• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 7 1.5%
  • 2. Not terrible (postman panther)

    Votes: 11 2.3%
  • 3. Fine (happy panther)

    Votes: 95 19.8%
  • 4. Great (golfing panther)

    Votes: 368 76.5%

  • Total voters
    481

drmevo

Active Member
Joined
Feb 10, 2022
Messages
137
Likes
131
I bit on the Kickstarter earlier today, and got the 2 amp + 10A power supply bundle for 27% off. I’m curious if I’ll notice much difference vs. the Class D Pascal amp in my Parasound NewClassic 200 Integrated. I was kicking around the idea of getting a Hypex amp but this seemed to make sense for my set up and is certainly more budget-friendly.
Almost right on cue, my son was playing music this afternoon and the speaker outputs on the Parasound integrated cut out and won’t come back on. Wish this had happened a little closer to the delivery of the mono blocks, but at least I know I have a solution on the way if I can’t get this thing going again. Failing that, it’s back to my crummy Yamaha AVR for awhile.
 

iLoveCats

Active Member
Joined
Dec 8, 2019
Messages
274
Likes
325
Location
USA
Almost right on cue, my son was playing music this afternoon and the speaker outputs on the Parasound integrated cut out and won’t come back on. Wish this had happened a little closer to the delivery of the mono blocks, but at least I know I have a solution on the way if I can’t get this thing going again. Failing that, it’s back to my crummy Yamaha AVR for awhile.
'tis a blessing
 

lcheetec

Member
Joined
May 7, 2018
Messages
13
Likes
2
I've since backed it, for 2 + the single 10A, and very excited.

Already have two ZA3 and happy, but this one..... nice!
 

EddNog

Active Member
Joined
Mar 1, 2024
Messages
116
Likes
120
An informal survey of how many V3 Mono backers are upgrading from dual ZA3s would be quite interesting. There’s going to be a deluge of used ZA3s on the market in June!

-Ed
 

Fosi Audio

Senior Member
Audio Company
Forum Donor
Joined
Sep 10, 2021
Messages
327
Likes
1,616
@Fosi Audio, any plans to offer these as a bare amp board/module down the road?!
Sorry, we currently do not have a plan to offer amp boards or modules of the V3 mono in the short term, but we are indeed looking into this business.
 
  • Like
Reactions: gvl

36mbbj

New Member
Joined
Apr 21, 2024
Messages
3
Likes
9
@Fosi Audio:

Have you considered putting two of these amps into a single, 1U rack-mountable chassis?
One set of switches instead of two, most probably better cooling and if the PSU was in the same chassis, a MUCH tidier setup.

Such an amp could become the next Dynaco ST-70 or, if you want, the next NAD 3020 of power amps (yes, I'm that old).

P.S.: I've just checked your Kickstarter page for this product and I've noticed the "V3 Mono*2 + 48V/10A Power Supply*1" bundle, but I've not seen a proper description of it. I'm assuming there is some special cable to link both amp to the same PSU or are we dealing with a PSU that has two output connectors? Thanks for any explanation you can provide.

P.P.S.: I just needed to scroll further down the product's page to stumble onto the mention of a splitter cable that lets the 48V/10A PSU power two V3 Mono amps.
 
Last edited:

Fosi Audio

Senior Member
Audio Company
Forum Donor
Joined
Sep 10, 2021
Messages
327
Likes
1,616
Have you considered putting two of these amps into a single, 1U rack-mountable chassis?
One set of switches instead of two, most probably better cooling and if the PSU was in the same chassis, a MUCH tidier setup.
It feels like you're on the same wavelength as us! We've recently begun exploring a similar solution – housing multiple amplifier boards within a single chassis and incorporating an internal power supply. Users will have the option to install anywhere from 2 to 5 amplifier boards, somewhat akin to a NAS system supporting multiple hard drives.

I'm assuming there is some special cable to link both amp to the same PSU or are we dealing with a PSU that has two output connectors?
Yes, we'll provide a Y splitter cable for the connection. Probably we'll also provide an external power filter.
 

Cal_Cobra

Member
Joined
Mar 19, 2024
Messages
42
Likes
31
It feels like you're on the same wavelength as us! We've recently begun exploring a similar solution – housing multiple amplifier boards within a single chassis and incorporating an internal power supply. Users will have the option to install anywhere from 2 to 5 amplifier boards, somewhat akin to a NAS system supporting multiple hard drives.
Add BLUE back-lit VU meters and we have a winner ;)
 

Bleib

Major Contributor
Joined
May 13, 2021
Messages
1,395
Likes
2,481
Location
Sweden

He has some problems with the 48v / 10A powersupply. He recommends having 2 independent instead

Edit: I missed that he has posted a pinned comment, Fosi had already responded to this:
"Hi everyone, regarding my power supply issue, Fosi reached out to me with the following note: "We sent you a 48V/10A power supply along with a power splitter cable. However, as this is from the first batch of products, there is a noise issue when using the 48V/10A power supply with two units. We are currently working on solving this issue, and the officially sold products will not have this problem. Please be aware.""
 
