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Fosi Audio V3 Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 11 3.0%
  • 2. Not terrible (postman panther)

    Votes: 32 8.7%
  • 3. Fine (happy panther)

    Votes: 185 50.3%
  • 4. Great (golfing panther)

    Votes: 140 38.0%

  • Total voters
    368

Verig

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May 4, 2023
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For you yes. Why would you understand IC manufacturing?
You could guide me (and many others) to some references how it works. Perhaps with some images to go. I fully appreciate that things are not always as they seem but asking why would I understand is not very fruitful.
You're saying that we can't be sure by looking or by measuring. So there is no way to know what is real/licenced and what is not? Perhaps, I have no problem with the general idea. But why would I take your word for it?
 

peng

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That's not what happens with real speakers. This is what happens with real speakers, it will vary with load but this is what I got from an aiyima a07. I tested three a07's and got different rising responses towards the top end with each one but similar behavior of things starting to rise around 5khz (just the tweeter here and it's passive network, c note speaker).

While I'm not a big fan of the youtuber Andrew Robinson, he put out a video documenting the same problem, but he wasn't sure what the cause was, just that he was getting totally different HF responses with different amplifiers.

View attachment 293761

Same tweeter with amp that doesn't have load dependency (had woofer connected for this one, can ignore below 2k,). This seems like a good opportunity to market "non-load dependant" amplifiers from the budget amp makers. I've had people tell me it's just these speakers that an outlier, nope found plenty of commercial offerings with very similar impedence charts, like kef q150. Most people are pairing these speakers with cheap amps, I wonder how many complaints about brightness are because of this issue. I will continue to rate any amplifier with this issue as poor as I don't consider it acceptable and it is a design flaw in my eyes.

View attachment 293762

I measured my different apeakers with different amps, never experienced what Robinson did. He seems to be a 100% subjectivist so I am very surprise he would bother measuring FR or anything, so I don't know what to say about his measurements, at least not until I watch that video. In theory, as long as the amps have low enough output impedance, such as damper factor of between 50 and higher, even 50 vs 1000, in the audio band, it should not affect the anechoic FR of a speaker by more than a couple dB. But then, people like Robinson will never trust theories, specs and measurement more than what he thinks he heard. He obviously is the typical trust the ears only type.
 

Colonel7

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It has nothing to do with measurements. The product description and the actual product should not be different.
Agreed! Additional concern that I have is that over time more and more parts are counterfeit and the device doesn’t test the same performance-wise. Weirdly, this could mean get it now to be closest to Amir’s testing.
 

Bicep

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Jun 24, 2023
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It has nothing to do with measurements. The product description and the actual product should not be different.
I got the amp and think it sounds good, but if I didn't get what I paid for component wise I'll return it if Fosis response is not very satisfactory. I mostly got the amp because Fosi has impressed me with their surveys and continuous progress, and if it turns out they use other parts than those advertised and don't take action to do it right my trust in them will be gone for a long time. Then I'd rather get products from other companies.
 

Toku

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I changed the attached 32V power adapter to the 48V power supply of MeanWell LRS-200-48 and tested the heat generation of Fosi Audio V3.

I ran it continuously for about 5 hours in an environment where the room temperature was 25°C in early summer, but the V3 was only slightly warm, and I didn't feel the big heat generation like the AIYIMA 07 at all.
The improved heat dissipation structure seems to effectively dissipate heat throughout the case. Also, when I put my finger close to the ventilation holes in the case, I can feel the air flow slightly warmer than the case, so I think this is also working effectively.
In this case, it seems that it can be used safely at 48 V even in an environment with a room temperature of 28 ° C in the middle of summer.

I also found the data of the inductor for the filter used in V3.

 

TheBatsEar

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Will my V3 measure and sound the same as those units reviewed?
That is likely.

Why hasn't Fosi Audio weighed in on this issue as it appears the company follows this forum?
I would say the weekend is a factor. ;)
The guys at Fosi have to get aware that there are question, look into it and then communicate about it. This takes time in the corporate world.

Anyway, welcome to ASR :cool:
 

RTFM

New Member
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Mar 9, 2023
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Just did the same order from the UK. Total 98 GBP with free shipping
 

Ultratek

Member
Joined
Apr 8, 2023
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32
For a moment I thought this was a forum for Audio fans, am I wrong?

Subjective opinions and not verified until now.
The V3 has dummy Opamps/. It is not proven or difficult to verify.
The V3 has dummy inductors. It is NOT proven/difficult to verify.
The V3 has dummy capacitors. It is not proven/difficult to verify.

