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Best Ti3255 Amplifier >>>Aiyima? Fosi Audio? O-Noorus?

Audionaut

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Hello everyone,

I'm looking for the best amplifier with a Ti3255 chip in terms of sound quality, although I assume that the protagonists mentioned below won't be much different in practice.
Questions I am also asking myself >>>
Is PFFB necessary and which power supply is the best?
Do only watts and amps play a role in the power supply or are there other things that should be considered? The following candidates are on my list, but I don't want to buy them all:

Aiyima A70 Stereo and Mono
Aiyima A80
Fosi Audio V3 Mono
Fosi Audio ZA3
O-Noorus D1 D3 (D4?)

Are there any other suggestions?

Is it possible to connect a power supply from e.g. Aiyima to a Fosi without any problems or are the connections different? Are the power supplies compatible with the different amplifiers?

I don't trust the power supply connections so much because I find the plug connections too weak and unsafe for the voltages applied.

I like the Fosi Audio ZA3 best in terms of housing, but it lacks PFFB, although many websites emphasize its sound as formidable.

I don't really need a built-in DAC or many functions, because preamplification and streaming is done via the WiiM Ultra.

I'm currently leaning towards the Aiyima A70 in the stereo version with a 48V 10A GaN power supply, although I'm not a big fan of its design.
 
I recently purchased the O-Noorus D1 and have been impressed so far with its performance. I using mine with the WiiM Ultra. There are separate threads on this forum for most or all of the models you are asking about. These should provide more specific product information. Good luck!
 
There are separate threads on this forum for most or all of the models you are asking about. These should provide more specific product information. Good luck!
Thanks

Yes, that's right - and I probably know them all.

But the question of the compatibility of the power supply and its effects on the sound is not answered there, nor is the question of whether PFFB makes an audible difference in comparison.

I think maybe there are a few people here who have the opportunity to hear these amplifiers in comparison because they have them at home.

Unfortunately, there are still no conclusive tests and reviews on the O-Noorus D4.
 
I have tried 3 different power supplies with my D1 and I have a fourth on the way. I will post my experience with these in the D1 impression thread when I am finished listening to them. I do believe that each of these different TPA 3255 implementations have a power supply "sweet spot" that balances volume, distortion and heat for that particular unit.
 
Yes, 3e's ready-made appliances also seem to be very well designed.

My favorite would be a Fosi ZA3 with PFFB and a 48V 10A GaN power supply.

I like the design and mechanical construction of the ZA3 best.

I also think the Aiyima A70 is well constructed, but the design is not my cup of tea.

In my opinion, the Aiyima A80 buys its features with disadvantages in terms of clean signal processing.

I think the 3e series is still a bit ambitious in terms of price.
In Germany, a stereo 3e with TPA3255 and power supply is almost twice as expensive as an Aiyima A70 stereo, which has pretty much the same specifications.
 
Hello everyone,

I'm looking for the best amplifier with a Ti3255 chip in terms of sound quality, although I assume that the protagonists mentioned below won't be much different in practice.
Questions I am also asking myself >>>
Is PFFB necessary and which power supply is the best?
Do only watts and amps play a role in the power supply or are there other things that should be considered? The following candidates are on my list, but I don't want to buy them all:

Aiyima A70 Stereo and Mono
Aiyima A80
Fosi Audio V3 Mono
Fosi Audio ZA3
O-Noorus D1 D3 (D4?)

Are there any other suggestions?

Is it possible to connect a power supply from e.g. Aiyima to a Fosi without any problems or are the connections different? Are the power supplies compatible with the different amplifiers?

I don't trust the power supply connections so much because I find the plug connections too weak and unsafe for the voltages applied.

I like the Fosi Audio ZA3 best in terms of housing, but it lacks PFFB, although many websites emphasize its sound as formidable.

I don't really need a built-in DAC or many functions, because preamplification and streaming is done via the WiiM Ultra.

I'm currently leaning towards the Aiyima A70 in the stereo version with a 48V 10A GaN power supply, although I'm not a big fan of its design.
You should also add the TPA3251.
In my personal experience, although I have also heard the ones you listed, random order:
Sylph Audio
3E Audio
XRK Audio
Topping PA5 & PA5 II (Plus)
However, the others are also very good.
But in the end, you have to like it and the price has to be right. If you don't like the look of it, you'll keep looking, otherwise you'll have a construction site.

I'm not a fan of the plugs either, but these are the exact plugs that are used in IT to transmit up to 400 watts as a continuous load, 24/7 for years. I have changed my external DC connections on amplifiers/power amplifiers to XT 30/XT 60 plugs, there are also 3-pin ones for +/- voltages.

In my personal experience, the best power supplies for single DC amplifiers are Mean Well HRP/N/N3, available in all power classes.
 
Hello.

Regarding the current models of class D amplifiers equipped with ONE TEXAS INSTRUMENTS TPA3255 chip and in view of the format and material of their housing, which therefore only allow a 'limited' heat dissipation, a 42V/8.3A power supply seems to me to be the most appropriate for a 'contained heat' and a 'comfortable power'.

For the other models equipped with ONE TEXAS INSTRUMENTS TPA3251 chip, I think that what TOPPING has proposed with its PA5 II plus amplifier (38V-4A power supply) corresponds exactly to the criteria I mentioned above for the other amplifier chip.

It is also worth noting that the TOPPING 38V/4A power supply has excellent characteristics.

Kind regards.
 
