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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 14 2.2%
  • 2. Not terrible (postman panther)

    Votes: 20 3.1%
  • 3. Fine (happy panther)

    Votes: 123 19.2%
  • 4. Great (golfing panther)

    Votes: 485 75.5%

  • Total voters
    642
I see there’s an option to buy these without a power supply…If not from Fosi where else can you get one?
Ebay in Germany offers V3 monos without power supplies.
But those are indirect offerings from Fosi Audio too, delivering items from German warehouses if needed...
 
Or will have something else by then. I just looked at the regular V3. It has holes on both the top and bottom.
What's need to be cooled is the bottom where the chip is,holes only on top may not do much if no holes at the bottom too exist so to exchange heat.
And they will reduce the already inadequate heat dissipating area even more.

I would leave it be as is for as long as it lasts although I admit it will be fun to play with it after warranty,just to see.
 
What's need to be cooled is the bottom where the chip is,holes only on top may not do much if no holes at the bottom too exist so to exchange heat.
And they will reduce the already inadequate heat dissipating area even more.
There's also the heat from the output inductors and regulators which often get forgotten.
 
It depends, what each measure will do for those previously measured temperatures (top, bottom, casing as a whole).
... and it needs redoing the thermal paste as usual, as it probably has been scrapped off during the action of removing (and insertion) the PCB from the case...
 
That may be for people who already have power supplies from previous Fosi amps. I've got an extra 48v that came with a regular V3 that I'm not using.
Thanks. The reason I ask is because Aliexpress has a sale currently (which works out cheaper than Fosi direct) but only have the Amp without PS in stock so I was wondering if there is a ‘universal’ one available or if any other 48v 5amp would work..
 
I see there’s an option to buy these without a power supply…If not from Fosi where else can you get one?
There's an AIYIMA 48v 5A that is cheaper. No idea of it's better or worse though, says 6.3A max
 
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A poster on Fosi's Facebook is using this Power supply , has 48V 10A to power both V3monos. Any thoughts on this? This is used for DC connection.
 
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Hello there,

I'm new to the forum. So far I have only been a silent reader. However, I now have a few questions that are giving me a bit of a headache and I was hoping that you might be able to help me.

I currently have a 7.1 system with OLED, projector etc. in my living room for gaming, watching films and series and other multimedia. I also enjoy listening to music a lot. Of course, if it's not multi-channel sources, I prefer stereo.

My chain for this currently looks like this:
WiiM Pro Plus > optical cable > Marantz SR6011 (in 'pure direct' mode) > RCA Pre Out > Fosi V3 stereo amplifier > to my favourite speakers.
The Fosi amp is turned up all the way. The volume is controlled via the Marantz.
I really enjoy listening to the whole thing.
Nevertheless, I ordered two Fosi V3 monos at the end of July, which have not yet been delivered. As I was unsure whether the monos would already have the corrected phase, I asked again and it was confirmed.
I ordered the monos with a 10 A power supply and the filter. Would it make more sense to power them separately with the existing 48 V 5 A GaN power supply of my stereo amp (and buy a second one)?

There was also a good offer for the Topping DX5 DAC, which I also ordered and which was delivered yesterday.

My plan was as follows:
Connect the WiiM Pro Plus to the Topping DX5 via an optical cable. From this with XLR to the monos and to my two speakers. I could then continue to connect the Marantz AVR to the monos via RCA Pre Out to continue using my speakers in the 7.1 system and simply switch the input on the monos as required.
So far so good.

My idea was actually to set the volume on the WiiM to 100% and adjust it on the Topping DAC (in 'Pre Amp' mode).
Actually, I was of the opinion that if a device like the Topping DAC has a pre-amp mode and a volume control, you could use it without any major worries.
But then I read the horror stories from one or a few users that their Topping E70 suddenly switched to full volume while listening and that this can happen with all digital volume controls.

I don't want to damage my beloved speakers or my ears. So now another question. Which of the following solutions would you advise me to use?

1. use the Topping DX5 for volume control as originally planned, because I'm just too worried.
2. to set the Topping to DAC mode (with full volume output and without the possibility of control) and to control the volume via the WiiM. However, this is also a digital volume control. But at least I could set a maximum volume with it.
3. turn the Topping up to full volume, then set the WiiM to the maximum volume at which I would listen and then adjust the volume while listening via the DAC. This would give me two 'safeguards', so to speak, with which a possible error would certainly not occur at the same time. The question is: does this setting result in any loss of sound quality?
4. a completely different solution? I don't want the chain to be any longer if it's not absolutely necessary.

I am also someone who always checks the volume before playing. But the problem is that I often listen without my wife being present. And since I'm a wheelchair user, I can't just jump up and rip the cables out of the wall in an emergency. :D

Questions upon questions.
Sorry for the long text and thank you in advance for your patience and any advice.
 
Just out of curiosity what was the kick starter pricing, for two amps and one 48v 10amp brick?
 
Hello there,

I'm new to the forum. So far I have only been a silent reader. However, I now have a few questions that are giving me a bit of a headache and I was hoping that you might be able to help me.

