Fosi v3 Mono | TPA3255 PFFB | Balanced | [First Look from Fosi FB]

[Joe Smith]

Solid state preamp soon! Please, please!

 

[Matias]

Some measurements here:

Amplifier - V3 Monoblock with PFFB Implementation is Coming!

We know many of our fans are waiting for this monoblock! We'll post updates about this amazing amp in this thread. Jan 25 Update: Let's take a glance at some measurements first PFFB technology was implemented and load Independence was achieved! SINAD March 21 Update: April 1 Update...

community.fosiaudio.com

 

[Guddu]

Some measurements here:

Amplifier - V3 Monoblock with PFFB Implementation is Coming!

We know many of our fans are waiting for this monoblock! We'll post updates about this amazing amp in this thread. Jan 25 Update: Let's take a glance at some measurements first PFFB technology was implemented and load Independence was achieved! SINAD March 21 Update: April 1 Update...

community.fosiaudio.com

Let’s add here for those who don’t have access to Fosi’s forum:

 

[kemmler3D]

Some of the comments on the thread re this amp on the Fosi Facebook page...oh dear, oh dear, oh dear...

A current customer seems to be disappointed because it will use feedback (which he doesn't trust) and that Fosi doesn't supply a nice audiophile grade linear power supply.

Needless to say, when I pointed out the similarities between Class D and SMPS technology, the need for feedback, etc., he replied that he wasn't schooled in electronics but just wanted the best sound possible.

Even the most sophisticated arguments against feedback I've seen don't seem to hold water... (not that I've really looked)... people seem to be against feedback without even realizing what it is or why they should avoid it.

 

[Doodski]

Even the most sophisticated arguments against feedback I've seen don't seem to hold water... (not that I've really looked)... people seem to be against feedback without even realizing what it is or why they should avoid it.

When I studied the fundamentals of semi conductor devices we beat to death feedback versus no feedback by using circuit analysis and calculated everything about the comparative circuits. I was a subjective mess before the study and had many false ideas about feedback and other stuff too. The result of all that maths work calculating all the various stuff comparing feedback to no feedback was that I realized as the study was intended to indicate for us that feedback is not a bad thing like the legends and urban rumors state. It is a mathematically sooper accurate and effective way operation that has benefits that outweigh no feedback.

 

[MCH]

Even the most sophisticated arguments against feedback I've seen don't seem to hold water... (not that I've really looked)... people seem to be against feedback without even realizing what it is or why they should avoid it.

Well my DAC can output 10 Volts, so not an issue at all for me but if I was feeling it with a 1v dongle like some people do I would not trade 10db gain for 10db sinad. Just my opinion.

 

[Talisman]

Well my DAC can output 10 Volts, so not an issue at all for me but if I was feeling it with a 1v dongle like some people do I would not trade 10db gain for 10db sinad. Just my opinion.

Basically if you connect it directly to Klipschorn you don't need the amplifier.....

 

[Tangband]

Probably external PSU :/ I hope "auto" works on RCA also so trigger is not needed.
If auto works on RCA I'm buying two.

Good with an external SMPS supply - If it fails then its easy to replace.

 

[sarieri]

It really needs to be sub $200. If it is $200, I would spend the extra $90 or so and get the Audiophonics in a nice case with internal PSU. Not a fan of external PSUs, and even less of two external PSUs.

AUDIOPHONICS AP300-S2503E Power Amplifier 3E AUDIO 260-2-29A PFFB

The Audiophonics AP300-S2503E is a stereo power amplifier featuring a 3e Audio PFFB amplifier module. This enables it to develop 2x250W of power under 4Ω while delivering exceptional sound quality, combining precision and dynamics.

www.audiophonics.fr

But dual mono is not equivalent to stereo.

 

[Guddu]

But dual mono is not equivalent to stereo.

Right.
But 3e is, by far, one of the best TPA3255 PFFB module available with quality components and great review/measurements.

On the other hand, we haven't seen any real meaningful additional power addition on TPA3255 in mono vs Stereo, not yet at least.

On a comparison, Audiophonics 3e amplifier probably would make more sense than anything else on similar price point when stereo is desired (as in TPA3255 based amplifier with internal PSU).

PE. I should also add that we might have this new Fosi v3 mono as good performer as 3e which would make this comparison end with personal choice without going wrong with any of these two.
BTW, Audiophonics 3e TPA3255 amplifier seems priced a bit high in MHO for what it is and I believe Fosi can do much better from price prospective.
*** Topping PA7 is another excellent TPA3255 contender if external PSU isn't a concern, around $400 - 500 mark.

 

[sejarzo]

I have become uneasy with Topping's reliability record as of late, so their products are off my list of potential buys.

Replacing the internal PSU in any of the single-case alternatives is certainly more involved than just plugging in a replacement external unit, but it wouldn't be a horribly involved task--assuming a direct or near-direct replacement is available. The only components that ever failed in a power amp I've owned since the 1970s are output transistors.

 

[sejarzo]

Hope you understand the degree of eagerness some people have here for this .

Especially those of us who have ZA3s in our Fosi shopping cart.

 

[surroundman]

It does seem like a good product. However, I fear that prices are increasing way too much after releasing products so often. If we have members who hope this mono amp to be under $200 are we still talking about budget (or even good value!) products!? I don't know ... I feel like the more we praise the recently released gear, the more we make the manufacturers believe they can charge a pinch more.

 

[Guddu]

Especially those of us who have ZA3s in our Fosi shopping cart.

Think about those who bought ZA3’s for dual - mono setup just 1 month back

 

[sejarzo]

If I had bought the ZA3 or V3 earlier, I wouldn't be trading up now. I have Q150s as an interim solution while we decided when and where to downsize so either of those would be adequate....but a couple of these monoblocks would be a more future-proof buy.

 

[YesChickenNuggets]

I notice that with the volume knob turned higher, the tweeter hiss is also higher, if I don't need the output, I'd prefer less hiss during silence. Does the removal of the volume knob mean that I will not be able to do this small trick and it will always be hissy? Will the higher sinad reduce the hiss?

 

[darrellc]

interesting but then I think instead of 2x of these v3 pffb monoblocks, why not a 2 channel Nc502mp hyped amp? Probably won’t cost that much more.

 

[Guddu]

I notice that with the volume knob turned higher, the tweeter hiss is also higher, if I don't need the output, I'd prefer less hiss during silence. Does the removal of the volume knob mean that I will not be able to do this small trick and it will always be hissy? Will the higher sinad reduce the hiss?

I don’t have any tweeter hiss with A07 Max and Topping PA7 (don’t remember how it was with ZA3) with ELAC DBR62 even on max vol.
I will be surprised if this amp will have any hiss, may be with super sensitive speakers like some horns etc. if at all.
Fosi surely have good experience and exposure now after v3 and ZA3 amps.

 

[Guddu]

interesting but then I think instead of 2x of these v3 pffb monoblocks, why not a 2 channel Nc502mp hyped amp? Probably won’t cost that much more.

Right, there is some comparison wrt hypex 250 amps few posts back.

 

[Talisman]

It does seem like a good product. However, I fear that prices are increasing way too much after releasing products so often. If we have members who hope this mono amp to be under $200 are we still talking about budget (or even good value!) products!? I don't know ... I feel like the more we praise the recently released gear, the more we make the manufacturers believe they can charge a pinch more.

I don't understand this reasoning.
If we ask (and obtain) from the producers greater engineering efforts, greater attention to materials, better performance, greater reliability, etc., then it will also be right for the producers to ask for an increase in the premium for their work. I don't think there is anything strange or absurd in this.