Fosi Audio V3 Mono Amplifier Review

[Deleted member 72219]

From where is this information ? And why he should do this?

Approximately 9:50 or so into the video.

-Ed

 

[tomtoo]

I also think he ramped up the tests on a single V3 with the 48V 10A power supply

Why ramped up thats exactly what i would do.

 

[spandy]

Not sure why the vibe was off on his review, but it definitely was oddly dismissive. Class D dogma lives on I guess. Has anyone managed to change the Super Early Bird deal from 10a to 2*5a psus? Or are you all just paying the small increase difference?

 

[tomtoo]

Approximately 9:50 or so into the video.

View attachment 367358


-Ed

Hmm i have to watch again..

 

[bboris77]

View attachment 367354This is what Fosi sent to Erin. Its on the facebook group. It seems they are trying to find the root cause of the issue at least.

Their response makes me actually want to try one of their amps.

 

[Deleted member 72219]

Their response makes me actually want to try one of their amps.

Yes, exactly. That was a fantastic response on their part!

-Ed

 

[Jeromeof]

Why ramped up thats exactly what i would do.

Mostly the 48V 10A is for 2 V3 Monos - they have an option to buy 2 separate 48V 5A power supplies with each mono block or a splitter with the since 48V 10A. Looking at the version Amir tested it was a 48V 5A.

So, I am guessing the 10A on a single V3 Mono is reaching the limit of what it is capably off and then Erin tests obviously found some weak point in their design.

 

[Talisman]

View attachment 367354This is what Fosi sent to Erin. Its on the facebook group. It seems they are trying to find the root cause of the issue at least.

Have you understood @Eric Alexander how to react to a critical review in order to attract even more customers instead of making them run away?
#tekton

 

[tomtoo]

Mostly the 48V 10A is for 2 V3 Monos - they have an option to buy 2 separate 48V 5A power supplies with each mono block or a splitter with the since 48V 10A. Looking at the version Amir tested it was a 48V 5A.

So, I am guessing the 10A on a single V3 Mono is reaching the limit of what it is capably off and then Erin tests obviously found some weak point in their design.

Thats all possible and exactly why i like to have more information. There should never be a problem with a PS that can deliver more amps than needet. If it would be like that the amp has a serious proplem. "Weak" point?. Exactly so we have to investigate deeper. And for that more info is needet. From my point of view at least the video at this point is not satisfying. Wilston did a 2Ohm test i think only resistive and no proplem. So what was exactly different? Why the tpa did not switch off? Or was something else the weak part? A cap, a resistor, a induktor? Questions over questions at this point.

 

[ViperDom]

Looks like Erin from Erin’s Audio Corner has ascertained that there is, in fact, a measurable improvement using two separate 48V/5A power supplies rather than a single 48V/10A supply for two amps at once:

- Is this "measurable" difference audible?
- If he measured each 5A power supply individually would there also be a "measurable" difference based on the inherent tolerance?

- With individual PSU's is there greater chance of switching frequencies not syncing up?
- With 1 shared PSU are the amps more likely to be synced?

https://www.kickstarter.com/project...-mono-power-amplifier/faqs#project_faq_556615

Silly to see people switching their orders without knowing the answers to these questions...

 

[Rafaille]

Not sure why the vibe was off on his review, but it definitely was oddly dismissive. Class D dogma lives on I guess. Has anyone managed to change the Super Early Bird deal from 10a to 2*5a psus? Or are you all just paying the small increase difference?

Paying extra I am afraid is your sole option

 

[Deleted member 72219]

- Is this "measurable" difference audible?
- If he measured each 5A power supply individually would there also be a "measurable" difference based on the inherent tolerance?

- With individual PSU's is there greater chance of switching frequencies not syncing up?
- With 1 shared PSU are the amps more likely to be synced?

https://www.kickstarter.com/project...-mono-power-amplifier/faqs#project_faq_556615

Silly to see people switching their orders without knowing the answers to these questions...

¯\_(ツ)_/¯

I went with dual 5A PSUs from the get-go, so I am not one of the order-changers.

-Ed

 

[drmevo]

- Is this "measurable" difference audible?
- If he measured each 5A power supply individually would there also be a "measurable" difference based on the inherent tolerance?

- With individual PSU's is there greater chance of switching frequencies not syncing up?
- With 1 shared PSU are the amps more likely to be synced?

https://www.kickstarter.com/project...-mono-power-amplifier/faqs#project_faq_556615

Silly to see people switching their orders without knowing the answers to these questions...

It's not silly. For me, part of it is that I might lose interest and forget before this is all sorted out. These things won't be shipping for over a month, after all.

So far, I don't see any advantages to the 10A power supply other than only needing one outlet, and having the ability to add a second 10A down the line if desired. But needing two 10A PSUs right off the bat makes it less appealing to me. Any problems/inconsistencies so far have been with the 10A supply. If it gets fixed completely and I happen to notice, I don't see any reason I can't switch back. You keep you backer number, after all, so you don't lose your place in line for fulfillment.

 

[BossBunos]

What I noticed in erins review is the discrepancy in the bass response between his measurements and amir's. It's only a 0.25db difference at 10hz but in erins measurements it starts rolling off below 100hz where in amir's measurements it starts to roll off at 20hz...

 

[Fosi Audio]

@Fosi Audio Could you give us some more information regarding the power supply that would be on the 6.3 Ampere bench?

We apologize for the late response. Our team is currently investigating this matter. We will conduct a more comprehensive test on the power supply and also verify the situation with the manufacturer, Huntkey. We will post updates regarding this issue as soon as possible.

 

[amix]

@Fosi Audio 's silence these days and the new measurements have convinced me to change reward from single 48V 10(?)a to double 48v 5a

What's the price for these two supplies? I wonder whether two of the Siyima GaN 10A PSUs would be that much more expensive.

 

[amix]

This is what Fosi sent to Erin.

Good @Fosi Audio! Nice they want to investigate! Erin should have contacted them before making his video. Would also have been more interesting content,then.

 

[Trasam Audio]

@Fosi Audio 's silence these days and the new measurements have convinced me to change reward from single 48V 10(?)a to double 48v 5a

Too early, they are just on vacation. International Labour Day.

 

[SMen]

Erin talks a bit more about the fosi's in his latest review on the A07Max.

Where he is coming from is that he simply isn't hearing differences with or without PFFB.
I wonder what the ohms are of the speakers he is using are. I have 8ohm speakers so I will be curious to compare the fosi's with my other 3255 ... but I'll pop that on the user thread here in a few weeks time... https://www.audiosciencereview.com/...v3-mono-user-impressions-owners-thread.54043/

I hope I do hear after all the hype! ... but at least I suppose the reviewer Erin is deflating the hype.

 

[Descartes]

Thank Amir so much for the measurement! The V3 Mono is another amplifier co-created with members, following the V3 stereo amp. We would particularly like to thank @Toku, @ModDIY , @mike70 , @cyclo, and all the other members who have provided us with invaluable suggestions.

The V3 Mono is our first amp with PFFB implementation. During the period we sent the set to Amir for testing, our R&D team did not stop optimizing the V3 Mono, and we have now further improved its frequency response curve. Below is the chart for your reference.
View attachment 360736


The V3 Mono is currently in production, and it will be launched on Kickstarter on the 20th of this month. There will be very attractive discounts available then, and we hope you'll stay tuned!

Fantastic, are you working on a stereo one with the power block integrated?