Fosi Audio V3 Mono Amplifier Review

[burkm]

I'm just being objective.

Are You ???

 

[Basilderat]

Interesting that Archimago measures single-tone distortion when using RCA input as 13dB worse (80dB vs 93 dB) than Amir's measurement.

Part II: Fosi Audio V3 Mono Amp; Class D + PFFB, TI TPA3255 - Retail box with single 48V/10A power supply and filter. [Power, Distortion, and Subjective Impressions.] And on rejoicing over "Solved Problems" in audio.

A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.

archimago.blogspot.com

I wonder if it's because he is using the 10A PSU? He picks up 10-15dB of 60Hz mains hum whereas Amir did not.

 

[Sokel]

Interesting that Archimago measures single-tone distortion when using RCA input as 13dB worse (80dB vs 93 dB) than Amir's measurement.

Part II: Fosi Audio V3 Mono Amp; Class D + PFFB, TI TPA3255 - Retail box with single 48V/10A power supply and filter. [Power, Distortion, and Subjective Impressions.] And on rejoicing over "Solved Problems" in audio.

A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.

archimago.blogspot.com

I wonder if it's because he is using the 10A PSU? He picks up 10-15dB of 60Hz mains hum whereas Amir did not.

It's because his measurements are at 1W and not 5W as Amir's plus whatever sample-to-sample variation may be and gain penalty.
You can see the penalty in XLR input here:

At 5W is 100dB SINAD and at 1W is near 95dB SINAD.

 

[antcollinet]

It's because his measurements are at 1W and not 5W as Amir's plus whatever sample-to-sample variation may be and gain penalty.
You can see the penalty in XLR input here:

View attachment 389910

At 5W is 100dB SINAD and at 1W is near 95dB SINAD.

Plus, Amir puts a lot of effort into the cleanliness of the setup to avoid introducing mains hum.

 

[Sokel]

Plus, Amir puts a lot of effort into the cleanliness of the setup to avoid introducing mains hum.

That's true but in this case (Arch's RCA input) noise competes with distortion at equal amounts.
It wouldn't have a better result even if one of two was way lower.

 

[ninetylol]

That's true but in this case (Arch's RCA input) noise competes with distortion at equal amounts.
It wouldn't have a better result even if one of two was way lower.

Golden sample? I dont think we can critizize archimagos results, He knows what hes doing.

 

[Sokel]

Golden sample? I dont think we can critizize archimagos results, He knows what hes doing.

No,no golden sample as Arch's XLR results are perfectly in check with Amir's.
More like a closer to real life result (well,that can be way worst than the lab conditions) .

And as a matter of fact,80dB SINAD is not bad at all,we're just spoiled here on ASR.

 

[saberger0357]

So is Amazon still shipping the reverse polarity versions?

 

[DCinATX]

So is Amazon still shipping the reverse polarity versions?

Definitely as of last week

 

[saberger0357]

Definitely as of last week

And is opening the up the only way to know for sure if they're reversed or not?

 

[DCinATX]

a couple other options:

1. Count the QA stickers on the back. In theory, one sticker = reversed polarity; two stickers = problem fixed at the factory.

2. Use a subwoofer “polarity” setting (if you have one) to listen for wave cancellation. It’s pretty noticeable.

 

[JLB321GO]

And is opening the up the only way to know for sure if they're reversed or not?

You can also use a test track, and hear the results.

 

[galego100]

Everybody talk about good customer experience of @Fosi Audio , mine is one of the worst i had. After almost 3 months , i have no monos( stuck in Spanish customs) , money is gone, i was a pledger, and @Fosi Audio doesn´t provide a solution. What a scam.

 

[ninetylol]

Everybody talk about good customer experience of @Fosi Audio , mine is one of the worst i had. After almost 3 months , i have no monos( stuck in Spanish customs) , money is gone, i was a pledger, and @Fosi Audio doesn´t provide a solution. What a scam.

I just posted in another thread, I have terrible experience with @Fosi Audio support too. I can only advise anyone not ordering from them directly, support wont help, dont honor their own return policies and act against european laws. Besides my support guy is insulting my will to return item. I think i never had such a terrible experience with support.

Dont order from Fosi directly!

 

[JLB321GO]

Dont order from Fosi directly!

That's my experience also. Order from Amazon, and return it if you're not happy. No questions asked.

 

[Fosi Audio]

Everybody talk about good customer experience of @Fosi Audio , mine is one of the worst i had. After almost 3 months , i have no monos( stuck in Spanish customs) , money is gone, i was a pledger, and @Fosi Audio doesn´t provide a solution. What a scam.

Sorry for the bad experience. Let me help you resolve it.

 

[Bernard23]

So is Amazon still shipping the reverse polarity versions?

The ones I received last week from amazon UK were the correct polarity.

 

[burkm]

How many QC stickers are at the bottom ?
Different Amazon.xx may have old and new deliveries, which could be of different status.

 

[Bernard23]

How many QC stickers are at the bottom ?
Different Amazon.xx may have old and new deliveries, which could be of different status.

Afraid I can't recall, I don't have the amps as I returned them

 

[Mort]

Are there any good reasons to put a DAC in between a Wiim Ultra and a pair of Fosi V3 monoblocks? I have an extra DL200, for instance.