• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

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

@3eaudio could you please advise why amp is relatively loud at 9'o clock for balanced and unbalanced low gain selection.
Is there any channel imbalance in the 9 o'clock position of the volume knob? It shouldn't.
 
This seems to be an issue of overlap and hysteresis.
I did some acoustical measurements today and found the hysteresis (the difference between the switch-off voltage and switch-on voltage) to be absolutely minimal, <= 1 dB, which equals a difference of around 0,4 mV. I measured using pink noise, though. Signals with a different spectral distribution might lead to a slightly different behavior.

Maybe I'll find the time to share the measurements tomorrow.
 
Moreover, a power amplifier without a knob would look better.
So true
Folks, my A5 is switching off automagically when I listen at night. Wiim Ultra volume level is at 10, and this is already triggering the auto-off mechanism. :/

A bit disappointing, TBH.
Argh sad to hear. As I understand correctly, the amps also don't automatically power on when power is reconnected so adding 12v triggering to the power supply won't matter either?
Moreover, a power amplifier without a knob would look better.
Yes please.

It's great to read so many great listening impressions, but I think the auto sensing is probably going to bugger me. I'm definitely holding off for the next product with 12v triggering, internal PSU and without volume knob maybe ;)
 
@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.
@vbutani
from the info you shared, you DAC had 4.4Vrms and 2.2Vrms in RCA,that is huge high if this output is fixed, i beleive all amp will output very high as it has 16-23dB gain for a normal amplifier.
 
for the auto on/off, we are eveluating some change in both HW and FW in next build, to adjust the senstivity higher to support it not turn off faster.

currenttly for some people user case,we suggest below 2 simple way.
  1. adjust higher input cource volume a little bit,this may case by case as the music may diffenent
  2. use volume control on the A5/A7 side
 
for the auto on/off, we are eveluating some change in both HW and FW in next build, to adjust the senstivity higher to support it not turn off faster.

currenttly for some people user case,we suggest below 2 simple way.
  1. adjust higher input cource volume a little bit,this may case by case as the music may diffenent
  2. use volume control on the A5/A7 side

Why don't you type what you are trying to say in Chinese in ChatGPT first and ask it to translate it for you to English?
I can barely understand your English at times. Sorry.
 
for the auto on/off, we are eveluating some change in both HW and FW in next build, to adjust the senstivity higher to support it not turn off faster.

currenttly for some people user case,we suggest below 2 simple way.
  1. adjust higher input cource volume a little bit,this may case by case as the music may diffenent
  2. use volume control on the A5/A7 side
If you build the next A7 / or Mono Version with a normal 3,5mm headjack Trigger, i would buy it.
 
As I understand correctly, the amps also don't automatically power on when power is reconnected so adding 12v triggering to the power supply won't matter either?
No, they do power on automatically whenever the power has been disconnected and is then reconnected. The default state after connecting the PSU is on.

If the external PSU is connected all the time (and it's not switched off and on using a manually switched power strip or some triggered power switch) tgis is a different scenario. The A5/A7 will enter standby mode after 5 minutes of too low input signal and it will wake up from standb when a high enough input signal is supplied.

This is a form of two-point control, so the voltage thresholds for standby on and standby off must differ a bit to ensure stable operation. This has also been referred to as hysteresis here in the past. I see absolutely no benefit in vastly suffering threasholds. The least difference that will keep the device from switching on and off and on and off all the time is the best choice. This difference is very small already.
 
Same here.
Please add 12V trigger, ideally as an option with a 3 way switch (always On / Trigger / Auto Sense), same as for example with XTZ amps.

Thanks
Juergen
then you can put an option for the next version of integrated amp:facepalm:
 
then you can put an option for the next version of integrated amp:facepalm:
I understand your frustration, it may simply be a matter of reducing the sensitivity of the 'auto standby' so that it requires silence to switch off.

Sorry, I don't understand what you want to say.
Many power amplifiers (not integrated amps) have this option.
A trigger is the most reliable option, and many of potential sources have this option.

Over here: https://www.audiosciencereview.com/...finished-amplifier-with-pffb-is-coming.54799/

This is a thread where different potential models are discussed, and their are possible future options of an amp containing power supply. If I look at DACs it seems to be the slightly more expensive models that have the 12v trigger, so no doubt this is a cost saving measure relying on auto standby.

IMO a manual on/off would be the low cost compromise.
 
