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

[gwing]

It's probably also fair to say that the expected number of sales for a monoblock are likely to be significantly lower than for a stereo amp (especially if the monoblock isn't really significantly better for typical speakers) and therefore the costs per unit are going to be higher.

 

[312elements]

It's probably also fair to say that the expected number of sales for a monoblock are likely to be significantly lower than for a stereo amp (especially if the monoblock isn't really significantly better for typical speakers) and therefore the costs per unit are going to be higher.

When you combine that with the assumption that a lot of people in the market for a 3255 based amp already bought one, I think you're really on to something.

 

[mike70]

This new Fosi is operating in PBTL. (Mono). That only brings about 30% more power under 4R and more or less 10% under 8R vs BTL (Stereo).
So the main interest here it is drive 2R loads...

I would wait for the Stereo version instead... This new Mono PFFB has a limited interest....
You can read the review between the 3E Audio Mono PFFB vs the Stereo PFFB to understand this point.

in other way, think about people that wanted to have a pair of monoblocks since ... forever ... where you'll find a pair in the Fossi prices?
so, it can be a great (great) opportunity to take a chance on that ... brain matters ... but heart matters also

as informed consumers, we can do that, you pay a little more (not stratospheric prices) to have a separated case / power supply ... and i thank ASR to let me decide in that way (and not thinking i take a great product based on the looks / brand / marketing)

 

[daniboun]

in other way, think about people that wanted to have a pair of monoblocks since ... forever ... where you'll find a pair in the Fossi prices?
so, it can be a great (great) opportunity to take a chance on that ... brain matters ... but heart matters also

as informed consumers, we can do that, you pay a little more (not stratospheric prices) to have a separated case / power supply ... and i thank ASR to let me decide in that way (and not thinking i take a great product based on the looks / brand / marketing)

Makes sense but who says two mono blocks, says two PSU bricks, says I double the consumption and no time for the planet)
It remains ironic of course) But it would be cool to see a Stereo amp instead which would be much more affordable and rational

 

[charlielaub]

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

I can give some first hand testimony about Topping products. I own four DACs from them. I have also owned but sold off a PA5 amp and another DAC. I never experienced a problem with any of these products.

It's like any low cost electronics - they are not going to last forever like an old school electronics component build with thru hole components, etc. This is the reality that one must confront in exchange for paying only a couple of hundred dollars for them!

 

[daniboun]

I can give some first hand testimony about Topping products. I own four DACs from them. I have also owned but sold off a PA5 amp and another DAC. I never experienced a problem with any of these products.

It's like any low cost electronics - they are not going to last forever like an old school electronics component build with thru hole components, etc. This is the reality that one must confront in exchange for paying only a couple of hundred dollars for them!

There is always the luck factor) I had the Topping LA90 and a PA5, both broke down after a year....

 

[Talisman]

Makes sens but who says two mono blocks, says two PSU bricks, says I double the consumption and no time for the planet)
It remains ironic of course) But it would be cool to see a Stereo amp instead which would be much more affordable and rational

What changes if you have two power supplies that consume half as much or one that consumes twice as much?

 

[Talisman]

I can give some first hand testimony about Topping products. I own four DACs from them. I have also owned but sold off a PA5 amp and another DAC. I never experienced a problem with any of these products.

It's like any low cost electronics - they are not going to last forever like an old school electronics component build with thru hole components, etc. This is the reality that one must confront in exchange for paying only a couple of hundred dollars for them!

I guess we will then have to rely on your individual experience instead of a thread literally full of cases of topping product failures

 

[charlielaub]

The "dual mono" amplifier design attempts to completely separate each channel so that there is no crosstalk. For example, theoretically if both channels of a stereo amplifier share the same linear power supply, the current drawn by one channel appears as a slight sag in the rail voltage and this COULD slightly modulate the output of the other channel. In reality this does not happen. Firstly, this would require that the amplifier has very, very bad PSRR (power supply ripply rejection). Also, for class-D amplifiers the PS is typically regulated so that there is no appreciable effect on the voltage as current is drawn out of it.

The dual mono paradigm is no longer useful or needed.

 

[daniboun]

The "dual mono" amplifier design attempts to completely separate each channel so that there is no crosstalk. For example, theoretically if both channels of a stereo amplifier share the same linear power supply, the current drawn by one channel appears as a slight sag in the rail voltage and this COULD slightly modulate the output of the other channel. In reality this does not happen. Firstly, this would require that the amplifier has very, very bad PSRR (power supply ripply rejection). Also, for class-D amplifiers the PS is typically regulated so that there is no appreciable effect on the voltage as current is drawn out of it.

