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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 13 1.8%
  • 2. Not terrible (postman panther)

    Votes: 23 3.2%
  • 3. Fine (happy panther)

    Votes: 139 19.5%
  • 4. Great (golfing panther)

    Votes: 536 75.4%

  • Total voters
    711
Re: Topping amps: different price class

-Ed
Yes, but I've circumnavigated that with other gear before now, currently unexpectedly with my step-relay pre-amp. I think you might have too...
And those different price class toppings I saw you were using might just themselves bat above their price class ...

which of course makes this such fun.
 
Yes, but I've circumnavigated that with other gear before now, currently unexpectedly with my step-relay pre-amp. I think you might have too...
And those different price class toppings I saw you were using might just themselves bat above their price class ...

which of course makes this such fun.
Oh for sure, price class and performance class are entirely two different things.

Budget, however, is a singular thing.

-Ed
 
Is the auto on off working reliable or are there pitfalls with this function? (Otherwise I go with another topping)
Works flawlessly! Surprisingly well. You should be aware though, that some people, including me, experienced erratic triggers (ON) of the function when switching nearby lights. I solved it with an AC filter, that gets used in PA racks.
 
to make it short: Is the auto on off working reliable or are there pitfalls with this function? (Otherwise I go with another topping)
Works great and it’s a feature I use constantly.

You will likely hear the solenoid click as it turns off and on. I’ve had no instances of electrical circuits triggering a “switch on” however if I turn off the DAC after the amps have switched off earlier in the evening they will turn back on for 10min. I don’t consider this a problem.
 
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Hi, this is my first post here. I just bought a pair of ELACs UBR62 (6 ohms / 83 dB sensitivity) and was wondering if someone tried them with the V3 mono, do these deliver enough power to drive them?
In the technical specifications it is stated that the maximal amount of power they can handle (the UBR62s) is 140W
I'd be using them in a 20 sqm living room, guess mostly to listen at 75-80 db, maybe once in a while go up to 85-90 db
Thanks a lot in advance for any help :)
 
Hi, this is my first post here. I just bought a pair of ELACs UBR62 (6 ohms / 83 dB sensitivity) and was wondering if someone tried them with the V3 mono, do these deliver enough power to drive them?
In the technical specifications it is stated that the maximal amount of power they can handle (the UBR62s) is 140W
I'd be using them in a 20 sqm living room, guess mostly to listen at 75-80 db, maybe once in a while go up to 85-90 db
Thanks a lot in advance for any help :)
Ola!
With ease! You're fine with 0.5-10 W, and give it some headroom of 10 dB, it's just around 100 W peak in worst case (90-100 dB in 1 m distance), you might want more in regular distance of about 2.5 m, but then, calculated, it'll be another 10x of power to match 'real' 100 dB, but that's way beyound what your speakers can handle, and the difference between 140 W and let's say 300 W is not this much (3 dB?).
 
Ola!
With ease! You're fine with 0.5-10 W, and give it some headroom of 10 dB, it's just around 100 W peak in worst case (90-100 dB in 1 m distance), you might want more in regular distance of about 2.5 m, but then, calculated, it'll be another 10x of power to match 'real' 100 dB, but that's way beyound what your speakers can handle, and the difference between 140 W and let's say 300 W is not this much (3 dB?).
Thank you very much for your response.
 
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I read the whole review in Your link https://www.alpha-audio.net/review/review-wharfedale-diamond-12-2-bright-like-a-diamond-en/3/ (five pages)
I wondered somewhat about Your reply, because the mentioned Wharfedale Diamond 12.2 speaker in that review had those distortion problems with all mentioned (well known) amps listed (my fault (?) I didn't find the Fosi Audio V3 Mono not even mentioned), because, as concluded in the final section by the reviewer, he diagnosed the problem due the inductance value in that corresponding frequency divider branch of the speaker, which seemed to have a false value ...

I probably misinterpreted the former message of user "Freezak", because he pointed at the Wharfedale Diamond 12.2 and not on the Fosi Audio V3 Monos as I thought. Thus my comments were misleading...
Sorry about that...
 
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I know I'm gonna get a lot of hate for this. But here goes, these amps are great, no doubt and an excellent value. But what is the deal with external power supply? And what is the deal with that cute little miniature size form factor, is it meant to be a desktop amp?

