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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 8 1.5%
  • 2. Not terrible (postman panther)

    Votes: 14 2.6%
  • 3. Fine (happy panther)

    Votes: 109 20.2%
  • 4. Great (golfing panther)

    Votes: 409 75.7%

  • Total voters
    540
Better having long XLR signal cables than long speaker cables. Also, having two separates gives more overall stability. Whether one really needs the latter could be a discussion (in which I'm not interested, however).
Symmetrical input connections are shielded for a reason. This is because many interferences can be induced in these cables, unlike speaker cables. Speaker cables can be laid almost anywhere without causing issues. Therefore, it is logically advisable to use longer speaker cables rather than longer input cables.
 
Better having long XLR signal cables than long speaker cables. Also, having two separates gives more overall stability. Whether one really needs the latter could be a discussion (in which I'm not interested, however).
Symmetrical input connections are shielded for a reason. This is because many interferences can be induced in these cables, unlike speaker cables. Speaker cables can be laid almost anywhere without causing issues. Therefore, it is logically advisable to use longer speaker cables rather than longer input cables.
In most hifi installations the cables are short enough and interference low enough that it makes no practical difference which you do.
 
Could someone explain to me why you are buying mono amplifiers with the TPA3255 chip?

If you only have 4 Ohm speakers, there is no difference in output power between mono and stereo modes.
I don't only have 4 ohm speaker, why are you questioning my decision? I didn't borrow money from you to buy these.
 
You don't marry with someone or have a child based on scientific evidence, there are some things that you do because you want it

Two decent monoblocks with good power for approx 300 USD ... come on :)

Maybe and surely in 99% of the use cases there's no difference at all, but you know two monoblocks are the best in amplification (best power available, best crosstalk, best positioning near / far speakers, blah blah).

So ... what's wrong with that? I can't understand why we complicate to the heavens something really easy.
 
Maybe and surely in 99% of the use cases there's no difference at all, but you know two monoblocks are the best in amplification (best power available, best crosstalk, best positioning near / far speakers, blah blah).
So ... what's wrong with that? I can't understand why we complicate to the heavens something really easy.
Nothing at all wrong, and it will sound better to us because we believe mono blocks with PFFB theoretically could sound better. I have 2 on the way while owning another perfectly fine TPA3255 amp.

Still, it would be cheaper with the same result if I believed a $50 acoustic brick or $175 audio cables sounded better. Being scientific cost me a few bucks more.
 
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Nothing at all wrong, and it will sound better to us because we believe mono blocks with PFFB theoretically could sound better. I have 2 on the way while owning another perfectly fine TPA3255 amp.

Still, it would be cheaper with the same result if I believed a $50 acoustic brick or $175 audio cables sounded better. Being scientific cost me a few bucks more.

The same result can be achieved with something even cheaper, yes ... maybe the audio industry educated us to think that 300 USD isn't an "exotic" price tag after all.
 
it will sound better to us because we believe mono blocks with PFFB theoretically could sound better.
But measurements do tell that it may not be the case, a similarity measured stereo amplifier will have same output capabilities.
Crosstalk is something that gets benefit from mono setup but if stereo amplifier has more than decent crosstalk then this becomes no benefit.
And to summarize, there are no benefits in terms of available power output, frequency response, distortion (sometimes distortion is even a bit worse), etc.
However, there could be many implementation flexibility used cases for monoblock.
* All these are subject to these TPA3255 implementations, a different chip or module would be different in this regard.
Most of the times, “monoblock” thingy is nothing other than Audiophile or selling BS.

P.E. There is nothing wrong in choosing whatever suits one, it’s one’s own choice & decision after all.
 
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Sometimes it is necessary to reset your perceptions and expectations. I recently picked up a basic, stereo, single-ended Fosi V3, and swapped it in place of my pair of ZA3s run as monoblocs with balanced connections, just to see what difference there would be. Would I say there is no difference at all? No. Would I say that the difference is very, very small? Absolutely. Granted, your results would likely be different, especially if you’re running harder-to-drive speakers than I am (KEF LS50 Metas reinforced by an SVS SB-3000 subwoofer). For the V3, I used a 48V/10A power supply. When running the dual ZA3s, each one got a 48V/10A power supply.

Afterwards, I swapped back to the ZA3s, but hooked them back up single-ended instead of balanced, and it sounded basically the same as when using balanced input (once volume-matched).

-Ed

PS By the way, these things are getting comically small. The standard V3 is an absurdly small device considering the immense volume levels that which it is capable of driving a pair of LS50 Metas to without distortion/clipping when paired with a 48V/10A power supply. It is even dwarfed completely by a single ZA3. Are the V3 Monos the same size as the stereo V3?
 
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Could someone explain to me why you are buying mono amplifiers with the TPA3255 chip?

If you only have 4 Ohm speakers, there is no difference in output power between mono and stereo modes.

