you have a better chance that auto On/Off will not trigger ...

Hopefully ...

BTW:
I am still struggling whether to buy an A7 or not due to the missing trigger.
On the current pictures of this amp, there is no more trigger input. The pictures of the insides however still show the trigger input with 3(?) wires going to a connector on the board.
Would one of the owners be so kind and check whether this connector is still present on the board?
This way you could DIY your own wire connection with an external female 3,5mm jack connector .....

It's on the bypass mode. Going for A5 volume control is not exactly what I want but probably will have to try it out.

There should be silence for 5 minutes ... you need to raise a ticket with Fosi on aliexpress.

It seems likely.

I just tested it, and it works after 5 minutes. What might have happened is the following:
  • There was a short[edited] silence, the trigger activated, sound appeared, but the trigger wasn’t canceled. That could be the issue.
And it's not Fosi, it's 3e audio.
 
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It's on the bypass mode. Going for A5 volume control is not exactly what I want but probably will have to try it out.



It seems likely.

I just tested it, and it works after 5 minutes. What might have happened is the following:
  • There was a 5-minute silence, the trigger activated, sound appeared, but the trigger wasn’t canceled. That could be the issue.
And it's not Fosi, it's 3e audio.
Thank you - duly edited - problem with being on more than one forum ...

You had 5 minutes of silence watching Shogun, or a moment? I think it's important to establish if yours is an isolated case or not...

You don't have feedback from 3e Audio as far as I can tell from their after sales support. So you might be amplifying the issue (forgive the unintended pun).

A lot of people are chipping in to help here, but they don't seem to have the same issue. And you are making me (probably) unnecessarily worried because I won't get to try mine for a couple of weeks! :)
 
It's on the bypass mode. Going for A5 volume control is not exactly what I want but probably will have to try it out.
You could use it temporarily on occasion only and switch bypass on otherwise. Not ideal (and probably works best if you use a switched power strip, because 3e Audio recommend to only flip the bypass switch with no power applied), but you must decide if it's worth it. As I have pointed out several times, @Archimago has shown that THD+N is just slightly reduced with volume control enabled and RCA high gain compared to bypass and XLR in up to 10 W. Even at around 30 W (where deviation is most pronounced) THD+N is still -83 dB.

You had 5 minutes of silence watching Shogun, or a moment?
That would come as a surprise to me, too.

I just tested it, and it works after 5 minutes. What might have happened is the following:
  • There was a 5-minute silence, the trigger activated, sound appeared, but the trigger wasn’t canceled. That could be the issue.
I felt like auto-off was happening a bit early on my A5 when I switch off the pre-amp, but turns out I was wrong. 4 minutes and 59 seconds can feel a lot shorter if you don't pay attention. ;) So in my case I can definitely say that the device works exactly as advertised.

Whether this is enough to ease your worries, @SMen, only you can tell. :)
 
Wiim Pro (Coax) -> Musician Pegasus R2R DAC Balanced output(4.4vrms) -> A5 Amp -> Dali Zensor 3 bookshelf 6ohm 88db sensitivity.

My DAC unbalanced output is 2.2vrms.
This should be no problem in theory.

When using Fosi V3 Stereo I generally set volume 11'o clock on the same setup.
I noticed that I need to set the volume very low, around the 7 o'clock position. Is this due to the A5's high power output or the volume potentiometer design?
The V3 Mono has 20 dB of gain (XLR) whereas the 3e Audio A5 just has 17 dB (see the manual). So you would normally expect the position of the volume control to be higher with the A5 than with the V3 Mono. If this is not the case (I didn't compare nor measure my amps yet) this would indicate a different characteristic of the volume pot, indeed.

@3eaudio might be able to step in and clarify.
 
That would come as a surprise to me, too.


I felt like auto-off was happening a bit early on my A5 when I switch off the pre-amp, but turns out I was wrong. 4 minutes and 59 seconds can feel a lot shorter if you don't pay attention. ;) So in my case I can definitely say that the device works exactly as advertised.

Whether this is enough to ease your worries, @SMen, only you can tell. :)
This seems to be an issue of overlap and hysteresis.

Prerequisites:
  • A) Signal with a value of 2 activates the auto-off feature.
  • B) Signal with a value of 5 activates the auto-on feature.

Test Scenario A:​

You turn on the amplifier with a signal level of 6. The volume is too loud, so you lower it to signal level 4.
  • 01:05: There is a moment of silence (signal level 1), triggering the auto-off.
  • 01:15: The volume increases again (signal level 4). The auto-on is not activated (or is, depending on interpretation the auto-off trigger is not canceled) because, as per prerequisite B, a signal level of 5 or higher is required to activate auto-on.

Test Scenario B:​

You turn on the amplifier with a signal level of 6.
  • 01:05: There is a moment of silence (signal level 1), triggering the auto-off.
  • 01:15: The volume increases again (signal level 6). The auto-on is activated (or not, depending on interpretation the auto-off trigger is canceled) because the signal level meets the condition in prerequisite B.
That's why systems with auto-sensing aren't ideal for home cinema or primary living room setups.
 
By "primary living room setup," I meant something you use for both music and TV, as I do.

If you're just listening to music, you're totally fine.
 
By "primary living room setup," I meant something you use for both music and TV, as I do.

If you're just listening to music, you're totally fine.
Frustratingly I am not yet able to try my A5.