I understand your frustration, it may simply be a matter of reducing the sensitivity of the 'auto standby' so that it requires silence to switch off.



Over here: https://www.audiosciencereview.com/...finished-amplifier-with-pffb-is-coming.54799/

This is a thread where different potential models are discussed, and their are possible future options of an amp containing power supply. If I look at DACs it seems to be the slightly more expensive models that have the 12v trigger, so no doubt this is a cost saving measure relying on auto standby.

IMO a manual on/off would be the low cost compromise.
A Always ON and Auto Switch would be a slight better alternative.
But for me personally Not. With to Stereo Speaker and a Center Speaker in a 5.1 Setup, there is not much more annoying then On and Off switching Amp when there is No Input for the surrounds in silent szenes of a movie. Same with Front speakers when long dialogue parts are mostly played from the Center Speaker.
I dont know much Power amps with this Auto funktion without a 12v jack Trigger, so for me the Trigger is a must have :( and Always ON is not so good for longevity of parts
 
A Always ON and Auto Switch would be a slight better alternative.
But for me personally Not. With to Stereo Speaker and a Center Speaker in a 5.1 Setup, there is not much more annoying then On and Off switching Amp when there is No Input for the surrounds in silent szenes of a movie. Same with Front speakers when long dialogue parts are mostly played from the Center Speaker.
I dont know much Power amps with this Auto funktion without a 12v jack Trigger, so for me the Trigger is a must have :( and Always ON is not so good for longevity of parts
Or lower sensitivity for the 'auto-off'.

I've a center channel languishing un-used. It seems to me that these low cost / high performance amplifiers are changing the 5.1 scene, but the only pre-amp options contain yet more amplifiers, and big boxes! I think people are hooking these amplifiers up from the RCA outs?

The question partly is what purpose these amplifiers? 3e are working on a multi-channel power amp ... but that is more amplifiers (in one). I'd like a mono center channel pre - only with a digital pass through - but what I want does not exist (I doubt)! :)
 
Got my A7 today and replaced a wiim amp with the A7 and a WiiM ultra. So far so good and no issues at all with auto on/off both during music or some TV input.

When we were playing really softly later this evening we were still at 20 on the wiim ultra though, which was probably as low as we'll ever play.

Impressed with the heft of the device, really well made. A bit too early to talk about sound quality buy it definitely felt really nice and balanced.
 
Last edited:
So many technical comments in this thread about A5/A7 and so little shared impressions in regard to its sound.

Guys - do you ENJOY its sound? How does it compare to your previous amps? How about the width of the sound stage? Does it improve the perceived depth of the sound stage or does it sound flat? Separation of instruments? Naturalness of sounds? Does it involve you into music emotionally? Or does it sound boring and listless? Do you hear more details or less? Any changes to the bass, mids, highs compared to your previous amps?
 
So many technical comments in this thread about A5/A7 and so little shared impressions in regard to its sound.

Guys - do you ENJOY its sound? How does it compare to your previous amps? How about the width of the sound stage? Does it improve the perceived depth of the sound stage or does it sound flat? Separation of instruments? Naturalness of sounds? Does it involve you into music emotionally? Or does it sound boring and listless? Do you hear more details or less? Any changes to the bass, mids, highs compared to your previous amps?
Really?
‍face plant emoji failure.
 
Got my A7 today and replaced a wiim amp with the A7 and a WiiM ultra. So far so good and no issues at all with auto on/off both during music or some TV input.

When we were playing really softly later this evening we were still at 20 on the wiim ultra though, which was probably as low as we'll ever play.

Impressed with the heft of the device, really well made. A bit too early to talk about sound quality buy it definitely felt really nice and balanced.
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.
 
So many technical comments in this thread about A5/A7 and so little shared impressions in regard to its sound.

Guys - do you ENJOY its sound? How does it compare to your previous amps? How about the width of the sound stage? Does it improve the perceived depth of the sound stage or does it sound flat? Separation of instruments? Naturalness of sounds? Does it involve you into music emotionally? Or does it sound boring and listless? Do you hear more details or less? Any changes to the bass, mids, highs compared to your previous amps?
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.
 
for the auto on/off, we are eveluating some change in both HW and FW in next build, to adjust the senstivity higher to support it not turn off faster.

currenttly for some people user case,we suggest below 2 simple way.
  1. adjust higher input cource volume a little bit,this may case by case as the music may diffenent
  2. use volume control on the A5/A7 side
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.
 
Back
Top Bottom