3e audio A7/A7 Mono Amplifier Review

[GrahamHill963]

So I just received my amplifier today. I immediately noticed that the volume knob has about 2 mm of free play in it. Is this normal? It feels a little disappointing. I expected a knob without any freeplay .

The feel of the rotation of the knob itself feels solid and not too light.

Here some footage:

Video Unavailable

This video is unavailable.

streamable.com

Does anyone have this as well or should I return this to the seller?

 

[harkpabst]

So I just received my amplifier today. I immediately noticed that the volume knob has about 2 mm of free play in it. Is this normal? It feels a little disappointing. I expected a knob without any freeplay .

The feel of the rotation of the knob itself feels solid and not too light.

Here some footage:

Video Unavailable

This video is unavailable.

streamable.com

Does anyone have this as well or should I return this to the seller?

Yes, this is normal. Have fun with your excellent power amp.

 

[ziggurcat]

So I just received my amplifier today. I immediately noticed that the volume knob has about 2 mm of free play in it. Is this normal? It feels a little disappointing. I expected a knob without any freeplay .

The feel of the rotation of the knob itself feels solid and not too light.

Here some footage:

Video Unavailable

This video is unavailable.

streamable.com

Does anyone have this as well or should I return this to the seller?

It's the same with my PA5 II amp and L50 HPA. As @harkpabst mentioned, it is probably normal.

 

[GrahamHill963]

Thanks both. Much appreciated. Alas, though I won't use this knob that often.

The sound is excellent. A noticeable improvement over the SMSL DA-9 on DBR62's. Though completely subjective, bass much is tighter in my far from optimized listening room.

 

[xanalog]

...Does anyone have this as well or should I return this to the seller?

Stop playing with your knob; it probably causes internal anxiety, resulting in added noise/distortion.

 

[xanalog]

These are very old connectors from the aviation industry. Back then, there was an urgent need for connectors that could be secured and wouldn't easily come loose due to vibration.
Bakelit and Bakelite are brand names for the plastics used at the time, just like in lamp sockets or power plugs and sockets.

Perhaps true for the private (aviation) industry, but neither the military nor the commercial aviation (or aerospace) sectors has made use of these connectors... going back for at least 50years. [afaik]

 

[ziggurcat]

My A7 was delivered this morning! I am totally going to have the jimmy legs at work today...

There were some freak out moments this morning, though -- I checked the tracking on my phone on the way to work, and it said it was in New Brunswick (which -- for those who aren't Canadian -- is on the complete opposite end of the country from me), but the tracking from the website when I looked online as soon as I got to work said it was in my city. Also, the tracking information on my phone said June 5th. So bizarre, but there are photos proving it was delivered to the correct address. Not sure what glitch happened there...

 

[xanalog]

My A7 was delivered this morning! I am totally going to have the jimmy legs at work today...
...

[OT deleted]
Before you even hook-up your unit (when/if), please correct/interchange/erase the wrong L/R markings on the rear RCAs,

...so that there is no forgetting it, in the future... for you, your kin and/or the next owner (if any).
This is more like a note-to-self; as I aim to do the same, if/when mine arrives.

 

[ziggurcat]

/\ I don't see the red part of your reply ... in your reply... but when I clicked to reply to your reply [?] the red part showed up as above.../\
Before you even hook-up your unit (when/if), please correct/interchange/erase the wrong L/R markings on the rear RCAs,
View attachment 457034
...so that there is no forgetting it, in the future... for you, your kin and/or the next owner (if any).
This is more like a note-to-self; as I aim to do the same, if/when mine arrives.

That was something with the pre-production model. There are photos with the correct RCA labeling:

\

Edit: Not my photo, it's one from the seller feedback on the AliExpress page (dated in March 2025).

 

[ziggurcat]

I got my A7 set up, now. A word of advice for @3eaudio -- Can you please make it so that the volume bypass switch isn't enabled by default? I am pretty sure I was very close to blowing my speakers when I played a song for the first time. Because my DAC is in DAC mode, it outputs at max volume (I control volume from my amps rather than my DAC), and with the bypass enabled on the A7, it meant that it was double max volume!!

The other problem is that after I paused any sound, there are two audible pops that I can hear coming from my speakers (even at two feet away). This does not occur with my Topping PA5 II amplifier even when my ear is an inch away from the drivers (I even reconnected the PA5 II, and tested it out in the unlikely event that I hadn't noticed before). The pop is heard from both the tweeter and woofer. I have not tested to see if it has to do with the amp's auto sensing, but that is something I will have to do another time.

As it stands right now, I think I have to return the amplifier because that popping from pausing any sound is a non-starter for me.

