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

I can see that thus would work but using the A7 monos vol bypassed as poweramps was the appeal in getting them and I'd rather not have to manually level-balance the 2 channels.
Definitely not convenient and probabt not what I wanted to do either. Just wanted to remind everybody of this obvious solution.

Luckily, my speakers are of rather medium-low efficiency (funny to say that :p) and I only use a single A5 in two of my setups.

The preferred solution would be, obviously IMHO:
- physical power switch (even though one would ideally cut off the power to the SMPS brick for a real off state).
- standby/operate switch with several positions, on / off / 12-Trigger / signal-detect, the latter maybe with 2 or 3 different sensitivities.
All true. Would definitely increase the costs,. though, and the physical switch was most suited to a design with integrated PSU.

Without any changes to the board layout, I think that reducing the sensitivity for entering standby (probably just different resistor values) and an increased delay time (MCU firmware change) would already improve the situation for many of those who are affected.
 
3e Audio,
Is it possible next time to make a finished amplifier that would be easily upgradeable? So, when in future your company releases a next generation electronic board, we users would just buy this board alone and replace it in the amplifier ourselves without the need to buy the finished amplifier again.
Is it possible to do so?
That doesn't really make sense. The board layout had to be exactly the same regarding connectors, mounting holes, heatsink placement, power connector, volume pot and so on. Too many limitations.

And that's just the beginning. How much would you expect to save in such an offer? How should support deal with those who fail to "just replace the board"?

Finally, you could already sort of do what you are after buy buying your own amplifier based on 3e Audio's DIY boards. But how many different revisions have you seen over the years?
 
Definitely not convenient and probabt not what I wanted to do either. Just wanted to remind everybody of this obvious solution.

Luckily, my speakers are of rather medium-low efficiency (funny to say that :p) and I only use a single A5 in two of my setups.


All true. Would definitely increase the costs,. though, and the physical switch was most suited to a design with integrated PSU.

Without any changes to the board layout, I think that reducing the sensitivity for entering standby (probably just different resistor values) and an increased delay time (MCU firmware change) would already improve the situation for many of those who are affected.
The simplest solution which would allow the use of the current hardware without changes would be to disable the auto On/Off functionality in the MCU software.

So maybe something really simple such as holding the volume switch for 20 seconds to toggle the Auto On/Off functionality in the software. A few lines of code would fix this issue and keep everyone happy !!
 
This might be a silly question, but I’m curious why I need to set the volume to level 30 on the A5 to achieve the same loudness as level 18 on my old Marantz M-CR603, even though the Marantz is technically a weaker device on paper. Could this difference be due to gain? I’m not complaining—in fact, I appreciate the more gradual power distribution at lower levels—but it does make me wonder if the A5 is as powerfu...

Do you usually set high or low gain?
 
This might be a silly question, but I’m curious why I need to set the volume to level 30 on the A5 to achieve the same loudness as level 18 on my old Marantz M-CR603, even though the Marantz is technically a weaker device on paper. Could this difference be due to gain? I’m not complaining—in fact, I appreciate the more gradual power distribution at lower levels—but it does make me wonder if the A5 is as powerfu...

Do you usually set high or low gain?
By 30, do you mean like 30 percent?

Yes, it's all about gain. There's no benefit in too much gain. As long as you can reach your max. desired level with the device controlling the volume (A5 or preamp) at 100% everything is perfect. Higher gain setting means higher noise, so the lowest available gain setting that fulfills the above requirement is best.

Unfortunately, many confuse gain with power and think a lower setting of the volume wheel indicates a more beefy amp. Some even "hear" with their eyes, that an amp fully cranked up must sound congested. :p
 
There is actually something wrong with this auto on/off function. Today I was listening to John Hopkins, which is rather calm instrumental music, without dynamic fragments, and it turns out that one of the A7mono turned off for a moment during a longer, quiet fragment of the song. The volume on the Wiim Ultra was set to 20, and beyond that it was not quiet at all.
By the way, I looked at the Audiophonics website and the European prices of the A5/A7 series are not very attractive. In my example, I can say that the A7mono set cost me PLN 1,258 + PLN 120 in customs and tax fees with shipment to Poland. THIS amounts to approximately PLN 700 for one piece of A7mono. If purchased from Audiophonics, one A7mono would cost approximately PLN 1,080. If I were to spend about PLN 2,200, I would probably look for a power amplifier with Hypex modules.
 
