Fosi Audio's First Dual-Mode Balanced Amplifier ZA3

[Hertel]

Estou desapontado com as classificações de saída dos monoblocos usados para me dar mais saída, caso contrário, Fosi, posso pagar metade pelo segundo amplificador? Sim, eu entendo, é apenas um canal balanceado por lado
A matemática simplesmente não bate, mesmo se eu usar o tijolo de 48 V que já possuo.
Ainda como uma atualização da minha v3, muito bem e parabéns por seguir na direção certa

But the official numbers already showed that there would not be a large gain in maximum power. I believe that the most rational expectation would be to have more electrical current when the speaker's impendance drops to close to 2ohms, as this can be a problem for a single power supply of just 5 amps. Another improvement would be better channel separation, but whether this is noticeable in the real world I don't know.

 

[TonyJZX]

yeah to me the very very minor increase in power as a monoblock is a waste of time and money

like 90w to 110w? who cares?

and so the whole idea of this as a monoblock as with the A07 max isnt worth it

i think most of us had expectations that it would double in power like a class a/b

as single amp, yes i like it, no problem but the whole advertising behind this sounds disingenuous

 

[alarum_78]

After I ran the audyssey setup my L/R Front were showing -2db. So setting the volume to max on the Fosi looks to be ideal. Have not had a chance to mess around with the trigger yet.

Solved the issue. Seems the trigger cable I have is a little sketchy ??? But with the cable fully plugged in bottomed out wouldn’t work. I unplugged it a little and all in well now.

 

[alarum_78]

After I ran the audyssey setup my L/R Front were showing -2db. So setting the volume to max on the Fosi looks to be ideal. Have not had a chance to mess around with the trigger yet.

Solved the issue. Seems the Fosi Wants a Stereo 3.5mm cable. One the postive 12v tip touchs the trigger jack the amp turns on it. When the ground part the barrel of the 3.5mm gets *grounded** the amp would power off.

 

[G-Can]

Solved the issue. Seems the Fosi Wants a Stereo 3.5mm cable. One the postive 12v tip touchs the trigger jack the amp turns on it. When the ground part the barrel of the 3.5mm gets *grounded** the amp would power off.

Awesome, thanks for the update.

Now just have to wait to actually buy one.

 

[JCarp]

yeah to me the very very minor increase in power as a monoblock is a waste of time and money

like 90w to 110w? who cares?

and so the whole idea of this as a monoblock as with the A07 max isnt worth it

i think most of us had expectations that it would double in power like a class a/b

as single amp, yes i like it, no problem but the whole advertising behind this sounds disingenuous

My thoughts exactly. It's not even on par with the a07 max either which is the sad part. 110w vs 166w. I was really expecting more and it's aggravating as I was going to purchase 11 of these if they were as advertised. Not now though.

 

[G-Can]

My thoughts exactly. It's not even on par with the a07 max either which is the sad part. 110w vs 166w. I was really expecting more and it's aggravating as I was going to purchase 11 of these if they were as advertised. Not now though.

11? What would be their use?

For me, za3 is only interesting because it has 12v trigger.
If there is anything else similar with trigger support, let me know.

 

[JCarp]

11? What would be their use?

For me, za3 is only interesting because it has 12v trigger.
If there is anything else similar with trigger support, let me know.

The majority would be used as monoblocks in our children's rooms, our bedroom, my office etc, and I wanted to possibly use a few for our home theater setup to compare to other amps.

 

[ampguy]

Interested in getting one, how long is the wait? Is the 48V vs the 32V worth it for low volumes? Can I get the 32V and swap it with my 48V from Fosi V3 which is used for very low volumes?

 

[Music1969]

Hi can anyone please post photo of the 48V power adapter?

I want to see if it has electrical safety marking on it, for my country

@Fosi Audio

 

[Guddu]

Hi can anyone please post photo of the 48V power adapter?

I want to see if it has electrical safety marking on it, for my country

@Fosi Audio

48v PSU has CE and FCC markings.

 

[Guddu]

48v PSU has CE and FCC markings.

View attachment 337283

 

[Music1969]

View attachment 337284

Thanks, unfortunately no SAA / RCM / C-tick for Australia

Is there alternative @Fosi Audio ?

 

[Joe Smith]

Interested in getting one, how long is the wait? Is the 48V vs the 32V worth it for low volumes? Can I get the 32V and swap it with my 48V from Fosi V3 which is used for very low volumes?

The 32v adapter is fine for a low to moderate volume level...at least for the V3...

 

[TikBLang]

For me, za3 is only interesting because it has 12v trigger.
If there is anything else similar with trigger support, let me know.

forgive my ignorance, what is the use of the 12v trigger in layman's terms?

 

[G-Can]

forgive my ignorance, what is the use of the 12v trigger in layman's terms?

My AVR can decode 11 channels but can only power 9. So I need power amp to power 2 speakers.
To turn on my power amp together with the receiver you would use 12v trigger output (connector that goes from receiver to Poweramp) who then sends 12volt to power amp to turn it on and other way around, to turn it off together with receiver.

 

[vicenzo_del_paris]

forgive my ignorance, what is the use of the 12v trigger in layman's terms?

Power on /off the za3 from another device instead of doing it manually.

 

[jooc]

Maybe it's been answered already in this thread and I haven't found it, but very basically:

What's the purpose of running these as monoblocks if the output power rating only goes up 10% or 20%? Shouldn't the power output almost double in bridge mode?

In other words: What's the advantage of buying two and running them in mono mode when the power output is essentially the same? Is this really only meant for people with 2 ohm speakers?

Edit: Also, I've read up of PFFB, but have yet to find a good description of how specifically it changes the sound of the amp. I fully see how it's a better design overall, but is it a technology a listener could get excited about vs a board designer?

Maybe Fosi or someone else could describe in layman's terms *why* you would want to upgrade to two PFFB amps ran in mono mode, from the perspective of a listener.

Edit II: I guess I should backtrack a bit, one of the best descriptions of 'why' for PFFB might come right from these bullet items in TI's whitepaper:

".. 5. Output Noise Output noise is almost cut in half for systems with PFFB implemented. The lower the noise floor, the better users will be able to hear the small details in the audio..."

".. 7. THD+N vs Power .. this curve is useful to see how the amplifier performs at lower powers that are critical for how the amplifier sounds at typical room volumes such as 1 W to 10 W. ... The lower power performance which is very critical to how an amplifier actually sounds to a human ear is improved by roughly 5 dB with this PFFB configuration....


So from this am I to assume that you could potentially hear more detail at very low volumes, as you might be using it in near-field?

.

 

[jooc]

I thought it was some kind of mono stereo source button. Really strange to have a bridge button on the front.

The bridge button on the front is to call additional attention to the fact that it's bridgeable - it's a marketing decision, it's obvious, you don't need to read the tech specs to notice that feature. In the all-out war these guys seem to be having with Aiyima and others, every little marketing advantage is probably needed.

 

[Middle Earth]

Fosi is coming out with true monoblocks
Inexpensive Class D power wars