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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 12 1.9%
  • 2. Not terrible (postman panther)

    Votes: 19 3.0%
  • 3. Fine (happy panther)

    Votes: 121 19.4%
  • 4. Great (golfing panther)

    Votes: 472 75.6%

  • Total voters
    624
I think the fact that Fosi sells op amps demonstrates that they don’t mind selling product where there is a demand.

It has zero appeal to me.
And it does not even stay flat under the weight of 3 units
 
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update/edit : seems on of my speakers has a defect.

Screenshot 2024-10-01 110613.png
 
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So much problems with these V3 Monos. I just noticed one of mine distorts heavily in the 2-7k range. I even swapped the blocks with speakers, its one device introducing distortion like crazy (not the speaker or source). Im starting to hate these. 10% THD so audiophile these things lol.....

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Better stop further testing with it,you're near burning tweeters territory.
 
Sorry from new testing it actually seems its the speaker itself. It is pretty new and while changing the room i must have switched them with the blocks. I noticed, that first left then right had the distortion, but its not the V3M its the Wharfdale 12.2. You can also see its exactly where the crossover to tweeter should be.
 
Sorry from new testing it actually seems its the speaker itself. It is pretty new and while changing the room i must have switched them with the blocks. I noticed, that first left then right had the distortion, but its not the V3M its the Wharfdale 12.2. You can also see its exactly where the crossover to tweeter should be.
I remember reviews criticising this model for a very noticeable distortion in voice area.
 
Isolating the problem device is somtimes hard. If it would be really the Fosi Audio V3 Mono amp, You probably still got warranty for those. New units might sometimes fail early no matter what the price or quality control has been. Thus early failures might happen everywhere with everything. If You think, that the amps are responsible for the stated problems, let Fosi Audio know about it and have them serviced or exchanged the unit right away.

@Freezak
I have not read any reviews, and I read a lot, critizising, that in the voice region "very noticable distortion" was detected. Would You be so kind and provide the URLs for those reviews...
Defects may always happen, but shouldn't "accumulate" or be "ignored"...
 
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Isolating the problem device is somtimes hard. If it would be really the Fosi Audio V3 Mono amp, You probably still got warranty for those. New units might sometimes fail early no matter what the price or quality control has been. Thus early failures might happen everywhere with everything. If You think, that the amps are responsible, let Fosi Audio know about and have them serviced or exchanged right away.

@Freezak
I have not read any reviews, and I read a lot, critizising, that in the voice region "very noticable distortion" was detected. Would You be so kind and provide the URLs for those reviews...
Defects may always happen, but shouldn't "accumulate"...
This one v
"We can be fairly brief: the Wharfedale Diamond 12.2 doesn’t perform well in our measurements. The frequency response is pretty much okay, but where it goes wrong is distortion. We see a huge peak around 190 Hz (1.8%) and then another one around 560 Hz (3%). These are nasty, because the one at 560 Hz is at 3% and also full in the vocal range. Then another hump between 2000 and 3000 Hz. That one is just above 1%."
 
This one v
"We can be fairly brief: the Wharfedale Diamond 12.2 doesn’t perform well in our measurements. The frequency response is pretty much okay, but where it goes wrong is distortion. We see a huge peak around 190 Hz (1.8%) and then another one around 560 Hz (3%). These are nasty, because the one at 560 Hz is at 3% and also full in the vocal range. Then another hump between 2000 and 3000 Hz. That one is just above 1%."
1% is one thing up there,though 8-9% as we see above is totally different.
That's a graph of a deformed voice coil,either from pushing it in or from heat.

Or a x-over issue?
But not normal,at all.
 
1% is one thing up there,though 8-9% as we see above is totally different.
That's a graph of a deformed voice coil,either from pushing it in or from heat.

Or a x-over issue?
But not normal,at all.
Perhaps there's some QC problem with Diamond 12.2, hard to say, it could as well be the V3 Mono. It would be a good idea to try some other speakers paired with this unit and, perhaps, different V3 Mono too if needed.
 