There is actually something wrong with this auto on/off function. Today I was listening to John Hopkins, which is rather calm instrumental music, without dynamic fragments, and it turns out that one of the A7mono turned off for a moment during a longer, quiet fragment of the song. The volume on the Wiim Ultra was set to 20, and beyond that it was not quiet at all.
By the way, I looked at the Audiophonics website and the European prices of the A5/A7 series are not very attractive. In my example, I can say that the A7mono set cost me PLN 1,258 + PLN 120 in customs and tax fees with shipment to Poland. THIS amounts to approximately PLN 700 for one piece of A7mono. If purchased from Audiophonics, one A7mono would cost approximately PLN 1,080. If I were to spend about PLN 2,200, I would probably look for a power amplifier with Hypex modules.
and what are your expectation with Hypex modules if you allow me to ask?
 
Got a subjective question how does the A7 sounds relative to other well measured (costly) amp's let say a Hypex NCx500 which power output is close to double ( or over). Got still a good working NAD C370. In the case the NAD will fail i was thinking to recap the NAD but current (Dutch) sky rocketing recap cost (around 1000,- euro) don't make sence if i can buy a 3e Audio A7 or comparable other amp for just under 400,- euro. Only disadvantage is that the connectivity of the NAD is second to none making use of binding post for 2 pair of speakers monitors an farfield speakers is handy for me. Any advice?
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I finally received my A5 today in India, thanks to a friend who brought it over from the USA.

I've upgraded from the Fosi V3 Stereo amp, and the improvement in sound quality is significant. The A5 is a powerhouse, delivering ample power for my system! The high frequencies feel more balanced, possibly due to the PFFB feature.

@3eaudio could you please confirm if the volume control uses a logarithmic taper A similar to the one in the Fosi V3 Stereo? 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?
 
RCA or balanced input? Make sure to use the low gain position when using the RCA inputs.

What's your source and is the output voltage configurable? If you need the volume control to be set really low this is not an indication of high power but (too) high gain (relative to the sources output voltage).
 
and what are your expectation with Hypex modules if you allow me to ask?
Clean and neutral sound, which is what characterizes good class D amplifiers, which I think includes amplifiers based on Hypex modules.
 
RCA or balanced input? Make sure to use the low gain position when using the RCA inputs.

What's your source and is the output voltage configurable? If you need the volume control to be set really low this is not an indication of high power but (too) high gain (relative to the sources output voltage).
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.
 
Clean and neutral sound, which is what characterizes good class D amplifiers, which I think includes amplifiers based on Hypex modules.
I've got NC400 and Nilai and yes, clean and neutral but for me at the same time a bit boring compared to 3e Audio modules and amps. I was really positively shocked when I hooked up my A7 monos the first time.
 
I am even more glad that I managed to buy a7mono at such a price, because I must admit that I am very pleased with the sound of the set :) Although a small failure has already occurred, the opamp in one monoblock died, it happens, probably a faulty unit. I am in the process of clarifying the situation with 3audio. I temporarily put in Burson V6 Vivid.
 
I am even more glad that I managed to buy a7mono at such a price, because I must admit that I am very pleased with the sound of the set :) Although a small failure has already occurred, the opamp in one monoblock died, it happens, probably a faulty unit. I am in the process of clarifying the situation with 3audio. I temporarily put in Burson V6 Vivid.
Just so long as something in the circuit did not kill the op amp... !
 
Don't scare me, I hope that wasn't the reason.
Much as I would hate to tear myself away if I were in your shoes, it could be a cause (I think)! Mind you the 3255 has protective circuitry (I think) ... !
Post edit ... I'd make sure with 3e ... or bung another one in there for the meantime if you have one!
 
Do you mean to check with another opamp?
something more expendable - I once put an op amp in a 3255 circuit the wrong way round (back in earlier days) ... and it was fine.
But there are surely a number of reasons why an op amp should just 'fail' like that ... it is extremely rare.

Post edit ... Bursons are not exactly cheap.
 
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.
 
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