Edit:

BTW, I am still going to give this thing a fair shake, though. I am going to see if the behaviour changes with auto sensing disabled. Failing that, I will try using a different DAC as the popping is virtually identical to a popping issue I have noticed with my D50 III's PEQ enabled (Important to note: I did not have PEQ enabled when the pops presumably from the A7 were observed). I have a Topping E50 DAC that I can use to rule out the D50 III as the culprit.

In my setup, I also have a Topping L50 HPA, which has a bypass feature, so I can daisy chain everything together. All three devices (DAC, HPA and amp) are connected to each other via balanced TRS cables. This is all to say that as an added test component, I will also try to connect the E50 directly to the amplifier to rule the L50 out as well. If that also fails to eliminate the popping, then I will have to sadly return the A7.

Settings on the A7 itself, after nearly blowing up my speakers (and surely freaking out my condo neighbours ), I only flipped the switch to disable the volume bypass. RCA Gain is set to Low (but I don't think it's applicable since I'm not using the RCA inputs?).

 

[Roland68]

I got my A7 set up, now. A word of advice for @3eaudio -- Can you please make it so that the volume bypass switch isn't enabled by default? I am pretty sure I was very close to blowing my speakers when I played a song for the first time. Because my DAC is in DAC mode, it outputs at max volume (I control volume from my amps rather than my DAC), and with the bypass enabled on the A7, it meant that it was double max volume!!

The other problem is that after I paused any sound, there are two audible pops that I can hear coming from my speakers (even at two feet away). This does not occur with my Topping PA5 II amplifier even when my ear is an inch away from the drivers (I even reconnected the PA5 II, and tested it out in the unlikely event that I hadn't noticed before). The pop is heard from both the tweeter and woofer. I have not tested to see if it has to do with the amp's auto sensing, but that is something I will have to do another time.

As it stands right now, I think I have to return the amplifier because that popping from pausing any sound is a non-starter for me.

Edit:

BTW, I am still going to give this thing a fair shake, though. I am going to see if the behaviour changes with auto sensing disabled. Failing that, I will try using a different DAC as the popping is virtually identical to a popping issue I have noticed with my D50 III's PEQ enabled (Important to note: I did not have PEQ enabled when the pops presumably from the A7 were observed). I have a Topping E50 DAC that I can use to rule out the D50 III as the culprit.

In my setup, I also have a Topping L50 HPA, which has a bypass feature, so I can daisy chain everything together. All three devices (DAC, HPA and amp) are connected to each other via balanced TRS cables. This is all to say that as an added test component, I will also try to connect the E50 directly to the amplifier to rule the L50 out as well. If that also fails to eliminate the popping, then I will have to sadly return the A7.

Settings on the A7 itself, after nearly blowing up my speakers (and surely freaking out my condo neighbours ), I only flipped the switch to disable the volume bypass. RCA Gain is set to Low (but I don't think it's applicable since I'm not using the RCA inputs?).

The popping noise when pausing is probably a ground problem from the combination of the devices.

 

[ziggurcat]

The popping noise when pausing is probably a ground problem from the combination of the devices.

I do not have an issue with grounding as neither the Topping PA3s I have or the PA5 II exhibit that behaviour, and they have both been at the end of the same chain (there's also no buzz, hiss or hum coming from anywhere). And the fact that it's volume-dependent (if I lower the volume, the popping is quieter) doesn't scream ground issue to me? I can even turn up my other amps louder than what the A7 was, and there's zero popping.

I will find out when I do more testing with going directly from the DAC to the amp. I am going to do my best to perform my due diligence, and rule out all of the other equipment. I will even entertain the idea of connecting everything via RCA instead to rule out the cables themselves.

 

[Roland68]

I do not have an issue with grounding as neither the Topping PA3s I have or the PA5 II exhibit that behaviour, and they have both been at the end of the same chain (there's also no buzz, hiss or hum coming from anywhere). And the fact that it's volume-dependent (if I lower the volume, the popping is quieter) doesn't scream ground issue to me? I can even turn up my other amps louder than what the A7 was, and there's zero popping.

I will find out when I do more testing with going directly from the DAC to the amp. I am going to do my best to perform my due diligence, and rule out all of the other equipment. I will even entertain the idea of connecting everything via RCA instead to rule out the cables themselves.

Does the A7 also make a pop when plugged into a power outlet/strip by itself, without any additional XLR or RCA connections—just the A7 and the speakers?
Is the pop still volume-dependent?

 

[ziggurcat]

Does the A7 also make a pop when plugged into a power outlet/strip by itself, without any additional XLR or RCA connections—just the A7 and the speakers?
Is the pop still volume-dependent?