I replaced my Icepower 250ASX2 dual mono setup with a pair of Fosi Audio V3 monos with individual 48V10AGaaN Aiyama supplies. I am very happy with the results. I originally had the package from Fosi with a single 48V 10A supply and DC filter but there were a number of issues with that config. I have each mono block in very close proximity to the speaker it is driving and I use single-ended line from the preamp (Wiim Ultra).
 
Im waiting for the Onoorus D3 Pro with PFFB which is probably coming out early next month. That might be a suggestion. I made a whole Excel sheet with all the options and for me Onoorus has the best looks and connectivity options.
I do wish Onoorus is getting a proper review soon.
 
Yes, 3e's ready-made appliances also seem to be very well designed.

My favorite would be a Fosi ZA3 with PFFB and a 48V 10A GaN power supply.

I like the design and mechanical construction of the ZA3 best.

I also think the Aiyima A70 is well constructed, but the design is not my cup of tea.

In my opinion, the Aiyima A80 buys its features with disadvantages in terms of clean signal processing.

I think the 3e series is still a bit ambitious in terms of price.
In Germany, a stereo 3e with TPA3255 and power supply is almost twice as expensive as an Aiyima A70 stereo, which has pretty much the same specifications.
The A70 was tested by Amir, and for an PFFB design, it stinks. -100 dB 2nd and -103 dB third harmonic at 1 kHz / 4 R / 5 W. Well-implemented non-PFFB almost got there, and the Fosi V3 Mono, arguably on of the poorer implementations, sports -115 / -120 dB. The Fosi measured worse in 19 / 20 kHz IMD (-80 dB for A70, -68 dB for V3 Mono). I am not sure what the reason is (lower PFFB bandwidth, coils with poor HF performance) or whether it is real at all: archimago got -82 dB for the Fosi at 1 W, and for all other amps tested by both, IMD results are usually very close in spite of the the different power settings used.

I would probably rate them like this for distortion performance (top to bottom)
PA5
PA5 II
A5
A7, PA7, likely also 260A-2-29A (need to compare graphs)
D1 (there are a few measurements by a Ukrainian gentleman out there)
V3 Mono
A70

The Sylphaudio D100 was also measured by Amir. It is pretty high up in the list, but not at the very top. The newer FB100 is probably at the very top, I just haven't seen measurements yet. I am not aware of what XRK does, maybe need to take a look.
 
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strangely enough i dont think we're there yet, even in 2025!

i think people are after a simple stereo amp with perhaps a vol. ctrl. at most and say 75-90w - as people above say, a PFFB Fosi V3 would do it.

Right now there's only the V3 Mono, if you can handle two boxes, the PFFB O-Noorus D1 but that is at yet untested.

The 3e looks ok but only 60w and at that price you may as well go Fosi V3 Mono.
 
strangely enough i dont think we're there yet, even in 2025!

i think people are after a simple stereo amp with perhaps a vol. ctrl. at most and say 75-90w - as people above say, a PFFB Fosi V3 would do it.

Right now there's only the V3 Mono, if you can handle two boxes, the PFFB O-Noorus D1 but that is at yet untested.

The 3e looks ok but only 60w and at that price you may as well go Fosi V3 Mono.
I have both the O-Noorus D1 and a pair of Fosi V3's. Listening to them back to back, they sound very similar with the V3's being more powerful and providing slightly better bass with my inefficient tower speakers. Both are dead quiet. For the money, I don't think you can go wrong with either of these. Unless you have very power hungry speakers or need balanced inputs, the O-Noorus D1 with its subwoofer out, digital volume control, tone controls and remote is an incredible value for the money.

It is refreshing to have so many great sounding (and measuring) choices in this price bracket. The ease of opamp replacement is just icing on the cake.

Longevity is still an unknown, but so far, so good.
 
My vote is for O-NOORUS. I hope one day they release a model that has sub-out with high pass filter and auto on/off feature. I'll buy that one immediately.
 
Hello @AIYIMA,
Is that a typo or reality?

1000022023.png

Is 20 - 80Hz the range of the subwoofer's control or actually 200 - 800 Hz, which would be absolutely nonsensical?

One more question: Why does the A70 Mono have 2 X Rubycon 3300 microfarad and the A70 Stereo only 2 X 2200 microfarad, although it has to supply one more channel?

1000022024.png
 
Maybe they had the room in the box or they figured a mono would be mainly used for driving subs? Many of these amps have less power at 20 Hz than they have a little higher up because the local reservoir is too small
 
I'd just use the one that has the features you want/need and nothing more and call it a day. For me, I just want plain amps with nothing else but balanced/unbalanced inputs and some sort of auto power function. Fosi V3 Monos for me.
 
Would wait for the O-Noorus D3 pro (power dac).... Will be in the market soon.
 
As I understand the soecs of the TPA 3255 chip the PFFB feature is a standard on the chip. Please coorect if I am wrong. I think Fosi didn’t have that as a priority in the marketing of the ZA 3. Let us say it is a feature you can activate then it would be clearly described in the TPA 3255 application notes. If you go mono do get the the 48v/10a bricks so you don’t run out of steam.
 
As I understand the soecs of the TPA 3255 chip the PFFB feature is a standard on the chip
That is correct.
However, most suppliers of TPA3255 amplifiers have not activated this optional feature of the chip in recent years.
As far as I can judge the market, PFFB was not established as a standard until 2024.
Douk A5 and O-Noorus D1 are currently the cheapest 3255 versions with PFFB.
 

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