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

@3eaudio I found the Auto on/off feature of the A5 amp better than my SVS S1000 Pro subwoofer. When I set volume very low, my subwoofer goes to stand by, but amp remains on. For Sub, I use high level input using speaker out.
 
Thanks for the impressions, thats interesting. I have a wiim ultra too with a fosi za3 in my second room/ Office. I defenitly listen also under 20, Sometimes Just at Volume Set on 1, sitting 2m away. With SF Venere1.5 (6ohm) or Sometimes kef ls50 (under 4 ohm), sensetivity i have to Google.
So @henel321 what is jour listenig distance and what sensetivity have your speakers?
Could you Test with Volume Bypass Set on the A7 in what Volume Level with the wiim ultra the Amp goes Auto Off? That would be a nice reference.

@ironmine i guess to observed that many people with high thd distortig ab amps will miss the thd in class d amps. So Here we have nearly Purifi levels, so the Amp (a7) will Show what ever your speakers can give.
The speakers and amp is "busy" by the family actually using it today.. But I will do some checks tomorrow when I can leave it runneing when working at home. My son thought it was a noticeable difference versus before though, much tighter, especially at "higher volumes" - poor neighbors earlier today in other words. :-D

Speakers are Polk R500, if I remember correctly rated at 87dB and 8 ohms. These are used in a medium/larger living room (by european standards, say 40-45 sqm), the closest listening position is about 3.5 m from the speakers, but usually more.
 
I wanted to follow up with details on the A7 (not the SE model) amplifier that I received. I've provided a picture of the power supply that 3E audio included with the A7 amplifier - 48V/5A GaN power supply compared next to the 48V/5A non-GaN power supply that was provided by Fosi audio with my v3 mono amplifiers. Also, while going through the box that the A7 amplifier arrived in, I was happy to see that they included an IC puller in the event I want do some op amp swapping in the future.
 

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Could you Test with Volume Bypass Set on the A7 in what Volume Level with the wiim ultra the Amp goes Auto Off? That would be a nice reference.
Doing some quick testing and interval halving while doing the dishes it shuts of between 6-7 on the Wiim Ultra, and that's playing very soft acoustic music to be a bit mean. (Acoustic Winter on Spotify was my test loop. )

At this level I did not really make out the lyrics clearly at my listening location. A realistic lowest level for me that I would use would likely be around 15 on the Wiim ultra. (This is with the Polk R500, A7 set to passthrough, low gain and RCA connections from the Ultra as it doesn't have XLR)

I likely will never have an issue with this. People with more sensitive speakers listening near field might have though.
 
Doing some quick testing and interval halving while doing the dishes it shuts of between 6-7 on the Wiim Ultra, and that's playing very soft acoustic music to be a bit mean. (Acoustic Winter on Spotify was my test loop. )

At this level I did not really make out the lyrics clearly at my listening location. A realistic lowest level for me that I would use would likely be around 15 on the Wiim ultra. (This is with the Polk R500, A7 set to passthrough, low gain and RCA connections from the Ultra as it doesn't have XLR)

I likely will never have an issue with this. People with more sensitive speakers listening near field might have though.
It would be good to have the set max. Output level of the Ultra as a reference. 2V is way louder than 1V or less. Only then the volume setting can be used as a reference.

Sidenote:
As I am also uncertain about the auto-Off of the A7, I pulled the trigger yesterday and ordered a different power amp with a real trigger (and heavy and full sized too :cool: ).
Will hopefully connect it tomorrow. https://www.hifipilot.de/IOTAVX-PA40_1
 
Not sure if I missed it, but didn't see during a search. Is the balanced input sensitivity 4v?
 
It would be good to have the set max. Output level of the Ultra as a reference. 2V is way louder than 1V or less. Only then the volume setting can be used as a reference.
That's just the start. Even with the max output voltage se to 2 V rms in two different setups you still cannot properly compare the Ultra's volume settings.

The source or more generally the signal being played also plays an important role. If the source itself has a low level (never coming close to 0 dBFS) you'll have to crank up the volume more. It's not the average level that counts, short dynamic peaks will keep the amp alive easily. Finally, differing spectral density of the signal will also lead to different results. One would have to agree on a common input signal.