Price/performance: of all the amplifiers in the blue section, this seems to be cheapest per channel. And in a surround-setup, having the same amplifier for left-right-center might be an advantage (atleast it looks good...).
 
It seems there is a discussion about the choice of audio components. The crux of the question revolves around the purchase of monoblocks, which are individual amplifiers for each channel, as opposed to a stereo or multi-channel amplifier. Here are some possible reasons why someone might choose monoblocks, even if there is no apparent difference in output power:

1. **Sound Quality**: Some audiophiles believe that monoblocks provide better channel separation and less crosstalk between channels, leading to a clearer and more precise soundstage.
2. **Power Reserves**: Monoblocks may have larger power reserves, meaning they can deliver stable performance even at high volumes or during demanding passages.
3. **Specialization**: Since monoblocks only amplify one channel, they can be specifically optimized for this task, which can lead to potentially higher performance.
4. **Aesthetics and Status**: For some, owning monoblocks is also a matter of personal taste and status symbol.

Regarding speakers, the decision to opt for 4-ohm speakers might involve similar considerations. It could be about compatibility with certain amplifiers or a preference for the sound characteristics that 4-ohm speakers can offer.

Ultimately, such decisions are often subjective and based on personal preferences, the specific setup, and the goals of the listener. It's important that everyone makes their own choices based on what's best for their listening experience.
 
I was wondering why the level of discourse on the thread had suddenly improved. :facepalm:
"Let me ChatGPT that for you" is the new "Let me Google that for you."
 
It seems there is a discussion about the choice of audio components. The crux of the question revolves around the purchase of monoblocks, which are individual amplifiers for each channel, as opposed to a stereo or multi-channel amplifier. Here are some possible reasons why someone might choose monoblocks, even if there is no apparent difference in output power:

1. **Sound Quality**: Some audiophiles believe that monoblocks provide better channel separation and less crosstalk between channels, leading to a clearer and more precise soundstage.
2. **Power Reserves**: Monoblocks may have larger power reserves, meaning they can deliver stable performance even at high volumes or during demanding passages.
3. **Specialization**: Since monoblocks only amplify one channel, they can be specifically optimized for this task, which can lead to potentially higher performance.
4. **Aesthetics and Status**: For some, owning monoblocks is also a matter of personal taste and status symbol.

Regarding speakers, the decision to opt for 4-ohm speakers might involve similar considerations. It could be about compatibility with certain amplifiers or a preference for the sound characteristics that 4-ohm speakers can offer.

Ultimately, such decisions are often subjective and based on personal preferences, the specific setup, and the goals of the listener. It's important that everyone makes their own choices based on what's best for their listening experience.
This thread is for Fosi v3 mono, we have all the data for other same chip mono & stereo amplifiers.
Generic mono vs stereo channel amplifier comparison won’t help here, it needs to be focused on subjected product.
 
Please don't post AI-generated text without clearly labeling it as such.

@amirm @BDWoody Please consider making this a forum rule :)
I thought we are here to learn from others wisdom, experience and exposure but things are going in other directions now :facepalm:

I realized I lost politeness, just meant to say that we totally value any wisdom and experience, and opinions too, however should try to avoid such AI answers if possible.
Or probably tag with the source of information to be clear!
 
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I just “pledged” for 4 of these with the requisite power supplies, filters, etc. As a collector and lover of Acoustats and Magnepans l genuinely need this kind of performance. They’re all power hungry and my Acoustat Spectra 1100s dip to below 2 ohms at very high frequencies. These will be icing on the cake vs. the Fosi V3 Stereo amplifiers I’m currently using to drive them with DSP crossovers and EQ. What a time to be alive.
 
It seems there is a discussion about the choice of audio components. The crux of the question revolves around the purchase of monoblocks, which are individual amplifiers for each channel, as opposed to a stereo or multi-channel amplifier. Here are some possible reasons why someone might choose monoblocks, even if there is no apparent difference in output power:

1. **Sound Quality**: Some audiophiles believe that monoblocks provide better channel separation and less crosstalk between channels, leading to a clearer and more precise soundstage.
2. **Power Reserves**: Monoblocks may have larger power reserves, meaning they can deliver stable performance even at high volumes or during demanding passages.
3. **Specialization**: Since monoblocks only amplify one channel, they can be specifically optimized for this task, which can lead to potentially higher performance.
4. **Aesthetics and Status**: For some, owning monoblocks is also a matter of personal taste and status symbol.

Regarding speakers, the decision to opt for 4-ohm speakers might involve similar considerations. It could be about compatibility with certain amplifiers or a preference for the sound characteristics that 4-ohm speakers can offer.

Ultimately, such decisions are often subjective and based on personal preferences, the specific setup, and the goals of the listener. It's important that everyone makes their own choices based on what's best for their listening experience.

"Believe that"
"May Have"
"Can be"
"Possible Reasons"

It doesn't matter what is believed, what something may have, or can be. What possible reasons there might be.

It simply matters what is! And this is what measurements tell us.
 
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