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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: 13 2.5%
  • 3. Fine (happy panther)

    Votes: 104 19.7%
  • 4. Great (golfing panther)

    Votes: 403 76.3%

  • Total voters
    528
Honestly, I have never ever run into any of these problems running premade cables with swappable ends and just using the banana plug option. They’re tight enough, they go in fine, they don’t budge, and they sound fine.

-Ed
Same here but you know how this hobby is lol
 
Any ideas which one would be the best solution for:

RCA connections
and being able to balance left and right?
Yamaha A-S301 or any other regular amp. Same price region too.
 
Honestly, I have never ever run into any of these problems running premade cables with swappable ends and just using the banana plug option. They’re tight enough, they go in fine, they don’t budge, and they sound fine.

-Ed

I use these with slat springs for everything that does not have Speakon.

516cwp-dL0L._AC_SL1500_.jpg
 
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Honestly, I have never ever run into any of these problems running premade cables with swappable ends and just using the banana plug option. They’re tight enough, they go in fine, they don’t budge, and they sound fine.

-Ed
I have used banana extensively with instrumentation and they are notorious for poor connections that result in erroneous metering.
 
I have used banana extensively with instrumentation and they are notorious for poor connections that result in erroneous metering.
Do spades perform better in this respect?
 
Do spades perform better in this respect?
I never used spades for instrumentation metering so I never got to see if the connections where poor or not. A tight screwed down spade should be good though. :D
 
Do spades perform better in this respect?
I mean, yes, but occasionally the speaker terminals need to be tightened because they loosen over time from vibrations.
 
I have perfectly good cables that I bought with threaded ends that take my choice of screw-on spades or screw-on banana plugs. I won’t just put aside good cables to try and switch to bare wire.

-Ed
 
The 2Ω output that Amir measured is 100W short of the TPA3255's specs:

Isn't it likely that a 10A supply would get the V3 Mono closer to spec?
I wish if I could tell anything about 2ohm load output capabilities, but don’t see any point in getting too much into theory myself for this.
Most the speakers dip down around 4ohm, and I see no reason to jump from 48v 5a to 10a for such a speaker.
After all, people but 350w amplifier even though they only use 50w generally in practice, those who can.
So why not 10a psu!

PE. And even if it can run amp to its limits, I won’t dream of doing that myself, and so I won’t advertise anyone else as well.
 
Yamaha A-S301 or any other regular amp. Same price region too.
Unfortunately this is too big. I need something small.

Therefore I would also like to avoid additional devices to produce volume control/balance.

Any other ideas?
 
Unfortunately this is too big. I need something small.

Therefore I would also like to avoid additional devices to produce volume control/balance.

Any other ideas?
Douk H7 is probably the closest thing to what you want since it has separate volumes for left and right channels. They are releasing a Douk H7 Pro model that is an improvement on the original H7, also.


-Ed
 
TPA3255 PBTL Mono won't gain anything (significant or useful) from 48v 5a to 10a, no benefit.

@Fosi Audio Its a good idea to add a table or chart on your Fosi v3 mono product page with output power on different PSU options.
Obviously not the same amplifier, but interestingly enough, the Douk H7 Pro, which is a stereo amplifier also based on the same Texas Instruments chip (so similar to, say, the Fosi ZA3 with stereo VUs in place of a mono mode and full spectrum stereo RCA outputs in place of a filtered subwoofer output), and it shows a power increase going 48V 10A versus 48V 5A:
IMG_2611.jpeg
 
PFFB On or Off is not a specified condition for the graph in TI's datasheet.

As for the supply voltage, just take a look at the graph in my link.
The graphs are with it off. The amplifiers gain is reduced by the amount of feedback used, but total power will depend on the input buffer gain
 
Obviously not the same amplifier, but interestingly enough, the Douk H7 Pro, which is a stereo amplifier also based on the same Texas Instruments chip (so similar to, say, the Fosi ZA3 with stereo VUs in place of a mono mode and full spectrum stereo RCA outputs in place of a filtered subwoofer output), and it shows a power increase going 48V 10A versus 48V 5A:View attachment 363617

Seems like you are confusing stereo output power to PBTL mono power output.
Try to find a similar table for PBTL/mono amplifier to see what difference does it make potentially.

This is the reason why PFFB Stereo implementation is practically more beneficial compared to mono implementation for use in general for TPA3255 based topologies.
 
This is the reason why PFFB Stereo implementation is practically more beneficial compared to mono implementation for use in general for TPA3255 based topologies.
If you are going to be using the amps to the limit of their power, thermal behaviour is going to become very relevant, and in this scenario mono implementation has an important advantage, for obvious reasons.
 
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