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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 13 1.9%
  • 2. Not terrible (postman panther)

    Votes: 22 3.2%
  • 3. Fine (happy panther)

    Votes: 135 19.8%
  • 4. Great (golfing panther)

    Votes: 513 75.1%

  • Total voters
    683
This mono is riding it's brand fame. With rising distortion towards higher frequencies and such multitone results, this is not worth of golfing panther in this day and age.
I politely disagree with your assertion. It performs much better than the distinguished amplifiers that it replaced in my system and is a bargain at the price. It measures at the top end of amplifiers tested by Amir which backs up my subjective assessment.

Did you face any sort of issues following installation in your system we should know of please document them here so we might learn about them and discuss.
 
Are there any disadvantages that you are aware of (other than convenience), preventing the units just be switched on and off?
When they are on they get warm, around 40deg centigrade, regardless of what they are doing. This is the temperature of the metal vent grills. I cannot comment on life expectancy but it does feel like leaving them "running hot" might be worth minimizing.

They consume a combined total of approx.15W when on, I have not measured the consumption when they are idle in auto mode.
 
You mean in standby mode? It's high
Ah, yes. Misleading, sorry. I have the DAC / Mini PC and Monos on one energy plug. I was interested in what the combined power consumption was with music playing 35W ....versus me leaving the system on but not playing music 18W.....which I want to do as I have a multiroom LMS setup where I leave the players awake.....nice to know what the background energy consumption is. When the chief goes to bed the smart plugs are powered off so zero energy used during dream time.
 
I politely disagree with your assertion. It performs much better than the distinguished amplifiers that it replaced in my system and is a bargain at the price. It measures at the top end of amplifiers tested by Amir which backs up my subjective assessment.
That may well be true, but it's not as good as other amps in the same neighbourhood of the SINAD list or amps with the same chip. If you look at 32 tone test, 19 & 20 kHz test and power vs distortion test at different frequencies (higher than 1 kHz) (where measurement available) of this and other amps, you'll see that this mono is behind.
https://www.audiosciencereview.com/...io-p122-class-d-amplifier-measurements.11801/ (NCore)
https://www.audiosciencereview.com/forum/index.php?threads/ati-at522nc-stereo-amplifier-review.9999/ (NCore)
https://www.audiosciencereview.com/...dio-tpa3255-260-2-29a-amplifier-review.50208/ (TPA3255)
https://www.audiosciencereview.com/...topping-pa5-ii-stereo-amplifier-review.47362/ (TPA3255)

Peace.
 
Just read this from the company in their message to me when the amp was sent:

"We'll provide a bundle including two V3 mono amps and a 48V/10A psu for no more than 260USD. That single 48V/10A psu can power the two sets of v3 mono simultaneously."

How? It has a Y cable for the power? Cool.
 
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That may well be true, but it's not as good as other amps in the same neighbourhood of the SINAD list or amps with the same chip. If you look at 32 tone test, 19 & 20 kHz test and power vs distortion test at different frequencies (higher than 1 kHz) (where measurement available) of this and other amps, you'll see that this mono is behind.
https://www.audiosciencereview.com/...io-p122-class-d-amplifier-measurements.11801/ (NCore)
https://www.audiosciencereview.com/forum/index.php?threads/ati-at522nc-stereo-amplifier-review.9999/ (NCore)
https://www.audiosciencereview.com/...dio-tpa3255-260-2-29a-amplifier-review.50208/ (TPA3255)
https://www.audiosciencereview.com/...topping-pa5-ii-stereo-amplifier-review.47362/ (TPA3255)

Peace.
The P122 costs US $750.

The 522NC costs US $2,195

3e audio 260-2-29A US $109.00 = has less power

Topping PA5 II stereo US $289.50.

The neighborhoods of price or power change things for me, I'll take higher clean distortion free power with the lowest cost :)
 
What I find surprising is that the key ingredient, the TPA3255 chip from TI, has been around for… 8 (more?) years. Why did it take so long for somebody to figure out the successful recipe?
Kudos to Fosi Audio for listening to the users, and applying good engineering rather than chasing some esoteric BS audio paradigm.

Actually, the PFFB configuration was documented from the beginning. But the TPA3255 being an inexpensive chip aimed at inexpensive devices, most manufacturers were using it without PFFB to save even more.
 
This would defeat the purpose of mono blocks which is being able to keep them close to speakers with shorter speaker wire.

Not necessarily, only the PSU cable needs to be longer.
 
That may well be true, but it's not as good as other amps in the same neighbourhood of the SINAD list or amps with the same chip. If you look at 32 tone test, 19 & 20 kHz test and power vs distortion test at different frequencies (higher than 1 kHz) (where measurement available) of this and other amps, you'll see that this mono is behind.
https://www.audiosciencereview.com/...io-p122-class-d-amplifier-measurements.11801/ (NCore)
https://www.audiosciencereview.com/forum/index.php?threads/ati-at522nc-stereo-amplifier-review.9999/ (NCore)
https://www.audiosciencereview.com/...dio-tpa3255-260-2-29a-amplifier-review.50208/ (TPA3255)
https://www.audiosciencereview.com/...topping-pa5-ii-stereo-amplifier-review.47362/ (TPA3255)

Peace.
Point well made. If dyno testing equipment only is the criteria then of course no argument. There's no denying the science of measurement in that respect. However as noted there's a need for willingness to pay more and in some cases substantially more to get those slightly better numbers. And of course the results at the ear depends on upstream component and a whole other bunch of variables as to what is actually delivered. While measurements may be more impressive my ear is insufficiently golden to notice the numbers. They are to my way of thinking indicative only and a good guide to what is possible under ideal conditions - for one component of a system. Plus its been noted that the upper high frequencies are unlikely to be something most of us can perceive to any significant degree anyway. If your hearing has been tested and proves otherwise then obviously that's a consideration for you.