Can't we just put two of these mono and their power supply into one case? Who started this silly trend? It screams dorm room HiFi component. :p
It’s not silly at all. Nor a trend. It is simple far more economical to use an external psu within the production and pricing format of these things. Putting the high voltage in a separate box means it can be certified and meet safety regulations more easily. It can be made by a fabricator that specializes in such bricks. And therefore can do it for a lower price point. Mains noise can be more easily isolated. Power supplies can be revised separately.

And do not underestimate the potential increase in manufacturing a larger metal case. Small cases can get away with thinner sheet metal, bends of correct tolerances are far easier. Smaller units are easier to tool and move on an assembly line. More units can be cut from a sheet of raw stock, likely with less waste. And packaging and potential damage in shipping is easier.

Power bricks are here to stay.

And there are potential benefits to the user. You can hide the brick someplace. You can keep your ac line voltage away from line level interconnects more easily. Etc.
 
I know I'm gonna get a lot of hate for this. But here goes, these amps are great, no doubt and an excellent value. But what is the deal with external power supply? And what is the deal with that cute little miniature size form factor, is it meant to be a desktop amp?

Can't we just put two of these mono and their power supply into one case? Who started this silly trend? It screams dorm room HiFi component. :p
That’s funny. When I see big hifi boxes these days it just looks like 1999.
 
It’s not silly at all. Nor a trend. It is simple far more economical to use an external psu within the production and pricing format of these things. Putting the high voltage in a separate box means it can be certified and meet safety regulations more easily. It can be made by a fabricator that specializes in such bricks. And therefore can do it for a lower price point. Mains noise can be more easily isolated. Power supplies can be revised separately.

And do not underestimate the potential increase in manufacturing a larger metal case. Small cases can get away with thinner sheet metal, bends of correct tolerances are far easier. Smaller units are easier to tool and move on an assembly line. More units can be cut from a sheet of raw stock, likely with less waste. And packaging and potential damage in shipping is easier.

Power bricks are here to stay.

And there are potential benefits to the user. You can hide the brick someplace. You can keep your ac line voltage away from line level interconnects more easily. Etc.
It is good to have choices. But while external power supplies have their advantages in terms of cost, safety, and ease of production, they can also give the impression of lower build quality and detract from the unified design that we're used to.

External power bricks, while economical from a manufacturing standpoint, often feel like a compromise on quality and aesthetics. Built-in power supplies can meet stringent safety standards, and with proper shielding, they can effectively manage noise without the need for external components that might introduce issues with long cables or placement. Integrated designs also ensure that power supplies are optimized for the specific amplifier design, avoiding the complications of revisions or compatibility issues when the brick dies and a replacement is needed. While smaller cases are easier and cheaper to manufacture, larger, solid enclosures add to the product's durability, performance, and overall appeal, which many audiophiles value. Additionally, managing an external brick creates clutter, detracting from the clean look of a well-organized audio setup, and gives the impression of cost-cutting rather than long-term durability or quality. And tossing it in with a tangle of other cables and other power bricks could lead to overheating issues.

Advantages, disadvantages, personal preferences, and differing opinions.. :) It is good to have choices.
 
Mine arrived. They are going to be returned for a refund.

I ordered 2 from the Fosi website with the single 48v 10amp PSU. No phase issue and they came with the filter for the splitter. The filter is labeled and was connected properly. They were on their own wall outlet and power/audio cables were separated. No dimmers or special bulbs here. They seemed to work well day one until I powered them off for the night. When I powered one down there was a very loud pop (some have mentioned they pop when powering off). And the other sent a buzz sound to the speaker. I powered the second one down and it also popped. I decided to try again in the morning.

In the morning I powered one on, it popped and it made the speaker buzz until I turned on the second one, which also popped. The buzzing went away. I decided to let them rest before sending music but after about 15 minutes of them powered on with no music they started sending distortion noise to both speakers. I did power cycle them a few times, the distortion was changing frequencies, and the buzz was always there when only one was powered on, but what got me was the pop. These were sending very loud pops to my speakers whenever they were power cycled. The pop was so loud I was worried they would damage my speakers or other components.

