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

[rvsixer]

The great thing is that you don‘t need any acoustic conditioning in the room itself. It really is quite fascinating, how I can listen without room modes, regardless of the room size. My living room is approx 20 square meters, no curtains a door permanently open to the hallway, two sideboards and a sofa. I have also exhibited the system with this relatively small speaker in a shopping center. I got so many compliments on the sound quality and diffusion of the sound. Some people on the escalators were looking to the ceiling, looking around. They could not understand where the sound was coming. The guy who asked to play Macho City a little louder (70 dB or so) had tears of laughter watching these people who were so confused about the origin of the sound.

Edit:
I also had a client recently who bought a second hand Monitor 232 from Germany. He was fascinated by the concept and who also spoke to the inventor Walter Schüpbach to ask him explain the secret of how it works, and neutralizes any room modes. He got the just of it and still perplexed and fascinated, explained it t an accoustic engineer, who believes this Quantum play that seems to be part of the equation, believes this technology is still today 20 years ahead of its time today. The original Stereolith won the Geneva Inventor exhibition back in 1987 or so.

Ahhh...so the laws of physics have indeed not changed, only the snakes.

 

[LeStereolith]

Ahhh...so the laws of physics have indeed not changed, only the snakes.

It’s understandable that you would think that, its sounds too good to be two (true) No, it is not snake oil, and no its not easily copied either. I cannot explain why or how it works, (it also has to do with the settings of the pass filters in the Stereolith). It really is hard to explain., only hearing it live will make you realize that it really has these unique features, and honestly sound just as present as if you had two large floor speakers in the room. Incidentally this speaker was built and distributed by Studer Revox, back in the day. In a short time they sold 15000 units worldwide. It was called the Duetto.
Exceptionally a photo of my living room. It about 3.5M deep and 4.5M wide. Tricky conditions, yet the sound, sound stage etc. are still formidable.

 

[antcollinet]

I cannot explain why or how it works,

Mysterious.

Possibly because:

The man is a genius and he mentions something about esoteric atomic states that remove the sound nodes.

Oh, no, wait.... that is utter nonsense.

 

[jlx]

Mysterious.

Possibly because:



Oh, no, wait.... that is utter nonsense.

aren't there forum rules against a shill coming into a forum, going off topic and trying to convince us that there is a magic speaker with magic powers that he also happens to sell???

 

[AdamG]

aren't there forum rules against a shill coming into a forum, going off topic and trying to convince us that there is a magic speaker with magic powers that he also happens to sell???

Has been dealt with.

 

[Deleted member 72219]

This is literally the worst forum on Earth to be coming in with speakers like those.

 

[jlx]

Has been dealt with.

my humble thanks for your timely efforts sir.

This is literally the worst forum on Earth to be coming in with speakers like those.

without a doubt! But maybe we just don't understand those "esoteric atomic states"..I can't read that without laughing

Ahhh...so the laws of physics have indeed not changed, only the snakes.

just brilliant...so good that I will be quoting this forever.....or until I bite the dust, whichever comes first

 

[rvsixer]

Exceptionally a photo of my living room. It about 3.5M deep and 4.5M wide.

View attachment 430294

Nice room. I can pretty much picture the frequencies and where it will have the strongest room modes (as every room does), and some will likely be exceptionally strong. Take the measurements as suggested, and you will see them too. Simply no getting around physics, the sound you hear is a BTEP.

 

[ekpln]

Hi @3eaudio ,

I have a question about your sound quality classification for A5, A7 and A7 mono. Why did you give 4 stars for the A7 when you gave 5 stars for the A5 and A7 Mono? I understand that the design and OpAmps are the same for all 3 amps. But why this difference?

 

[C0mbat]

Hi @3eaudio ,

I have a question about your sound quality classification for A5, A7 and A7 mono. Why did you give 4 stars for the A7 when you gave 5 stars for the A5 and A7 Mono? I understand that the design and OpAmps are the same for all 3 amps. But why this difference?

View attachment 435561

Yep. Logic would surely dictate that the only difference is power, which is a different category in the table.

 

[3eaudio]

@ekpln as listed, audio performance is different in terms of noise, THD, crosstalk,Max power, these part are not only related to opamp but the TPA32xx itself and PFFB implementation.
for example TPA3251 born with best audio performance w/ or w/t PFFB.

 

[antcollinet]

@ekpln as listed, audio performance is different in terms of noise, THD, crosstalk,Max power, these part are not only related to opamp but the TPA32xx itself and PFFB implementation.
for example TPA3251 born with best audio performance w/ or w/t PFFB.