Using Fosi V3 monos I've had my tv sound coming through my speakers for 30 plus minutes at less than 47db, measured just now with a hand held db meter 30 cm from the speakers.

If people's units here are cutting out with a gentle murmur coming through their speakers, then that would be a general problem to be fixed.

If not, then your unit may well have a specific issue, and surely needs to go back to 3e? Or you need to ask them for certain tests to perform.

POST EDIT - over here: https://www.audiosciencereview.com/...a5-stereo-amplifier-review.59870/post-2197873 someone else is reporting same issue. Progress.
 
Mind you, that is with a KF92 active class D Subwoofer which also has auto-off. If the Kef is going off automatically I am not sure you can blame the A5!
The A5 does not have a sub out ...

Post edit : this is getting slightly out of hand and needs to be tied down before the product gets (possibly incorrectly) maligned.
 
Frustratingly I am not yet able to try my A5.

Using Fosi V3 monos I've had my tv sound coming through my speakers for 30 plus minutes at less than 47db, measured just now with a hand held db meter 30 cm from the speakers.

If people's units here are cutting out with a gentle murmur coming through their speakers, then that would be a general problem to be fixed.

If not, then your unit may well have a specific issue, and surely needs to go back to 3e? Or you need to ask them for certain tests to perform.

POST EDIT - over here: https://www.audiosciencereview.com/...a5-stereo-amplifier-review.59870/post-2197873 someone else is reporting same issue. Progress.
No, i dont have a 3e audio Amp. You misunderstood. I would Not buy it because what is posted here.
 
No, i dont have a 3e audio Amp. You misunderstood. I would Not buy it because what is posted here.
Even more relevant ... that is exactly why @Piotr needs to establish with @3eaudio whether this is an isolated case, and why those here (I'm presuming more than a couple) with A5's or A7's or A7monos could play quiet music < 45 db or so and verify...
 
In my opinion, this isn’t specifically an issue with the A5 itself, but rather a general challenge with auto-sensing, as discussed in this post: AudioScienceReview Forum.

It seems particularly relevant to the very sensitive speakers I own. I suppose I’ll need to either get a new pair of bookshelf speakers or an amp with a trigger.
 
I got my A5se today.
I am not going to describe the sound, just some observations.
It is working ;-)
The volume pot is a bit flimsy, the knob has some slack and it wobbles. So I am happy to use the bypass.
It came with 5532s as expected. There is no goo around these.
A5se_a.jpg
A5se_b.jpg


The amp "sings" a bit. With high level (-10dB on a D10s) input of sine 1kHz-6kHz, one can hear the tone when no loudspeaker is connected. With an input of 2,5kHz and 0,2Vr in a normal quiet room I could still hear it 1m away from the amp. My Umik pics it up, too.
There is a discussion in the other 3eAudio 3255 board thread about this, too.
The auto sensing works for me, but I can imagine that people with high sensitivity speakers playing very softly in the background might experience the amp switching off.
With my Kef R3 there _no_ hiss for me, not even very close to the tweeter.

All in all I am totally pleased.

EDIT: I checked the auto-sensing function and found that with high gain single ended input and a sine of 200 Hz (assuming this to be in the range of maximal energy for typical music) the amp switches on at a threshold of 2.1mV_rms.
Switching off without signal took 300sec.
And with 1.9mV switching off took the same amount of time.
It looks like the function is frequency dependent.
With 100Hz I get a threshold about 5dB higher.
WIth 400Hz it is ≈1.3dB lower.
 
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Question to 3E Audio!

Hello! I received my mono amplifiers, everything is fine in principle, but I am absolutely not satisfied with the automatic switching on and off function. The amplifiers switch off when I listen to music at a low level of about 03 volume. In general, I would like the amplifiers not to switch off themselves. Is it possible to switch off this automatic function???
 
Question to 3E Audio!

Hello! I received my mono amplifiers, everything is fine in principle, but I am absolutely not satisfied with the automatic switching on and off function. The amplifiers switch off when I listen to music at a low level of about 03 volume. In general, I would like the amplifiers not to switch off themselves. Is it possible to switch off this automatic function???
So this might be a general problem with @3eaudio 's A* configurations then ...

I'm not sure '03' volume let's us know the threshold though... Probably there is a way to use a voltmeter (someone?) ... I've a Topping DAC that is deciding to switch itself off under short periods of silence for some reason - very irritating.
 
My chain:
Wiim Pro (Coax) -> Musician Pegasus R2R DAC Balanced output(4.4vrms) -> A5 Amp -> Dali Zensor 3 bookshelf 6ohm 88db sensitivity.

My DAC unbalanced output is 2.2vrms.
I also checked with unbalanced RCA option with Low and High gain both, It's already set at Low gain, but I didn't perceive any change while toggling between gain.

When using Fosi V3 Stereo I generally set volume 11'o clock on the same setup.

My DAC doesn't have volume control.
I set Wiim Pro digital volume to 100 for not losing quality by reducing it.
@3eaudio could you please advise why amp is relatively loud at 9'o clock for balanced and unbalanced low gain selection.

My DAC output impedance 1250 ohm.
A5 XLR input impedance 20k

I literally have to set digital volume on Wiim Pro to around 25 to keep A5 volume around 12'o clock for avoiding channel imbalance issue, but digital volume of Wiim introduces loss/distortion in my case. Please help, thanks.
 
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