Fosi Audio V3 Mono Amplifier Review

[AdamG]

Got it. Thanks, all. Very helpful. Perhaps I'll still get these and build a second system!

Welcome Aboard @ppdl3 !

 

[druskys]

I’ve been reading a lot (focused mostly on trying to figure out Sinad/distortion/etc.) and feel like I’ve gotten nowhere… so, I’m just going to accept I need to ask and see if someone here can explain.

I’m strongly considering the wiim ultra (over 120 sinad per company specs) paired with the Fosi monoblocks (over 100 sinad with xlr but mid 90s with rca).

1. If RCA is used (wiim doesn’t have xlr), SINAD is such that the amp is no longer in the excellent category, right?
2. In general, what is the point of having a DAC with 120+ SINAD score if amps reviewed here aren’t getting that high? Seems like you’ll always be at the mercy of the amp sinad?
3. If I use the wiim ultra, am I losing that sought after SINAD score as soon as it hits the Fosi monoblocks via rca?

I realize after reading that sinad is more complicated than just a number and actually takes into account a couple of things. That being said, I was really excited for the above pairing until I realized how far different the SINAD scores were. Seems like I should just wait for the wiim amp pro to come out (claiming 120 SINAD).

Also, sorry for the novice questions. I’ve been trying to do my due diligence, but am not getting good answers. Thanks!

 

[Sokel]

I’ve been reading a lot (focused mostly on trying to figure out Sinad/distortion/etc.) and feel like I’ve gotten nowhere… so, I’m just going to accept I need to ask and see if someone here can explain.

I’m strongly considering the wiim ultra (over 120 sinad per company specs) paired with the Fosi monoblocks (over 100 sinad with xlr but mid 90s with rca).

1. If RCA is used (wiim doesn’t have xlr), SINAD is such that the amp is no longer in the excellent category, right?
2. In general, what is the point of having a DAC with 120+ SINAD score if amps reviewed here aren’t getting that high? Seems like you’ll always be at the mercy of the amp sinad?
3. If I use the wiim ultra, am I losing that sought after SINAD score as soon as it hits the Fosi monoblocks via rca?

I realize after reading that sinad is more complicated than just a number and actually takes into account a couple of things. That being said, I was really excited for the above pairing until I realized how far different the SINAD scores were. Seems like I should just wait for the wiim amp pro to come out (claiming 120 SINAD).

Also, sorry for the novice questions. I’ve been trying to do my due diligence, but am not getting good answers. Thanks!

I'll puzzle you a little more by pointing out that if the SINAD is your aim the numbers you read are usually for the full output of the DACs and for a specific frequency (that's for all).
I would urge you to study the Power vs Distortion charts (all of them,for amps) and the IMD vs level and THD+N Ratio vs Frequency for DACs,for starters.

 

[druskys]

I'll puzzle you a little more by pointing out that if the SINAD is your aim the numbers you read are usually for the full output of the DACs and for a specific frequency (that's for all).
I would urge you to study the Power vs Distortion charts (all of them,for amps) and the IMD vs level and THD+N Ratio vs Frequency for DACs,for starters.

Haha thanks. I watched Amir’s videos yesterday on the subjects and have been doing some reading. There’s probably a reason I didn’t become an engineer

Most important to me: will it be completely out of the audible range whether or not I use rca or xlr with the Fosi? In that case, I don’t care and will go for that setup as it is easy/cheaper than other options I’m considering…

If it matters, my setup is a pair of bmr monitors from philharmonic audio and a rhythmic l12 sub.

 

[rvsixer]

What would be the benefit of two 48v 10a over two 48v 5a power supplies?

According to Fosi: The following possible advantages (see first FAQ entry):

https://www.kickstarter.com/projects/fosiaudio/fosi-audio-v3-mono-power-amplifier/faqs

 

[antcollinet]

Most important to me: will it be completely out of the audible range whether or not I use rca or xlr with the Fosi? In that case, I don’t care and will go for that setup as it is easy/cheaper than other options I’m considering…

Yes - with one proviso. The main point of XLR is noise immunity - particularly ground loop noise (a system, not a component problem, related to how all the components are grounded and interconnected)

As long as you don't have a noise problem, then yes, the difference will be out of the audible range.

 

[Kimbrough Xu]

Any idea what the longevity of the Fosi Audio V3 Mono amp should be compared to Hypex or Purifi amps? I have always stayed away from external power supplies in the past as they typically have been the weakest link in my experience.

They have 24 months warranty, so the longevity can be at least 24 months.

 

[Guddu]

They have 24 months warranty, so the longevity can be at least 24 months.

Wondering how the warranty term works - sending unit back to where?
China?

 

[iLoveCats]

Guys, this is throw away stuff. I know that irritates many people. I've been apart of the PA5 debacle with 3 units and Topping didn't miss a beat. Keep on producing and minimize the problems. These companies seem to have found the market is resilient to possible reliability problems as long as top performance, cheap gear gets released quickly. I'm ok with it. I was really upset when I had $2500 worth of broken NAD gear. I was only annoyed with a $350 Topping amp. I won't blink an eye is a Fosi V3 mono takes a dump and I'll buy the next equivalent thing.