I currently have a 7.1 system with OLED, projector etc. in my living room for gaming, watching films and series and other multimedia. I also enjoy listening to music a lot. Of course, if it's not multi-channel sources, I prefer stereo.

My chain for this currently looks like this:
WiiM Pro Plus > optical cable > Marantz SR6011 (in 'pure direct' mode) > RCA Pre Out > Fosi V3 stereo amplifier > to my favourite speakers.
The Fosi amp is turned up all the way. The volume is controlled via the Marantz.
I really enjoy listening to the whole thing.
Nevertheless, I ordered two Fosi V3 monos at the end of July, which have not yet been delivered. As I was unsure whether the monos would already have the corrected phase, I asked again and it was confirmed.
I ordered the monos with a 10 A power supply and the filter. Would it make more sense to power them separately with the existing 48 V 5 A GaN power supply of my stereo amp (and buy a second one)?

There was also a good offer for the Topping DX5 DAC, which I also ordered and which was delivered yesterday.

My plan was as follows:
Connect the WiiM Pro Plus to the Topping DX5 via an optical cable. From this with XLR to the monos and to my two speakers. I could then continue to connect the Marantz AVR to the monos via RCA Pre Out to continue using my speakers in the 7.1 system and simply switch the input on the monos as required.
So far so good.

My idea was actually to set the volume on the WiiM to 100% and adjust it on the Topping DAC (in 'Pre Amp' mode).
Actually, I was of the opinion that if a device like the Topping DAC has a pre-amp mode and a volume control, you could use it without any major worries.
But then I read the horror stories from one or a few users that their Topping E70 suddenly switched to full volume while listening and that this can happen with all digital volume controls.

I don't want to damage my beloved speakers or my ears. So now another question. Which of the following solutions would you advise me to use?

1. use the Topping DX5 for volume control as originally planned, because I'm just too worried.
2. to set the Topping to DAC mode (with full volume output and without the possibility of control) and to control the volume via the WiiM. However, this is also a digital volume control. But at least I could set a maximum volume with it.
3. turn the Topping up to full volume, then set the WiiM to the maximum volume at which I would listen and then adjust the volume while listening via the DAC. This would give me two 'safeguards', so to speak, with which a possible error would certainly not occur at the same time. The question is: does this setting result in any loss of sound quality?
4. a completely different solution? I don't want the chain to be any longer if it's not absolutely necessary.

I am also someone who always checks the volume before playing. But the problem is that I often listen without my wife being present. And since I'm a wheelchair user, I can't just jump up and rip the cables out of the wall in an emergency. :D

Questions upon questions.
Sorry for the long text and thank you in advance for your patience and any advice.
Welcome
I keep it simple as possible, always have a Dac/preamp with Volume displayed as default and make sure it comes with remote control, so you can mute if need be, without struggling to reach. I'm sure someone can help in detail.
 
Hello there,

I'm new to the forum. So far I have only been a silent reader. However, I now have a few questions that are giving me a bit of a headache and I was hoping that you might be able to help me.

I currently have a 7.1 system with OLED, projector etc. in my living room for gaming, watching films and series and other multimedia. I also enjoy listening to music a lot. Of course, if it's not multi-channel sources, I prefer stereo.

My chain for this currently looks like this:
WiiM Pro Plus > optical cable > Marantz SR6011 (in 'pure direct' mode) > RCA Pre Out > Fosi V3 stereo amplifier > to my favourite speakers.
The Fosi amp is turned up all the way. The volume is controlled via the Marantz.
I really enjoy listening to the whole thing.
Nevertheless, I ordered two Fosi V3 monos at the end of July, which have not yet been delivered. As I was unsure whether the monos would already have the corrected phase, I asked again and it was confirmed.
I ordered the monos with a 10 A power supply and the filter. Would it make more sense to power them separately with the existing 48 V 5 A GaN power supply of my stereo amp (and buy a second one)?

There was also a good offer for the Topping DX5 DAC, which I also ordered and which was delivered yesterday.

My plan was as follows:
Connect the WiiM Pro Plus to the Topping DX5 via an optical cable. From this with XLR to the monos and to my two speakers. I could then continue to connect the Marantz AVR to the monos via RCA Pre Out to continue using my speakers in the 7.1 system and simply switch the input on the monos as required.
So far so good.

My idea was actually to set the volume on the WiiM to 100% and adjust it on the Topping DAC (in 'Pre Amp' mode).
Actually, I was of the opinion that if a device like the Topping DAC has a pre-amp mode and a volume control, you could use it without any major worries.
But then I read the horror stories from one or a few users that their Topping E70 suddenly switched to full volume while listening and that this can happen with all digital volume controls.

I don't want to damage my beloved speakers or my ears. So now another question. Which of the following solutions would you advise me to use?

1. use the Topping DX5 for volume control as originally planned, because I'm just too worried.
2. to set the Topping to DAC mode (with full volume output and without the possibility of control) and to control the volume via the WiiM. However, this is also a digital volume control. But at least I could set a maximum volume with it.
3. turn the Topping up to full volume, then set the WiiM to the maximum volume at which I would listen and then adjust the volume while listening via the DAC. This would give me two 'safeguards', so to speak, with which a possible error would certainly not occur at the same time. The question is: does this setting result in any loss of sound quality?
4. a completely different solution? I don't want the chain to be any longer if it's not absolutely necessary.