Some context, the head unit is a NAD M10 V1 which is nCore powered and generally considered a good thing. I'm running an NAD sub from 120Hz. The M10 V1 measures midrange so far as its amplifier performance goes but sounds just fine as installed in my room with the sub. This unit has Dirac which when tuned properly elevates what comes out of the speakers. DSP is a whole different discussion but its very effective in this case.

I had been contemplating an Eigentacht update either NAD or VTV. The Fosi bench marks similarly at a fraction of the cost. The difference in sound clarity is noticeable. With Dirac on top its just great - for peanuts. The quibbles over whether it measures better or worse than others don't really matter to me. Its quite a bit better than what I had, job done and for not much money for even more win. And therein the lesson, everyone has different motive and priorities. Horses for courses.
 
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A more inaudible difference ... is inaudible anyway. Numbers are good to know if you're buying a decent level of engineering and (of course) a transparent amp

Up from that ... there's no better for your ears in a blind test. So, buying one amp because at 18khz have 1% less distortion ... don't work for me.

If 200 watts at 4 ohms is enough for you, I don't think you'll have "better sound" from other amp.
 
You'll be far better off selling them to someone like me who would like a pair
The Fosi were already so very cheap via Kickstarter, selling the Muses02s would make the purchase an even better deal that the great deal it already is I would feel like I have cheated the system
 
Hi,
I am really surprised to have to rise high volume (80% on my DAC smsl do300) to power my speaker with 2x V3 with psu 48v 5A in XLR ...

They have a low sensibility (86db) but i'm still really worried about putting so much power (AT least 100w) to feed them...

Class D reality ? DAC preamp not good enough ? Any opinion ?
 
Hi,
I am really surprised to have to rise high volume (80% on my DAC smsl do300) to power my speaker with 2x V3 with psu 48v 5A in XLR ...

They have a low sensibility (86db) but i'm still really worried about putting so much power (AT least 100w) to feed them...

Class D reality ? DAC preamp not good enough ? Any opinion ?
Same experience..... I have to crank up the volume to -30dB to -20dB of my Eversolo DAC-Z6 to play my chr120 & maop11 speakers loud. I even tried up to -15dB, the good thing is it is very silent even when I pause the music. And when it is playing , no audible distortion on music.

Not a technical guy but I think the gain of V3 mono is low. Am using the xlr input.
 
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No pops or anything when using smart plugs to turn them on? And what mode do you use in combination with smart plug, “on” or “auto”?
Test the behavior of the amplifier after being cut off.
V3 mono "On" mode: (be careful with playback volume)
When the power is cut off in "On" mode, in addition to the relay sound of the amplifier itself, there is obvious noise from the speaker.

V3 mono "Auto" mode (has entered Standby)
The V3 mono is first triggered to power on and then power off, making a small audible pop noise.

For comparison, here is the behavior of ZA3.
Power is cut off in "On" mode. the remaining power is slowly consumed within a few seconds.

Set the V3 mono to "Auto" mode and wait 10 minutes to enter Standby before using the Smart plug to turn off the power to avoid obvious noise from the speaker.
My personal opinion is that V3 mono is a step backward compared to ZA3 in this behavioral design.
 
Hi,
I am really surprised to have to rise high volume (80% on my DAC smsl do300) to power my speaker with 2x V3 with psu 48v 5A in XLR ...

They have a low sensibility (86db) but i'm still really worried about putting so much power (AT least 100w) to feed them...

Class D reality ? DAC preamp not good enough ? Any opinion ?
Just need a pre amp with some extra juice
 
Same experience..... I have to crank up the volume to -30dB to -20dB of my Eversolo DAC-Z6 to play my chr120 & maop11 speakers loud. I even tried up to -15dB, the good thing is it is very silent even when I pause the music. And when it is playing , no audible distortion on music.

Not a technical guy but I think the gain of V3 mono is low. Am using the xlr input.
Sorry what's the problem? Are you really unable to reach your listening volumes or do you simply need to turn the volume up a little more?
In the first case the solution is simple, you need a more powerful amplifier, in the second case there is no problem. In xlr the fosi has a gain of 25bd if I remember correctly, so your DAC can drive it at maximum power, if even at maximum this is not enough you simply need a more powerful amplifier
 
In xlr the fosi has a gain of 25bd if I remember correctly, so your DAC can drive it at maximum power, if even at maximum this is not enough you simply need a more powerful amplifier
20dB gain with XLR,25dB and 31dB with RCA.
 
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