 

[Snoopy]

Guys, this is throw away stuff. I know that irritates many people. I've been apart of the PA5 debacle with 3 units and Topping didn't miss a beat. Keep on producing and minimize the problems. These companies seem to have found the market is resilient to possible reliability problems as long as top performance, cheap gear gets released quickly. I'm ok with it. I was really upset when I had $2500 worth of broken NAD gear. I was only annoyed with a $350 Topping amp. I won't blink an eye is a Fosi V3 mono takes a dump and I'll buy the next equivalent thing.

Yeah let’s keep adding stuff to the landfills with more and more throwaway stuff.

 

[somebodyelse]

Wondering how the warranty term works - sending unit back to where?
China?

Depends where you bought it. If you buy from Audiophonics you send it to France.

 

[Paffi]

Seeing this brings the idea of selling my Apollon Purifi 1ET400 and buy a bunch of these instead into my head

 

[Paffi]

That would be a trade from quality to trash. Downgrade in performance and longevity not to mention the Purifi runs much cooler.

So you assume it would be an audible difference? For the price of the Purif you could by 10+ Fosis

 

[staticV3]

So you assume it would be an audible difference? For the price of the Purif you could by 10+ Fosis

The difference in noise and output power may be audible, depending on your speakers' efficiency and listening distance.

The rest, probably inaudible.

 

[Talisman]

So you assume it would be an audible difference? For the price of the Purif you could by 10+ Fosis

The purifi is a state of the art amplifier, with excellent performance in every area, however I doubt you will hear any difference other than power. The noise levels are also low enough to avoid problems even with high efficiency speakers in my opinion.
Clearly I wouldn't replace a purifi with a pair of V3 monos if I already had the purifi. But for those with a more limited budget or for a secondary system, Fosi monoblocks almost certainly provide transparent performance and it doesn't seem fair to me to call them "rubbish" or "landfill stuff" because up to now Fosi products have shown solid construction and There were no noticeable complaints about failures or problems.

 

[serak]

Hello everyone,
I plan to purchase these monoblocks as a replacement for my oldschool AV-Receiver onkyo TX-SR700 (from 2002 at original price around 800$). I'm currently running it (in stereo mode) as a temporary replacement for my original power amp (same price range and even slightly older than the onkyo), which has definitely gone to silicon heaven.

Based on the parameters and amirm measurements, it should be a significant improvement for me. Unfortunately, I don't have personal experience with any D-Class amplifier yet. Is there a chance that even with these "cheap" boxes I will really move up in sound quality?

 

[Doodski]

Based on the parameters and amirm measurements, it should be a significant improvement for me. Unfortunately, I don't have personal experience with any D-Class amplifier yet. Is there a chance that even with these "cheap" boxes I will really move up in sound quality?

You might hear a tiny difference but it in reality it is unlikely. Your Onkyo outputs a decent amount of power but it is not as 2 Ohm stable as the Fosi so you might hear something there but the differences might exceed your ears sensitivity.

 

[staticV3]

Is there a chance that even with these "cheap" boxes I will really move up in sound quality?

Unless you have an actual issue with your current Amp, like strong hissing noise, obvious clipping at higher volumes, or an audibly skewed response, no new Amp is likely to move you up in sound quality.

$200 or $2000, Class D or Class A, doesn't matter.

The biggest improvements always come from buying new speakers, improving room acoustics, or adding DSP.
DACs and Amps are secondary.

 

[Lednek]

Hello everyone,
I plan to purchase these monoblocks as a replacement for my oldschool AV-Receiver onkyo TX-SR700 (from 2002 at original price around 800$). I'm currently running it (in stereo mode) as a temporary replacement for my original power amp (same price range and even slightly older than the onkyo), which has definitely gone to silicon heaven.

Based on the parameters and amirm measurements, it should be a significant improvement for me. Unfortunately, I don't have personal experience with any D-Class amplifier yet. Is there a chance that even with these "cheap" boxes I will really move up in sound quality?

I think so! I am currently using a $200 SMSL AO200 for my 2 channel setup. If I remember correctly it rated at an honest 7owpc into 8 ohms. It sounds significantly better than my $1200 Dennon avr 3400x with a fluffed 100wpc channel rating. That being said, the fosi measures much better, with much more power.

 

[Sokel]

Hello everyone,
I plan to purchase these monoblocks as a replacement for my oldschool AV-Receiver onkyo TX-SR700 (from 2002 at original price around 800$). I'm currently running it (in stereo mode) as a temporary replacement for my original power amp (same price range and even slightly older than the onkyo), which has definitely gone to silicon heaven.

Based on the parameters and amirm measurements, it should be a significant improvement for me. Unfortunately, I don't have personal experience with any D-Class amplifier yet. Is there a chance that even with these "cheap" boxes I will really move up in sound quality?

I would care more about the protections involved than anything else.
What happens if they decide to let the smoke out?What happens with hard clipping,or DC events,etc.
Cause nice speakers going off is a hard pill to swallow,amps is the immediate link to them.