There would be no way to test whether any pop occurs with just the amp plugged in, and nothing else connected because you've removed the ability to play any audio through the amplifier. This is not a case of random pops happening while the amp is sitting idle, which is why it is not a grounding issue.

The pops occur when audio is paused (i.e. when playing music from my Mac's Music app -- it probably also occurs if I were to trigger a system notification sound, or paused a YouTube video). And it's two pops, about 0.5 to 1s after the audio has stopped -- consistently, every time. I also want to stress, again, that this does not happen with any other power amplifier I've used in the same system with the same cables, same connection chain, etc...

Edit: I've attached a link to an audio file to demonstrate the issue... please let me know if there are any issues accessing the file.

New-Recording.mp3

drive.google.com

At 3 seconds, you will hear the first mouse click starting the audio, at 16 seconds, you will hear the second mouse click pausing the audio, and shortly after you will hear two pops.

Edit 2:

So I have gone through a variety of different tests, and this was the results:

- I disabled auto sensing on the A7: same results (two pops after pausing)
- I then connected the A7 directly to a different DAC -- the Topping E50 -- via TRS: same results
- I then connected the A7 to the E50 with different balanced cables (TRS to XLR), slightly different results: One audible pop after pausing sitting 2 feet away (I did not listen with my ears any closer, but I bet there was a second pop that wasn't as audible)
- I then connected the A7 to the E50 via RCA: no audible pops sitting 2 feet away**
- I then reconnected the A7 to the regular chain (D50 III to L50 HPA to A7, all via TRS), and changed the output level on the D50 III from 5v to 4v: same results (two pops after pausing)
- I then connected the A7 directly to the D50 III DAC via RCA: no audible pops sitting two feet away**

** no audible pops when 2 feet away, but there was the faintest of ticks when I had my ear within 3 inches of the speakers. And honestly, if that was the result with the balanced connection, I wouldn't actually care because the tick with the RCA connection is so minuscule that sitting at my normal distance, it wouldn't have even been noticed.

I performed all of the same tests above with my Topping PA5 II amplifier, and there wasn't the slightest pop, tick, etc...

Sadly, based on all of this, I must come to the conclusion that the A7 amplifier needs to be returned. Another thing I discovered is that when connected via RCA, the RCA gain switch on the back of the amplifier does absolutely nothing. There is no change in the gain level switching from L to H (Low to High). I don't know if it's defective, or if that's normal functionality?

I would still like to hear a response feedback from @3eaudio on this.

 

[3eaudio]

@ziggurcat can't access your file.

 

[ziggurcat]

@ziggurcat can't access your file.

Please try again - I should have given the permissions, now.

Edit: also just changed permissions so that anyone can access... hopefully that works!

Also, in case it was missed, I posted the results of the testing I conducted.

 

[xanalog]

... A word of advice for @3eaudio -- Can you please make it so that the volume bypass switch isn't enabled by default? ...

I should have read this before I set mine up earlier today.
The [brand-less] A7 included a 48V/10A GaN brick and w/the corrected rear panel silkscreen.

Mine was an audiophonics (France) purchase, for $377.05, plus $35.22 (ship to USA)
No VAT, no tariffs, and no tax.

The amp seems to run a bit warmer -its bottom; more so- than its brick but neither is hot to the touch.
Both will be running 24/7, hidden in non-ventilated but separate compartments of an entertainment center.
I added 5mm rubber feetsies to elevate the brick and the amp will sit on a large heat-sink plate.
I added 2 ferrite beads to my new GaN brick, as welcome gifts... and did not make fun it for arriving with a 2-prong European AC wall-plug.

 

[ziggurcat]

I should have read this before I set mine up earlier today.
The [brand-less] A7 included a 48V/10A GaN brick and w/the corrected rear panel silkscreen.

Did you have a bit of a jump scare because of the unexpected volume level, panic, then a scramble to hit pause as you miss the pause button a few times, too?

(and then comfort your cat for 20 minutes because the sound scared the living crap out of him?)

 

[Good Vibes]

I had just made the decision to purchase the A7 but the issue with pops has made me hesitant. Does anyone know if this is a common issue?

 

[ziggurcat]

I had just made the decision to purchase the A7 but the issue with pops has made me hesitant. Does anyone know if this is a common issue?

I don't think I have seen anyone else mention this. Still waiting to hear from @3eaudio 's feedback. Either I got a bad unit (which happens), no one else has cared enough about it to bring it up or they are using the RCA inputs -- my tests showed to almost eliminate it completely.