Can anyone explain why 3rd hamonic though What does it mean shouldnt highest be 2nd? Its pretty obvious that its a tweeter or Crossover Problem though. It is audible too.

Perhaps there's some QC problem with Diamond 12.2, hard to say, it could as well be the V3 Mono. It would be a good idea to try some other speakers paired with this unit and, perhaps, different V3 Mono too if needed.
I also tried 12.1 and Lintons with the V3M and while one Linton speaker exhibited the same problem in similar area it was just above 1% THD. My two different pairs of 12.2 both had some distortion spikes at 500-600Hz (~1% THD@75db) too btw. So i think the review is not lieing. I also found another review which shows the same thing about the 12.2

Since i also have Linton measurements with the Wiim Amp and its similar with one speaker, i think the V3Mono are working as intended.
 
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This one v
"We can be fairly brief: the Wharfedale Diamond 12.2 doesn’t perform well in our measurements. The frequency response is pretty much okay, but where it goes wrong is distortion. We see a huge peak around 190 Hz (1.8%) and then another one around 560 Hz (3%). These are nasty, because the one at 560 Hz is at 3% and also full in the vocal range. Then another hump between 2000 and 3000 Hz. That one is just above 1%."
I read the whole review in Your link https://www.alpha-audio.net/review/review-wharfedale-diamond-12-2-bright-like-a-diamond-en/3/ (five pages)
I wondered somewhat about Your reply, because the mentioned Wharfedale Diamond 12.2 speaker in that review had those distortion problems with all mentioned (well known) amps listed (my fault (?) I didn't find the Fosi Audio V3 Mono not even mentioned), because, as concluded in the final section by the reviewer, he diagnosed the problem due the inductance value in that corresponding frequency divider branch of the speaker, which seemed to have a false value ...
 
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I wonder somewhat about Your reply, because the mentioned Wharfedale speaker in that review had those distortion problems with all connected (well known) amps (I didn't find the Fosi Audio V3 Mono not even mentioned), because, as concluded in the final section by the reviewer, he diagnosed the problem due the inductance value in that corresponding frequency divider branch of the speaker, which seemed to have a false value ...
Freezak was speaking about the Wharfedale 12.2 in particular (sorry for hijacking this thread)
 
Can anyone explain why 3rd hamonic though What does it mean shouldnt highest be 2nd? Its pretty obvious that its a tweeter or Crossover Problem though. It is audible too.


I also tried 12.1 and Lintons with the V3M and while one Linton speaker exhibited the same problem in similar area it was just above 1% THD. My two different pairs of 12.2 both had some distortion spikes at 500-600Hz (~1% THD@75db) too btw. So i think the review is not lieing. I also found another review which shows the same thing about the 12.2

Since i also have Linton measurements with the Wiim Amp and its similar with one speaker, i think the V3Mono are working as intended.
Yeah this sounds like a speaker problem then, bummer it was never reviewed by @amirm, but perhaps it's old enough right now that we might as well forget about it, it doesn't appear to be a good choice, unfortunately.
 
My situation with @Fosi Audio support is getting worst . After all this time, i receive a package today . But i ordered and pay/pledge two monos and they only send one!! This is unbelivable!!!! So with one mono i can´t do anything!!!!!!
 
You don't have to agree to my position and opinion :facepalm: :)

My opinion: It's not Fosi Audio's fault but that of the Spanish Customs. Thus I don't know what You are complaining about because Fosi Audio is going to sent another set to Your address. Fosi can't probably sent Your V3 monos because they don't have any available currently, thus Your official address and the trackin ID is placed on the waiting list. Nobody is going to conjure up because of this, You just have to wait, don't You, although patience doesn't seem to be Your primary motion ?

Sorry, neither I can't help You nor - at least it seems to me - Fosi Audio right away...»
Update , today i receive one mono only . @Fosi Audio doesn´t send two as i backed up on the kickstarter. So this is still good support for you? Worst experience i have ever had.
 

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