The dual mono paradigm is no longer useful or needed.

Agree )
Especially since TPA325X amps generally have an excellent PSRR, which is why the influence of the PSU is quite minimal on 3E Audio or Sylph Audio modules for example... Concerning the true definition of dual Mono amps, we agrees that each module should be powered by its own PSU. On the other hand, many Class D amps are labeled "dual Mono" when in reality two modules share the same PSU, it is questionable for the name)

 

[mike70]

Makes sense but who says two mono blocks, says two PSU bricks, says I double the consumption and no time for the planet)
It remains ironic of course) But it would be cool to see a Stereo amp instead which would be much more affordable and rational

I think your case is extreme .... class D amplifiers will not harm the planet, too low consumption and very few people buy amplifiers in the world.

Many cities in Europe are in electrical energy crisis by electric cars. That will do it.

 

[Guddu]

I think your case is extreme .... class D amplifiers will not harm the planet, too low consumption and very few people buy amplifiers in the world.

Many cities in Europe are in electrical energy crisis by electric cars. That will do it.

Lol... How about Class D amplifiers with Class A sound then!!! Someone sent this to me couple of days back:

 

[daniboun]

Lol... How about Class D amplifiers with Class A sound then!!! Someone send this to me couple of days back:


View attachment 358225

We can translate " Class D with bad Sinad" works too lol --)))

 

[Colonel7]

Where the mono amp can deliver it's full power is into 2 Ohm loads. You need more current in order to do this, so the FOUR amplifier blocks within the TPA3255 are arranged in a bridge-parallel configuration (a parallel connection of the two sets of bridged/BTL channels). There is nothing is to be gained if your speaker impedance is not dipping down that low. Hardly anyone will be able to take advantage of this extra power because home audio speakers rarely have such low impedance levels.

Something that can finally drive these wired in parallel?!

Home

Epique E150HE-44 5-1/2" DVC MMAG Extended Range Subwoofer 4 Ohm per Coil Epique E150HE-44 5-1/2" DVC MMAG Extended Range Subwoofer 4 Ohm per Coil Like. No. Other Combining world class performance with a reasonable cost, the Epique E150HE-44 5-1/2" carbon fiber cone woofer from Dayton Audio sets...

www.parts-express.com

 

[sejarzo]

I can give some first hand testimony about Topping products. I own four DACs from them. I have also owned but sold off a PA5 amp and another DAC. I never experienced a problem with any of these products.

It's like any low cost electronics - they are not going to last forever like an old school electronics component build with thru hole components, etc. This is the reality that one must confront in exchange for paying only a couple of hundred dollars for them!

I sold my D30 but still own both the D10 and E30.

It's the reliability issues that they have experienced with amplifiers that concerns me.

 

[charlielaub]

Something that can finally drive these wired in parallel?!

Home

Epique E150HE-44 5-1/2" DVC MMAG Extended Range Subwoofer 4 Ohm per Coil Epique E150HE-44 5-1/2" DVC MMAG Extended Range Subwoofer 4 Ohm per Coil Like. No. Other Combining world class performance with a reasonable cost, the Epique E150HE-44 5-1/2" carbon fiber cone woofer from Dayton Audio sets...

www.parts-express.com

Yes, when the VCs are in parallel the nominal impedance is 2 Ohms and the mono TPA3255 will deliver about 450W at clipping.

 

[charlielaub]

Lol... How about Class D amplifiers with Class A sound then!!! Someone sent this to me couple of days back:


View attachment 358225

Well, at least class-D gets rid of concerns about crossover distortion just like class-A but without its massive heat dissipation.

Of course there are new things to be worried about with class-D, but the best examples of the class do not seem to have many problems in the time or frequency domains...

 

[mike70]

Lol... How about Class D amplifiers with Class A sound then!!! Someone sent this to me couple of days back:


View attachment 358225

A spectacular example of marketing.
Take a positive "urban legend" and associate it to your product. Simple but effective in the "audiophile world".

 

[bennjude19]

Here's a preview of V3 mono internals and back photo.

 

[Sokel]

Lol... How about Class D amplifiers with Class A sound then!!! Someone sent this to me couple of days back:


View attachment 358225

That's not news,20 years ago my E-MU interface was advertised like that :





(now that I saw it,poor thing still holds it's specs) :