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Fosi v3 Mono - User Impressions | Owner's Thread

My units have arrived and I’ve come immediately to inform other buyers/owners that the units do not come with thermal interface material between the heatsink and enclosure from the factory:

View attachment 377143

-Ed
I purchased two USB cooling fans from Amazon yesterday, one to sit underneath each amp (like I saw someone do in the review thread), the fans have already arrived. I don't want to take chances until a lot of these monos have safely run at operating temperature for a while. I still await my amps., no word yet......
 
This tuber mentioned it in 10:35 , when he compared V3 mono to PA7 Plus.
IIWI is one of YouTubes most articulate and entertaining subjective reviewers, but he is not an audio engineer or cognitive scientist.

It is obvious from the photo that the V3's are too close together to develop the wide soundstage that expectation bias attributes to monoblocks.
If he moves them apart, preferably just outside each speaker, and uses phase correct XLR cables, the soundstage will dramatically broaden. They can then be moved closer together if the expected soundstage is too wide bordering on holographic.

The cognitive bias of wide soundstage is one of the core benefits of mono amps, and a key reason we buy them. o_O
 
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I purchased two USB cooling fans from Amazon yesterday, one to sit underneath each amp (like I saw someone do in the review thread), the fans have already arrived. I don't want to take chances until a lot of these monos have safely run at operating temperature for a while. I still await my amps., no word yet......
Probably minor to a properly cooled device but that's what a fan randomly thrown on a audio device can do:


Of course it depends but only measuring can show it (unless it's severe enough to be audible) .
 
Tubers mentioned the Mono V3 is lack behind Topping PA7 Plus in the way of soundstage and details?? Your thought please?? the design of PA7 Plus doesn't attract me at all.
The question is the youtuber change the opamps in V3 mono? Post the video here.
 
IIWI is one of YouTubes most articulate purely subjective reviewers, but he is not an audio engineer.

It is obvious from the photo that the V3's are too close together to develop the wide soundstage that expectation bias attributes to monoblocks.
If he moves them apart, preferably just outside each speaker, and uses phase corrected XLR cables, the soundstage will widen as expected. o_O
I got what you mean .. ! I also disagree with him (IIWI) since he compared a stereo amp to mono V3. I can lend a PA7 plus from friend but I don’t have mono V3 to compare !
 
Probably minor to a properly cooled device
I'm hoping these amps are engineered to dissipate heat without needing the fans, but at $12 each it's worth trying. Hopefully the fans will be relegated to the "I might have something to fix that" box after a few weeks of testing. After this wait I'd hate to have to decide on a new product to replace them because of temperature issues.
 
The question is the youtuber change the opamps in V3 mono? Post the video here.
Don’t have to .. he did not change anything from PA7 plus either ! If you put sparkos or burson in there .. the prices all together will higher than PA7 plus
 
I purchased two USB cooling fans from Amazon yesterday, one to sit underneath each amp (like I saw someone do in the review thread), the fans have already arrived. I don't want to take chances until a lot of these monos have safely run at operating temperature for a while. I still await my amps., no word yet......
I ordered a pair of the 80mm ones and also one of the 140mm ones to put under my Freya+!

-Ed
 
Hopefully fans aren’t needed to maximize the lifespan of these amps. I’m not willing to go that route, personally, adding more gadgets and cords to my already somewhat cluttered system. If the amps fail prematurely then I trust they’ll get replaced.

Also starting to get just a hint of impatience. Not a knock on Fosi or complaining at all, just good old fashioned consumerism at play, I suppose.
 
Also starting to get just a hint of impatience
I find myself checking my email way more than usual, I should probably learn a lesson from this whole situation. I should be a little more satisfied with what I do have and enjoy that now. It's already better than I've ever owned. :)
 
You cannot say my McIntosh amplifier produce same sound level to your Fosi V3 mono ! :facepalm: Or your Fosi sounds the same with ayima A07
No, here they tend to let the measurements/testing speak for themselves.
 
Got my email today regarding power filter. Requested send amps and power bricks. Ordered 2 mono’s and 2 10amp bricks. I was backer 1000 something. US resident. Keeping fingers crossed. Hopefully will see in July.
 
