Fosi Audio V3 Mono Amplifier Review

[yo!]

Hi there!

I have the V3 Fosi on my shortlist, stereo or mono type will all be OK for my usage.
The main reason is the auto on off function.

to make it short: Is the auto on off working reliable or are there pitfalls with this function? (Otherwise I go with another topping)

Greets!
yo

 

[vuittion]

There are no pitfalls that im aware of.

 

[EddNog]

Hi there!

I have the V3 Fosi on my shortlist, stereo or mono type will all be OK for my usage.
The main reason is the auto on off function.

to make it short: Is the auto on off working reliable or are there pitfalls with this function? (Otherwise I go with another topping)

Greets!
yo

Some of us (like myself) have had flawless performance from the auto-on/off feature, but I’ve also seen a number of people having noise on the mains cause the amps to turn/stay on (primarily people with light dimmers and/or LED bulbs, for some strange reason).

-Ed

 

[yo!]

Thanks for your feedback!
Oh ... this makes things not easier
Around 120 LEDs and a bunch of dimmed power supplies are installed here ... but this really sounds strange, maybe switching peaks in the power rails? IEM Filters ... ?

 

[Rafaille]

Thanks for your feedback!
Oh ... this makes things not easier
Around 120 LEDs and a bunch of dimmed power supplies are installed here ... but this really sounds strange, maybe switching peaks in the power rails? IEM Filters ... ?

If using balanced inputs you will most likely be fine. Only one person here has an issue with a floor standing lamp (on same socket electrical circuit as amps) but if I recall well, his preamp was picking up the noise that the LED was making, not the amp itself. As far as I can tell, all others that had issue with auto on/off were using unbalanced comnections.

 

[ninetylol]

I had strange pops while playing music with auto standy mode on. Wouldnt recommend counting on it working flawless.

 

[SMen]

Hi there!

I have the V3 Fosi on my shortlist, stereo or mono type will all be OK for my usage.
The main reason is the auto on off function.

to make it short: Is the auto on off working reliable or are there pitfalls with this function? (Otherwise I go with another topping)

Greets!
yo

I am using balanced inputs but I've got a couple of subwoofers connected to the pre-amp ... so switching on lights (since attaching these) can make the amps switch on.
But personally I don't mind the occasional 'click on' for whatever reason.

It is not as though I'm forever turning lights on and off.

More importantly, I think the mono's sound great. Most revealing 3255 amp I have had. First ever dual mono. I don't have experience of Toppings for comparison - I'll let those who do chip in on this (important) consideration (just a little edit if anyone noticed)

 

[EddNog]

I am using balanced inputs but I've got a couple of subwoofers connected to the pre-amp ... so switching on lights (since attaching these) can make the amps switch on.
But personally I don't mind the occasional 'click on' for whatever reason.

It is not as though I'm forever turning lights on and off.

More importantly, I think the mono's sound great. Most revealing 3255 amp I have had. First ever dual mono. I don't have experience of Toppings for comparison - I'll let those who do chip in on this (important) consideration (just a little edit if anyone noticed)

Re: Topping amps: different price class

-Ed

 

[yo!]

Nice, OK
I don't worry about sound quality this much. I still use a stack of not this good tested TP60 toppings, the system is DSP corrected and the sound is already pretty good for my listening levels that use to need 1-2 W, so I don't expect quantum leaps in quality (nor do I believe in it when I look at compression in audio sources even in 'high end' formats).
I really like to have a auto on/off cause it's too much trouble to switch'em on/off all the time. They too often run 24/7 behind closed rack doors.

Hm, balanced input is possible here, I guess I will give the fosi a try.

 

[SMen]

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.

 

[EddNog]

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

 

[amix]

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.

 

[DavidM1]

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.

 

[Melmoth]

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

 

[yo!]

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?).

 

[Melmoth]

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.

 

[burkm]

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...

 

[Zek]

because he pointed at the Elac Diamond 12.2

You mean Wharfedale.

 

[burkm]

You mean Wharfedale.

Corrected...

 

[musicforcities]

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.

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.