The verified facts are:
Does the V3 work well?: If so, it's checked!
The V3 has an efficient heat dissipation design? if so, it is verified
Does the V3 have a good/recommended sound quality? If so, it is verified!
The V3 feels quality! If so, it is verified!
Could the V3 be considered Chi-Fi? If so, it's checked!
The V3 has a very good price? If so, it's proven!
Would the V3 be, if not the best, one of the best amps in its price range? If so, it's checked!

The rest are already discussions that do not concern the loudness or audio quality verified by not only amirm but also many more in this forum and other websites.
I would think that this site is not a web of morality and civility. neither the opposite.
Simply and pleasantly it is Audio Science Review.

My intention is not to discredit or criticize anyone, just to get out of this loop and return to the enriching comments with which I am accustomed.
Cheers Friends!
 

Talisman

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Yet another dull $10 (manufacturing cost) box.
Yet another dull TPA3255, there are thousands PCBs based on this IC on alibaba and elsewhere.
Yet another "sudden event" of counterfeited components.
And there are not a single idea, not a single thought, not a single glimpse of novelty, only the cheap labor of unknown Chinese solderers, assemblers and packers.
Welcome to the endless boredom and despondency or a "new audiophilia world", God forgive me.
Superfluous and ridiculous comment. Thousands of these boxes are present on Chinese stores, and I'm willing to bet that they have mediocre or even poor performance with botched implementations.
Fosi Audio have implemented this chip to best performance levels ever measured for these little 3255 boxes and have certainly produced the best amplifier under 100 Euros ever tested here, on top of that they have solved the problem of overheating and provided suitable power levels to 90% of home audio applications.
Are you bored?
Grab one of the many anonymous 3255 boxes for sale in AliExpress and good luck.
 

Valvetubehead

Member
Joined
Jun 3, 2023
Messages
52
Likes
83
For a moment I thought this was a forum for Audio fans, am I wrong?

Subjective opinions and not verified until now.
The V3 has dummy Opamps/. It is not proven or difficult to verify.
The V3 has dummy inductors. It is NOT proven/difficult to verify.
The V3 has dummy capacitors. It is not proven/difficult to verify.

The verified facts are:
Does the V3 work well?: If so, it's checked!
The V3 has an efficient heat dissipation design? if so, it is verified
Does the V3 have a good/recommended sound quality? If so, it is verified!
The V3 feels quality! If so, it is verified!
Could the V3 be considered Chi-Fi? If so, it's checked!
The V3 has a very good price? If so, it's proven!
Would the V3 be, if not the best, one of the best amps in its price range? If so, it's checked!

The rest are already discussions that do not concern the loudness or audio quality verified by not only amirm but also many more in this forum and other websites.
I would think that this site is not a web of morality and civility. neither the opposite.
Simply and pleasantly it is Audio Science Review.

My intention is not to discredit or criticize anyone, just to get out of this loop and return to the enriching comments with which I am accustomed.
Cheers Friends!
Too much critical thinking for some. Enjoy it for what it is or isn’t … bargain hunters are often the pickiest.
 

Talisman

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I ran it continuously for about 5 hours in an environment where the room temperature was 25°C in early summer, but the V3 was only slightly warm, and I didn't feel the big heat generation like the AIYIMA 07 at all.
The improved heat dissipation structure seems to effectively dissipate heat throughout the case. Also, when I put my finger close to the ventilation holes in the case, I can feel the air flow slightly warmer than the case, so I think this is also working effectively.
In this case, it seems that it can be used safely at 48 V even in an environment with a room temperature of 28 ° C in the middle of summer.
My experience has been quite different.
I played music at low and medium volume for several hours, temperature similar to yours, around 25 degrees, enough space around and no other electronics above/below the V3.
To the touch very warm amplifier.
I didn't bother because for the type of design the case should be used as an active component in the dissipation, but I don't understand the discrepancy at this point.
 

notsodeadlizard

Senior Member
Joined
Feb 18, 2023
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340
Superfluous and ridiculous comment. Thousands of these boxes are present on Chinese stores, and I'm willing to bet that they have mediocre or even poor performance with botched implementations.
Fosi Audio have implemented this chip to best performance levels ever measured for these little 3255 boxes and have certainly produced the best amplifier under 100 Euros ever tested here, on top of that they have solved the problem of overheating and provided suitable power levels to 90% of home audio applications.
Are you bored?
Grab one of the many anonymous 3255 boxes for sale in AliExpress and good luck.
They are all exactly the same because this chip is a functionally complete amplifier.
You can use input buffers in a circuit with it, you can not use it because the input impedance (20K) and maximum input voltage (7V) are de facto standard because TI is very good at designing microcircuits and knows the market very well.
This nonsense is very difficult to spoil, this is a microcircuit for mass production of cheap equipment where it is not customary to strain especially.
Here, for example, is one of the innumerable decently assembled boards:
They are all exactly the same...
 