I am also someone who always checks the volume before playing. But the problem is that I often listen without my wife being present. And since I'm a wheelchair user, I can't just jump up and rip the cables out of the wall in an emergency. :D

Questions upon questions.
Sorry for the long text and thank you in advance for your patience and any advice.
Regarding "Would it make more sense to power them separately with the existing 48 V 5 A GaN power supply of my stereo amp (and buy a second one)"?
I use the 10 A and somewhere there is a filter I've yet to plug in ... my two monos sit adjacent to a decent sized TV screen, and then on to a pair of speakers (also special to me).

Many will chime in here saying go with the two supplies. I would also if my plug sockets and system layout benefited. As it is right now the additional supply would simply join the others behind my television!

The best volume control I have yet to find is a relay switched device - it's 'physical' and so I don't worry about sudden max volume surging through to my speakers. It is also fully balanced, but gives dual single ended also, from balanced input, useful for line level connection to subwoofer(s).

It is however an additional step in the chain, and so not absolutely necessary. Appears to be for chinese enthusiasts (and not export market dumping)! Very transparent! You need to like blue leds though... I find it superb with balanced in to balanced out, and you could probably run a cable to have it near by your location, benefiting from balanced cable lengths.

I appreciate this is dinosaur stuff not having a remote control, but I could only find it with manual control... but it just doesn't seem to get in the way of the (balanced) signal ... sounding superbly as if it is not there at all!

And for not all that much more than an additional power supply!
 
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A poster on Fosi's Facebook is using this Power supply , has 48V 10A to power both V3monos. Any thoughts on this? This is used for DC connection.

I went with two power supplies and have them plugged into different, separate outlets. The extra space taken up by one more power brick is not a big deal.
 
Hello there,

I'm new to the forum. So far I have only been a silent reader. However, I now have a few questions that are giving me a bit of a headache and I was hoping that you might be able to help me.

I currently have a 7.1 system with OLED, projector etc. in my living room for gaming, watching films and series and other multimedia. I also enjoy listening to music a lot. Of course, if it's not multi-channel sources, I prefer stereo.

My chain for this currently looks like this:
WiiM Pro Plus > optical cable > Marantz SR6011 (in 'pure direct' mode) > RCA Pre Out > Fosi V3 stereo amplifier > to my favourite speakers.
The Fosi amp is turned up all the way. The volume is controlled via the Marantz.
I really enjoy listening to the whole thing.
Nevertheless, I ordered two Fosi V3 monos at the end of July, which have not yet been delivered. As I was unsure whether the monos would already have the corrected phase, I asked again and it was confirmed.
I ordered the monos with a 10 A power supply and the filter. Would it make more sense to power them separately with the existing 48 V 5 A GaN power supply of my stereo amp (and buy a second one)?

There was also a good offer for the Topping DX5 DAC, which I also ordered and which was delivered yesterday.

My plan was as follows:
Connect the WiiM Pro Plus to the Topping DX5 via an optical cable. From this with XLR to the monos and to my two speakers. I could then continue to connect the Marantz AVR to the monos via RCA Pre Out to continue using my speakers in the 7.1 system and simply switch the input on the monos as required.
So far so good.

My idea was actually to set the volume on the WiiM to 100% and adjust it on the Topping DAC (in 'Pre Amp' mode).
Actually, I was of the opinion that if a device like the Topping DAC has a pre-amp mode and a volume control, you could use it without any major worries.
But then I read the horror stories from one or a few users that their Topping E70 suddenly switched to full volume while listening and that this can happen with all digital volume controls.

I don't want to damage my beloved speakers or my ears. So now another question. Which of the following solutions would you advise me to use?

1. use the Topping DX5 for volume control as originally planned, because I'm just too worried.
2. to set the Topping to DAC mode (with full volume output and without the possibility of control) and to control the volume via the WiiM. However, this is also a digital volume control. But at least I could set a maximum volume with it.
3. turn the Topping up to full volume, then set the WiiM to the maximum volume at which I would listen and then adjust the volume while listening via the DAC. This would give me two 'safeguards', so to speak, with which a possible error would certainly not occur at the same time. The question is: does this setting result in any loss of sound quality?
4. a completely different solution? I don't want the chain to be any longer if it's not absolutely necessary.

I am also someone who always checks the volume before playing. But the problem is that I often listen without my wife being present. And since I'm a wheelchair user, I can't just jump up and rip the cables out of the wall in an emergency. :D

Questions upon questions.
Sorry for the long text and thank you in advance for your patience and any advice.

Unless you need extra features or extra inputs from the Topping, you can eliminate it and just use the Wiim Pro Plus as your preamp, streamer and dac. The Topping won't sound any better than the dac in the Pro Plus.
 
Power unit I use the Mean Well LRS-350-48 unit. Grounding is also possible, allowing for cleaner DC current.
 
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