I tried using on vs. stand-by, multiple cables, sources, double checked connections, etc. Nothing worked. There was always distortion, buzzing, and loud pops. Maybe I got lemons? But with such a bad experience and worry about how they may damage my setup, I boxed them back up. I will be sending them back to Fosi as faulty and getting a full refund. I will not be trying them again in fear of damage to my equipment.

I'm very happy these have worked for so many, and I really wanted to love this product but I don't want to risk poor reliability and potential damage to my setup.

EDIT:
Primary chain was Tidal > Wiim Ultra > Fosi V3 Mono's > Magnepan 0.7s
I bought new cables to test and my volume is between 60 to 70 db. I certainly was not pushing these.

The funny thing I forgot to mention, mine never got hot. I expected them to get hot running maggies. They became warm but never too warm to touch or any hot temperature that made me think they may even need a fan. I don't know if that has anything to do with my experience?
 
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It is good to have choices. But while external power supplies have their advantages in terms of cost, safety, and ease of production, they can also give the impression of lower build quality and detract from the unified design that we're used to.

External power bricks, while economical from a manufacturing standpoint, often feel like a compromise on quality and aesthetics. Built-in power supplies can meet stringent safety standards, and with proper shielding, they can effectively manage noise without the need for external components that might introduce issues with long cables or placement. Integrated designs also ensure that power supplies are optimized for the specific amplifier design, avoiding the complications of revisions or compatibility issues when the brick dies and a replacement is needed. While smaller cases are easier and cheaper to manufacture, larger, solid enclosures add to the product's durability, performance, and overall appeal, which many audiophiles value. Additionally, managing an external brick creates clutter, detracting from the clean look of a well-organized audio setup, and gives the impression of cost-cutting rather than long-term durability or quality. And tossing it in with a tangle of other cables and other power bricks could lead to overheating issues.

Advantages, disadvantages, personal preferences, and differing opinions.. :) It is good to have choices.
Don’t tell the old school audiophile crowd…they love to pay extra for external power supplies. Naim and Quad, Cyrus, are a few brands that made a big selling point of external psu abd “upgrades” for such.

I have joked before that fosi should offer a sudiophile “ styling” option where they charge three times more for the same plastic power brick hot glued inside a metal case matching the house style of their components.


I’m just saying I suspect the external switching psu is integral to the models of fabrication, global distribution that makes devices with low price at high performance possible.

Thought of two more advantages:

switching supplies — especially lower priced ones —can be electrically noisy in terms of em fields, etc. and that may require extra shielding if in the same enclosure. I have had cheap power bricks introduce noise into rca /single ended inputs/outputs when placed right next to the jacks , for example.

second, given that switching power supplies are often more prone to failure than old linear supplies, external supplies have certain maintenance and repair advantages.

I used to detest power bricks too. I caved at some point…and would not go back. I throw them all in hidden cabinet or nice looking box with the power strip, using short ac cords. Much neater in the end and no more issues with mains noise being introduced into single ended signal paths. Or turntable signals.

Now, in a proper av rack for my centralized distribution, these things are a pain in rear. Then again so athe the main units and many other devices. I end up just mounting the psus on a rack shelf with zip ties and industrial Velcro, with the main units in the same or different shelf the same way.
 
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Just received a pair of these from Amazon and hooked them up to WiiM Pro Plus. Everything is completely out of sight except for the speakers.

Imma loving them!
 
Hello! Has someone purchased the sp601, are there any owners?
What is it? And what has it got to do with the V3 Mono?
 
What is it? And what has it got to do with the V3 Mono?
This has a direct bearing on V3 mono. I ordered 2x V3 mono for myself and I'm thinking of ordering Fosi sp601 for them. Fosi sp601, as you might guess, is acoustics. And since they were previously mentioned in this discussion thread, I decided to ask myself for this acoustics, perhaps someone has already purchased them for their v3 mono. I'm sorry that I didn't immediately write in detail what I mean :)
 
This has a direct bearing on V3 mono. I ordered 2x V3 mono for myself and I'm thinking of ordering Fosi sp601 for them. Fosi sp601, as you might guess, is acoustics. And since they were previously mentioned in this discussion thread, I decided to ask myself for this acoustics, perhaps someone has already purchased them for their v3 mono. I'm sorry that I didn't immediately write in detail what I mean :)
Acoustics.. you mean loudspeakers?
 
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