I ran some tests in my non-WiiM system, temporarily using my Lyngdorf TDAI-1120 as a pre-amp for the A5. Using Spotify Connect to the TDAI-1120 I used this signal:
Song: Pink Noise
Album: White Noise Sounds Compilattion
Artist: Acerting Art

In this setup the A5 went into standby mode with the Lyngdorf volume control set to -43 dB. It would reliably wake up at -42 dB. So, the thresholds for standby on/off only differ by a very small margin.

How meaningful is that in practice? Well, not very much. The spectral density of pink noise might be somewhat similar to music but it's level is absolutely constant. This is a recording of the SPL and the equivalent continuous sound level (both A-weighted) in my MLP. These are true absolute levels captured with REW's SPL meter logger and a calibrated UMIK-2:
SPL pink noise volume -42 dB.png


My room has a rather lowish (I think) noisefloor (again, A-weighted measurement):
SPL LAeq living room 2 mins comments.png


In this environment the pink noise signal played at 40 dB is not very loud but having it running in the backgrond was clearly uncomfortable. As I said, reducing the volume by just 1 dB step on the TDAI-1120 would have the standby kicking in after 5 minutes.

With real music or spoken word program material I can set the volume control around 10 dB lower (around -52 dB) without the A5 ever going into standby.

So, the pink noise signal would make volume readings comparable (when using the same pre-amp), but it's not well suited to judging if the threshold is acceptable in someones setup. Listening distance and speaker sensitivity are not relevant to determin wich volume setting will the amp allow to go into standby, but they are most important for the perceived loudness at the auto-off threshold.

Edit:
In my other setup using a WiiM Ultra with max output voltage set to 2 V rms the A5 goes into standby mode with the volume set at ~11.
As said before, the actual value depends on the source (and on settings like Pre-Gain and volume limit on the Ultra), but at ~3 m listening distance and using average sensitivity speakers (around 85 dB/1 W/1 m) this corresponds to very low volume.
Not a problem with watching TV or active listening to music. But when it comes to background music when the relatives are around I might well miss a function to disable automatic standby.
 
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Probably no reports because it doesn't "sound". :)

If you hear a difference, most likely the previous amp was flawed. Having said that I absolutely do enjoy the fabulous music in two of my systems using the 3e Audio A5.

So, the previous class D amps (Fosi V3, etc.) had a sound because they were flawed, but A5/A7 is flawless and has no sound?
If this is so, does it mean that the owners of A5/A7 are going to keep it/use it forever?
 
I wanted to follow up with details on the A7 (not the SE model) amplifier that I received. I've provided a picture of the power supply that 3E audio included with the A7 amplifier - 48V/5A GaN power supply compared next to the 48V/5A non-GaN power supply that was provided by Fosi audio with my v3 mono amplifiers. Also, while going through the box that the A7 amplifier arrived in, I was happy to see that they included an IC puller in the event I want do some op amp swapping in the future.
OPAmp puller is nice addition!
 
So, the previous class D amps (Fosi V3, etc.) had a sound because they were flawed, but A5/A7 is flawless and has no sound?
If this is so, does it mean that the owners of A5/A7 are going to keep it/use it forever?
Yes, of course.

Or they might roll op-amps and replace caps to add some "character". ;)
 
Hi 3e Audio. It is clear you have been following the various discussion groups from people who have received early shipments of the new A7 and A5 amplifier series. It seems quite a few people are having some problems with the Auto Power On / Off feature as music levels can quite often fall below the threshold to keep the Amplifier running. I had the same problem with your previous integrated amplifier as it kept turning off and you published a downloadable file which removed the functionality.

Would it be possible to make a small change to the software on the MCU so that a long press of the volume control switch (say >20 seconds) would toggle this feature on and off. This would require no changes to the current hardware design and satisfy most of you current and potential customers. It is my intention to purchase an A7 model as soon as it is possible to leave it running permanently with only a manual On / Off function.

On future products I would be in favour of having a physical Power Switch (not part of the volume control) that provides On / Auto / Off functions and another switch to select between the inputs. Should any of these product include Bluetooth (I am NOT in favour of this as it dates the product too quickly) could you ensure that the Bluetooth input can be selected manually and not be the default input that overides any other input when there is a bluetooth signal present. This has caused me so many issues with competitors products that I now avoid any amplifier products with Bluetooth functionality included !!

