Fosi Audio V3 Mono Amplifier Review

[Bleib]

With mono block amps using dedicated power supplies there will be zero crosstalk from the amps.

Yes. The main interesting thing is the power level of each amp. Do they stay very close to spec?

 

[Doodski]

Yes. The main interesting thing is the power level of each amp. Do they stay very close to spec?

Interesting question. The gain(s) of each amp should be very close I think. Perhaps somebody else can chime in and confirm that or give more information.

 

[Guddu]

What is O-NOORUS D1?

O-Noorus D1 - TPA3255 PFFB Stereo Amplifier - Front Display, Tone Control (with bypass) and Remote

Dear FMs, O-Noorus are working towards finishing their TPA3255 PFFB Stereo Amplifier "D1", I am sharing here some early information got so far and would add up more as and when I get any. Input：RCA Output: - PRE OUT（Sync with volume) - Subwoofer（Sync with volume) - Speaker Output -...

audiosciencereview.com

 

[Guddu]

Interesting question. The gain(s) of each amp should be very close I think. Perhaps somebody else can chime in and confirm that or give more information.

It should stay same or close to what's found in measurements/testing here if fed with same separate PSUs.

 

[Doodski]

27% increase in price, 36% increase in power at 4ohms. Hardly a monoblock premium here.

I'm not sure what you are meaning with that comment.

Ncx500 as mentioned is 45% increase in price and no increase in power.

Power specs in this case are not the end all and be all but the Fosi certainly does look attractive. The NCX500 has benefits that are about low Z, high current and high temp drive capability for longer duration time periods etc. We will see after these babies are torture tested how they stand up. Otherwise I think the Fosi V3 is a amazing piece.

 

[PlasticDoc]

The PFFB technology used by Fosi has been around for a long time. However, due to patents, this technology could only be used by certain manufacturers. Therefore, even TI, which developed the TPA3255 chip, was not allowed to provide technology using PFFB.
However, that patent expired about three years ago(?), and anyone can now use PFFB.

Could you, please, elaborate on this?

 

[Guddu]

Fosi certainly does look attractive. The NCX500 has benefits that are about low Z, high current and high temp drive capability for longer duration time periods etc. We will see after these babies are torture tested how they stand up. Otherwise I think the Fosi V3 is a amazing piece.

Fosi v3 mono indeed look attractive, Fosi have done amazing job with case work.
Comparing it with NCX500 isn't fare at all, but it does hold its own value strongly.

 

[Doodski]

stack them using the single 48v PSU. No difference from a 2xTPA3255 with a single PSU

There will be increased crosstalk and low Z drive will suffer from channel to channel as peak current requirements occur.

 

[Doodski]

Fosi v3 mono indeed look attractive, Fosi have done amazing job with case work.
Comparing it with NCX500 isn't fare at all, but it does hold its own value strongly.

It a sweet looking amp for sure. I agree the NCX500 is altogether different amp and comparing it was a far reach.

 

[JW001]

The products we talk about are often desktop models.

Is it because of their size they are desktop models??
Unless your office is very small, IMHO you can get better results placing your speakers on stands and equalizing for your chair as a listening position. I tried both setups.

 

[Power Pop 23]

This is a power amplifier which means they usually don't have volume controls. You need a preamp in front of it or a DAC with volume control.

Thank you @Fosi Audio for expanding your range of products with a power amplifier. Consider offering a power amplifier that can drive two or more channels.

 

[CT Man]

I'm a bit confused: is auto on/off 12v trigger or signal sensing? I can't tell from the picture if there's a 3.5mm input on the back. Screenshot from Fosi web site below looks like it's signal sensing. They only mention auto off, not auto on. They should clarify that.

​

 

[Yorkshire Mouth]

Fosi monoblocks - $280
Aiyima stereo - $220

27% increase in price, 36% increase in power at 4ohms. Hardly a monoblock premium here. The reviews also show monoblocks doing better at difficult loads.

Ncx500 as mentioned is 45% increase in price and no increase in power.

I’m not saying you’re wrong, but for many people (certainly not everyone, but to a large number) they’ll read $220 vs $280 as $200 and something vs $200 and something.

If you’re stepping up from the PA5 II Plus to the PA7 Plus, or LA90, then you check your bank balance and have a think. But between €200 and $299 there won’t be too many people who can comfortably afford one but can’t stretch to the other.

I know we’d all like everything to be as cheap as possible, but as Amir often notes, this is a couple of fast food meals.

 

[Doodski]

I'm comparing the decision to go for monoblocks: with Ncx500 you pay 45% more and get no power increase while with TPA3255 you actually get more watts per dollar.

I already explained the very basic differences that are large when the NCX500 amp is in actual operation. Do you understand what the NCX500 and other class D Hypex and Purifi amps are about?

EDIT: I apologize to the MODs for all this newbie chatter about NCX500 stuff.

 

[Yorkshire Mouth]

Is it because of their size they are desktop models??
Unless your office is very small, IMHO you can get better results placing your speakers on stands and equalizing for your chair as a listening position. I tried both setups.

I do have my speakers on stands.

I’ve posted about the rise of the desktop system elsewhere, but I think we need to stop viewing it as being a huge downward compromise from a pair of large floor standers in a lounge, because I think some of the very best listening can be done at a desk.

 

[nagster]

With mono block amps using dedicated power supplies there will be zero crosstalk from the amps.

My prediction is also around -120dB (measurement limit value), but I wanted to check it at least once just to be sure. I think it's my chronic illness.

 

[Doodski]

I think it's my chronic illness.

LoL.. I have a couple of those too... gg*

 

[daniboun]

What is O-NOORUS D1?

This is the next amp from this manufacturer )
D1 will be release soon but not on the site yet :

O-NOORUS D3 TPA3255 Stereo Power Amplifier 300Wx2 with Bluetooth USB O

Description: O-NOORUS D3 is a Bluetooth 5.0 audio amplifier for passive speakers that features a stereo 300 watt x2 power output. D3 is a 2.1 channel power DAC amplifier which is equipped with Bluetooth, USB, coaxial, optical, and 3.5mm aux input. Volume/input/treble/bass/color/brightness are...

www.o-noorus.com

 

[Fleuch]

Thanks! Just filled out the early bird discount form!

Lucky dude!

Looks like the early bird discount form has disappeared from the link given by Fosi.

Does this mean the current production run is (1) already oversubscribed based on early bird responses; (2) there will be no Kickstarter options; (3) going by the ZA3 pre-order history there will be a looo . . . . . ng wait for the next batch to become available ???

 

[Hipster Doofus]

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!

Discounts are nice can mine be blue please