Interesting.

Are you saying some of the amps in the table (Eg A7) don't have PFFB? This would be really important to know. Can you tell us which ones have PFFB

Thanks.

 

[harkpabst]

Interesting.

Are you saying some of the amps in the table (Eg A7) don't have PFFB? This would be really important to know. Can you tell us which ones have PFFB

Thanks.

That would surprise me a lot. After all, the entire product series is referred to as "A5x A7x Series Next-Gen PFFB Amplifier".

Finished Amp | 3e Audio

www.3e-audio.com

I had read that as "the TPA3251 performs a little better than the TPA3255, no matter if PFFB is implemented or not". But yes, when taken literally the statement is ambiguous.

 

[ekpln]

TPA3255 has higher THD as we know. As I guess, A7 stereo and A7 mono have higher THD than A5. But A7 Mono has better crosstalk and channel seperation than others.

For this reason, A7 Mono and A5 are given 5 stars each. But I think this is not a disadvantage for the A7 and maybe it should have been given 5 stars too.

Of course, @3eaudio will make the most accurate explanation. If there is something beyond my explanation, it would be good to know. For example, is there a difference between the PFFB implementation in A7 and A5/A7Mono?

 

[Crook]

Hi, I purchased an A7 in the current batch, I play music only at least at medium volume, so shut off should not be an issue. Automatic turn on might be an issue for me though. A7 will be fed by a preamp that also feeds an L30ii headphone amp. I currently just turn the speaker amp off when listening with headphones. Can I turn the A7 off? Will it turn on and feed the speakers when I listen through my headphones? If it does, I assume a smart plug would work to turn off the A7 at the socket? Looking forward to the A7, but this on/off situation looks to be poorly thought through to me!

 

[Guddu]

Hi, I purchased an A7 in the current batch

Congrats.

A7 will be fed by a preamp that also feeds an L30ii headphone amp. I currently just turn the speaker amp off when listening with headphones. Can I turn the A7 off?

It can be turned off using front knob, but it will more likely be turned ON when signal is detected if auto sense is enabled (which can be disabled in new version as @3eaudio mentioned).

Will it turn on and feed the speakers when I listen through my headphones?

Most likely it will.

If it does, I assume a smart plug would work to turn off the A7 at the socket?

Yes, it will work.

 

[Crook]

I would want to disable auto sense if I can. I like to just turn on and turn off my equipment manually, I can check volume levels prior then, so no nasty surprises at the speakers. I bought yesterday, so hopefully I get new version with this implemented. If not, a smart plug it is. Thanks for your advice, appreciated. Mark.

 

[hongze]

Just got my A7 last week and I am having an issue with volume control. My intension is to listen at a low volume using this amp. However, the volume control range is so limited that I either get no sound or very loud from 7 o'clock (start) to less than 8 o'clock. The very limited low volume does not give a full sound at all. When playing loud, it sounds great though. I played with the gain switch which make no difference. Any suggestions? Should I have go with A5?

My setup is:
Respberry PI (Moode at Fixed output) -> SMSL po100 -> SMSL SU-1 -> A7 -> B&W DM 303 (88db).

This setup works well with Fosi V3.

 

[Guddu]

Just got my A7 last week and I am having an issue with volume control. My intension is to listen at a low volume using this amp. However, the volume control range is so limited that I either get no sound or very loud from 7 o'clock (start) to less than 8 o'clock. The very limited low volume does not give a full sound at all. When playing loud, it sounds great though. I played with the gain switch which make no difference. Any suggestions? Should I have go with A5?

My setup is:
Respberry PI (Moode at Fixed output) -> SMSL po100 -> SMSL SU-1 -> A7 -> B&W DM 303 (88db).

This setup works well with Fosi V3.

are you controlling volume on your DAC source as well?

P.S. Just realized SU-1 does not have volume control. I guess the best option is to have A7 set to a bit higher and control volume on source to get to desired level.

 

[hongze]

are you controlling volume on your DAC source as well?

P.S. Just realized SU-1 does not have volume control. I guess the best option is to have A7 set to a bit higher and control volume on source to get to desired level.

Guddu, thank you for your comments.

I used the software volume control in Moode but feel (not scientifically) that the sound quality is not as good as fixed from Moode and controlled with A7. I am still evaluating and will try my other speakers. I have a pair of Dali oberon 5 to try when I have time but it is also at 88db sensitivity.

The question again:

Does the A5 have a lower gain when controlled by its volume knob?