Many thanks for your support. James.
@Bushellj
Thanks for your great suggestion and currently we are evaluating your idea in software change.
by now,we had test some change on both HW and FW to achieve the senstitivy down to 250uVrms with RCA and 500uVrms in XLR,this improvement can cover most of the user case.
 
@Bushellj
Thanks for your great suggestion and currently we are evaluating your idea in software change.
by now,we had test some change on both HW and FW to achieve the senstitivy down to 250uVrms with RCA and 500uVrms in XLR,this improvement can cover most of the user case.
At some point you mentioned a possibility of a hardware DIY fix. Any details on that?
 
At some point you mentioned a possibility of a hardware DIY fix. Any details on that?
Regarding that proposal, I already asked (without answer yet), whether the original connector for the Trigger signal is still on the PCB?
If you check photos of the inside (i.e. at audiophonics HP), there is still the external connector with 3(?) short wires going to a connector on the PCB.
If that connector is still there, it would be quite simple to DIY a cable to the outside of the case and add a 3,5mm female connector there.
Or drill a hole in the case and do it properly...

Juergen
 
Regarding that proposal, I already asked (without answer yet), whether the original connector for the Trigger signal is still on the PCB?
If you check photos of the inside (i.e. at audiophonics HP), there is still the external connector with 3(?) short wires going to a connector on the PCB.
If that connector is still there, it would be quite simple to DIY a cable to the outside of the case and add a 3,5mm female connector there.
Or drill a hole in the case and do it properly...

Juergen
Sorry we may miss some post sometimes, actually the components of trigger are not populated yet,so it is hard to do that,also making a hole on the back panel won't be so easy.
we do have a solution by remove 1 resistor to increase the sensitivity by 14dB,RCA down to 400uV and XLR down to 800uV,but this also need some skill of diy...:eek:
 
Sorry we may miss some post sometimes, actually the components of trigger are not populated yet,so it is hard to do that,also making a hole on the back panel won't be so easy.
we do have a solution by remove 1 resistor to increase the sensitivity by 14dB,RCA down to 400uV and XLR down to 800uV,but this also need some skill of diy...:eek:
Which resistor?
 
So many technical comments in this thread about A5/A7 and so little shared impressions in regard to its sound.
Many here simply avoid to use fancy words for subjective opinion.
It may be different for you than me..... we all have different setup, but since you specifically asked.....

Guys - do you ENJOY its sound?
TOTALLY, there isn't going back for me unless it breaks

How does it compare to your previous amps?
For me, it's probably better than any other similar amplifier I have. I got a pre-production unit, it has replaced my Topping PA7 and I am not changing it back unless I see any issues not being a production unit.

How about the width of the sound stage?
Amplifier has nothing to do with it, it's speaker and placement w.r.t. sitting spot.
I use it with Ascend Sierra-lx and its as good as it gets.

Does it improve the perceived depth of the sound stage or does it sound flat?
***same as sound stage.

Separation of instruments?
Clean and clear separation, really really good

Naturalness of sounds?
Don't know how to calculate Naturalness, but overall its balanced and nothing feels out of the place.

Does it involve you into music emotionally?
Absolutely, whatever music has in it

Or does it sound boring and listless?
Not at all

Do you hear more details or less?
For me, its smooth and detailed. Very much like PA7.....

Any changes to the bass, mids, highs compared to your previous amps?
Time to time I can't escape the feeling that the mid and lower base is now better than before, low volume listening wasn't this good with other amps for me in the same setup.

Please note that I have used the stock 48v 5a PSU with PA7 while 48v 10a PSU with 3e's A7 amplifier in my setup. Topping PA7 has aviation connector and so I can not use my existing 48v 10a psu with PA7.
 
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I want to use op-amp Burson V7 Vivid pro (dual) on A5. 3e Audio wrote me "you need to set voltage to.30V. PLEASE see manual"
Manual say: Op-amp supply voltage equal or lower 30V, a dedicated setting(J30) is MUST to set supply voltage to
30V, refer to below picture.

But I can't find J30 on the board through the window (only J6). I guess I must disassemble device.
1. How to disassemble it?
2. If somebody use Burson V7 Vivid pro?
 

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