Talisman

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They are all exactly the same because this chip is a functionally complete amplifier.
They are not, just look at the aiyima a07 or fosi tb10d measurements.
you are talking nonsense.

If it was that simple to implement a chip into a full integrated amplifier I didn't need Amir and measurement sites
 
OP
amirm

amirm

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Here, for example, is one of the innumerable decently assembled boards:
https://nl.aliexpress.com/item/1005...sjlvh7GRcdgwaXedruFREeTY&gatewayAdapt=glo2nld
Those are the ones with heat issues. That heatsink inside a box is not going to be able to breath. Fosi has put the IC on the other side and coupled it with an aluminum block to the case. Your sample there also seems to lack input buffer/volume control. Had it have a volume control, it would have likely be a lousier feeling one than Fosi. It also lacks case and power supply.
 

notsodeadlizard

Senior Member
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Feb 18, 2023
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They are not, just look at the aiyima a07 or fosi tb10d measurements.
you are talking nonsense.

If it was that simple to implement a chip into a full integrated amplifier I didn't need Amir and measurement sites
It's unbelievable but it's true:
And all measurements are in the datasheet and it is difficult to say what else can be measured.
Well, OK, measurements of different assemblies are interested in a sense of "How the reference design can be mess up?".
Although the microcircuit is made for decent manufacturers who strive for datasheet parameters.
 

howard416

Active Member
Joined
Sep 12, 2019
Messages
208
Likes
117
For a moment I thought this was a forum for Audio fans, am I wrong?

Subjective opinions and not verified until now.
The V3 has dummy Opamps/. It is not proven or difficult to verify.
The V3 has dummy inductors. It is NOT proven/difficult to verify.
The V3 has dummy capacitors. It is not proven/difficult to verify.

The verified facts are:
Does the V3 work well?: If so, it's checked!
The V3 has an efficient heat dissipation design? if so, it is verified
Does the V3 have a good/recommended sound quality? If so, it is verified!
The V3 feels quality! If so, it is verified!
Could the V3 be considered Chi-Fi? If so, it's checked!
The V3 has a very good price? If so, it's proven!
Would the V3 be, if not the best, one of the best amps in its price range? If so, it's checked!

The rest are already discussions that do not concern the loudness or audio quality verified by not only amirm but also many more in this forum and other websites.
I would think that this site is not a web of morality and civility. neither the opposite.
Simply and pleasantly it is Audio Science Review.

My intention is not to discredit or criticize anyone, just to get out of this loop and return to the enriching comments with which I am accustomed.
Cheers Friends!
Would it not be very easy to verify that the marketing of this product is fraudulent?
 

dr_mick51

Active Member
Joined
Mar 12, 2022
Messages
180
Likes
179
These little OP amp chips are just Eprom chips I could rig up something and programme the data and store it. By changing the data its uniquely my chipset that anyone can copy. Just like people who change Engine ECUs for fuel, oxygen & detonation timmings. Exactly same results too lean, too rich, kill the engine quicker!
Quality of the ic's and everything surrounding it is way more important to me.
These are operational amplifiers (op amps) not microprocessors. They don't have firmware/microcode nor memory. You cannot program an opamp to custom it to the sound you prefer.
What you talk about seems to be more like dsp.
 

dr_mick51

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Mar 12, 2022
Messages
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Yet another dull $10 (manufacturing cost) box.
Yet another dull TPA3255, there are thousands PCBs based on this IC on alibaba and elsewhere.
Yet another "sudden event" of counterfeited components.
And there are not a single idea, not a single thought, not a single glimpse of novelty, only the cheap labor of unknown Chinese solderers, assemblers and packers.
Welcome to the endless boredom and despondency or a "new audiophilia world", God forgive me.
True. But you are missing important points:
At this price point you will not get a better performing amplifier. You have tests and measurements that back it up.
Yes, I've seen other boards with the same chipset some way more expensive and in the end you need to buy your aluminum enclosure and add other conectores, speaker terminals, switches, etc...
The other important point to mention is this amplifier was measured and got this kind of performance by using the already mentioned components(opamps, inductors, capacitors) which most of us agree they(Fosi Audio) could have done better. But for this price point I don't complain. I'm just planing to get parts from Digikey or Mouser and modify it.
All these Chinese audio brands do the same. For me it's not a surprise. That's the price we pay. Is it correct? Probable not. I don't care. If I'd had the money I'd buy better and more expensive amps. Until then this is what I can get.
 
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