Don’t have to .. he did not change anything from PA7 plus either ! If you put sparkos or burson in there .. the prices all together will higher than PA7 plus
PA7 Plus is more than 500.00, I bought 2 sparkos ss3602 on black Friday 68.00 each so 140 + 230 = 370.00, if you do Muses02 which you can find 4 for 40.00 total 270.00.
I sow the video he said slightly better than PA7, and never change the opamps.
 
My pair of V3 Mono’s arrived today, just wondering is it expected that these amps run so hot it is not possible to hold your fingers on the top of the case? Only my little V3 use to run just warm with its 48v power supply. Also, even with the gain switch at 25db I can barely move the volume knob of my P3 preamp any distance at all before the volume is too loud. I’m having to use digital volume control as well to tame things down a bit!
 
PA7 Plus is more than 500.00, I bought 2 sparkos ss3602 on black Friday 68.00 each so 140 + 230 = 370.00, if you do Muses02 which you can find 4 for 40.00 total 270.00.
I sow the video he said slightly better than PA7, and never change the opamps.
Sparkos 79.80$ ea US not including shipping (I'm not from US but AU) we don't have many Black Fri ! .. ! at least (4) 320-350$ US ->~ 550$ AUD for op-amp, both V3 I can get to my place from Kickstater around AUD 550$ as well ! in total it would costs around 1100$ AUD .. >>>> Topping PA7 Plus is just around 825$ AUD to my door from Shenzhen. I dont really mind just few hundrew dollars different but a sound quality different ! Also at 1100$ I have another range of option .. eg Eversolo F2 (1045$ AUD)?

I am not sure which video you are mention about but in the clip I posted. He seems prefered Topping over Fosi (from 10:35)
"slightly cleaner and offers slightly darker and deeper background , slightly wider soundstage with PA7 Plus". no doub Fosi provides a slightly warm sounding while Topping provides tighter bass and cleaner. Probably his subjective sound judgement base on his system.

Anyway, this is just what he said, I don't really mind his "slightly matter" !! It is really up to us for our own system !! I just wanna find a cheap replacement amp for my Sun room, setup. I will let both of my Sabaj a20a mono retire and rest in peace.
 
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Will the Fosi V3 Mono be profitable and practical enough that Fosi will eventually make them a standard product sold on their website rather than via kickstarter? I get the impression that those who have received the product are pleased with it.
 
Will the Fosi V3 Mono be profitable and practical enough that Fosi will eventually make them a standard product sold on their website rather than via kickstarter? I get the impression that those who have received the product are pleased with it.
Distribution is already set up in Europe through Audiophonics for example, so it seems yes.
 
The gain with the balanced input of V3 Mono is dramatically lower than gain at maximum volume/minimum attenuation on ZA3’s balanced input, regardless whether ZA3 is set to stereo or mono. I run a subwoofer (SVS SB-3000) that is separately fed from a preamp simultaneously with the power amps, and I had to turn the subwoofer’s volume setting down ~15db in the DSP control app to level match after swapping amps.

-Ed
I'm using the ZA3 in mono mode the drive my center channel and I can confirm, with the amp set to max gain, it is +7dB higher than the internal amps on my AVR. That said, it hides away in my system, let's me used balanced inputs, and doesn't get particularly hot, so I am quite happy with this use-case.
 
I purchased two USB cooling fans from Amazon yesterday, one to sit underneath each amp (like I saw someone do in the review thread), the fans have already arrived. I don't want to take chances until a lot of these monos have safely run at operating temperature for a while. I still await my amps., no word yet......
My fans came in and I am using them set to the Medium speed setting. They're not audible at that setting from my listening position about a dozen feet away. When I touch the enclosures after a few hours of nonstop playback, they feel moderately warm, maybe like 85° F. Awesome!

IMG_3180.jpeg


Please disregard the clutter; hard to keep things tidy with 6- and 4-year-old sons. Also, the doorstops are needed to hold the V3 Monos in place because they’re too light and my cables drag them down.

-Ed
 
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My fans came in and I am using them set to the Medium speed setting. They're not audible at that setting from my listening position about a dozen feet away. When I touch the enclosures after a few hours of nonstop playback, they feel moderately warm, maybe like 85° F. Awesome!

View attachment 377656

Please disregard the clutter; hard to keep things tidy with 6- and 4-year-old sons. Also, the doorstops are needed to hold the V3 Monos in place because they’re too light and my cables drag them down.

-Ed
Look at those lovely valves on your Freya + :)
 
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