Last edited:

Guddu

Addicted to Fun and Learning
Joined
Feb 10, 2020
Messages
953
Likes
859

He has some problems with the 48v / 10A powersupply. He recommends having 2 independent instead
Strange to think how may this be possible that they didn’t find it in their product before sending it to so called youtube influencers.
What happened to internal testing and all!
 

Bleib

Major Contributor
Joined
May 13, 2021
Messages
1,395
Likes
2,481
Location
Sweden
Strange to think how may this be possible that they didn’t find it in their product before sending it to so called youtube influencers.
What happened to internal testing and all!
I missed the pinned comment:
"Hi everyone, regarding my power supply issue, Fosi reached out to me with the following note: "We sent you a 48V/10A power supply along with a power splitter cable. However, as this is from the first batch of products, there is a noise issue when using the 48V/10A power supply with two units. We are currently working on solving this issue, and the officially sold products will not have this problem. Please be aware.""
 

LukeA

Member
Joined
Aug 25, 2022
Messages
7
Likes
3
It feels like you're on the same wavelength as us! We've recently begun exploring a similar solution – housing multiple amplifier boards within a single chassis and incorporating an internal power supply. Users will have the option to install anywhere from 2 to 5 amplifier boards, somewhat akin to a NAS system supporting multiple hard drives.


Yes, we'll provide a Y splitter cable for the connection. Probably we'll also provide an external power filter.
Do the y-splitter cables come with the 4x amp, 2x power supply backer option or do I have to add them as an extra?
 

Negatywny

Member
Joined
Jul 2, 2019
Messages
61
Likes
80
Location
warsaw
YT reviews jumped in line with the Kickstarter campaign. They are not particularly interesting, here you have this black box, it has this whimsical thing on the front, and it sounds very nice, subscribe ;) Well, I'm waiting for a review by Andrew Robinson, who has already recorded several rants for Chinese amplifiers, how they are almost a fraud because they have little power - you know, only 50W, and that's almost certainly not enough for everyone! But if you have to review a tube amplifier that has 10W and costs $10k, it can easily provide sound for a 70m2 living room ;) I wonder what this fool will say now.
 

amix

Member
Joined
Sep 20, 2020
Messages
76
Likes
44
We've recently begun exploring a similar solution – housing multiple amplifier boards within a single chassis and incorporating an internal power supply. Users will have the option to install anywhere from 2 to 5 amplifier boards, somewhat akin to a NAS system supporting multiple hard drives.
Very good!
 

antcollinet

Master Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
8,044
Likes
13,676
Location
UK/Cheshire
Strange to think how may this be possible that they didn’t find it in their product before sending it to so called youtube influencers.
When a device is pre production it is because the development is not finished. More often than not the product testing is still ongoing. It would be a surprise if pre production devices didn’t have some issues.
 

MCH

Major Contributor
Joined
Apr 10, 2021
Messages
2,714
Likes
2,352

He has some problems with the 48v / 10A powersupply. He recommends having 2 independent instead

Edit: I missed that he has posted a pinned comment, Fosi had already responded to this:
"Hi everyone, regarding my power supply issue, Fosi reached out to me with the following note: "We sent you a 48V/10A power supply along with a power splitter cable. However, as this is from the first batch of products, there is a noise issue when using the 48V/10A power supply with two units. We are currently working on solving this issue, and the officially sold products will not have this problem. Please be aware.""

Two out of two reviewers sharing power supply between two amps with a Y cable that have a noise issue. I hope it is not the below or they will have to come with some sort of active splitter. I will be curious to see what solution they come with, maybe some sort of filter to tame the PWM power demand spikes?

The power supply sharing is something interesting to me. Actually, various TPA3255 can be operated in master/slave mode so that they delay the switching between each other, apparently to "minimize noise coupling between audio channels through the power supply." and "Inter-channel delay is needed to optimize audio performance and to get better operating conditions for the power supply" according to the datasheet (below).
Given the fact that most probably two fosi sharing PSU with one of these Y cables are in fact directly connected in between, but not in master/slave mode, i would be curious to understand what this means for the performance of the amps and the power supply.

View attachment 361807

For full disclosure:

View attachment 363206
From here:

I don't see any mention to radio stations whatsoever, only to issues related to power supplies and noise. If you are referring to the choice of a different switching frequency to avoid radio interferences is a completely different thing.
 
Last edited:

Talisman

Major Contributor
Forum Donor
Joined
Mar 27, 2022
Messages
1,021
Likes
3,005
Location
Milano Italy
The problem is users who always have something to complain about.
When the za3 came out it was reviewed after a while and there was an avalanche of criticism for not sending the device first to have the review immediately upon release.
Then, to guarantee the review upon release, the company sends the devices still in the development phase (with inevitable problems of youth and parameters that are not yet perfectly definitive) and the same people complain about the review which does not represent the performance of the product launched on the market.
Make peace with your brain.
 
Top Bottom