Fosi Audio V3 Mono Amplifier Review

[amix]

Yeah, but to be fair Fosi aren't exactly too far off. Some nicer cases

Especially since the cases are already pretty decent.

 

[Kuuntelija]

I have the Sabaj a30a. Do you think that two of this Fosi v3 monos could be a better option with a good dac?

 

[Ze Frog]

Especially since the cases are already pretty decent.

They are, but if they could find a more static type design like WIIM have etc, would kind of carry the brand heritage along easier by being more instantly recognizable. Fosi is definitely at the stage now they would benefit from setting a brand image looks wise to differentiate from other similar sized amplifiers. Bit like how successful car manafacturers like BMW have specific design traits that are instantly recognizable.

 

[amix]

like WIIM have etc,

True. That WiiM is a hell of an offer. Only thing missing is load stability.

I just discovered a major turn off (attention, could be a pun) with this amp: the auto turn off:

Auto Standby Mode
High Energy Efficiency

I like to keep the PA on at all times. Sounds better to my ears.

 

[Ze Frog]

True. That WiiM is a hell of an offer. Only thing missing is load stability.

I just discovered a major turn off (attention, could be a pun) with this amp: the auto turn off:

Auto Standby Mode
High Energy Efficiency

I like to keep the PA on at all times. Sounds better to my ears.

Yeah, will be interesting to see how well implemented it is. Done right it shouldn't be bother, to me at least.

 

[sikahr]

True. That WiiM is a hell of an offer. Only thing missing is load stability.

I just discovered a major turn off (attention, could be a pun) with this amp: the auto turn off:

Auto Standby Mode
High Energy Efficiency

I like to keep the PA on at all times. Sounds better to my ears.

Switch says off/auto/on so keep it on on and you are golden

 

[quocheiser]

This V3 mono looks very juicy to do a four (4) amp bi-amping setup with.

I've asked Fosi via their forum if they can make it possible for the Kickstarter campaign buyers to add extra power supplies.

FWIW, I prefer to over-spec my power whenever possible (within monetary reason). Should get more life out of the power supply, less heat, and if lucky some added bonuses of extra headroom or decreased THD.

Would be great to if an online reviewer measures the V3 mono with the 48v/10a power supply to see if there is an improvement to THD similar to what the 3E module showed, as shared by @daniboun here: https://audiosciencereview.com/foru...o-v3-mono-amplifier-review.53474/post-1933697

 

[Ze Frog]

This V3 mono looks very juicy to do a four (4) amp bi-amping setup with.

I've asked Fosi via their forum if they can make it possible for the Kickstarter campaign buyers to add extra power supplies.

FWIW, I prefer to over-spec my power whenever possible (within monetary reason). Should get more life out of the power supply, less heat, and if lucky some added bonuses of extra headroom or decreased THD.

Would be great to if an online reviewer measures the V3 mono with the 48v/10a power supply to see if there is an improvement to THD similar to what the 3E module showed, as shared by @daniboun here: https://audiosciencereview.com/foru...o-v3-mono-amplifier-review.53474/post-1933697

Agree, they should definitely release the 10amp power supplies even if on their own so people can go that route. Probably not needed, but still, I'm of the same mindset of better to be overkill than just enough.

 

[staticV3]

Agree, they should definitely release the 10amp power supplies even if on their own so people can go that route. Probably not needed, but still, I'm of the same mindset of better to be overkill than just enough.

The 10A power supply is already available standalone:

Fosi Audio 48V Power Supply Adapter for TB10D, BT20A PRO,V3

Power your audio devices with the Fosi Audio 48V 5A Power Supply Adapter. Perfect for TB10D, BT20A PRO, V3 models. Get powerful sound instantly.

fosiaudio.com

 

[Ze Frog]

The 10A power supply is already available standalone:

Fosi Audio 48V Power Supply Adapter for TB10D, BT20A PRO,V3

Power your audio devices with the Fosi Audio 48V 5A Power Supply Adapter. Perfect for TB10D, BT20A PRO, V3 models. Get powerful sound instantly.

fosiaudio.com

Nice. I'm in UK and didn't spot that, although the 5 amp is available on Amazon.

 

[totti1965]

The amp torture testing has yet to begin/be done and so don't get too far ahead of yourself here. There is a reason Hypex and Purifi are more money and bigger.

Well, the Distortion at 4 Ohm 15 kHz Signal 1 Watt or 5 Watts is about minus 56 dB. The Audiophonics HPA S-400 ET is below minus 80 dB! You pay the extra EUR 1.500,-- for the not so shrill 15 kHz Tones.
Sarcasm

 

[Doodski]

Well, the Distortion at 4 Ohm 15 kHz Signal 1 Watt or 5 Watts is about minus 56 dB. The Audiophonics HPA S-400 ET is below minus 80 dB! You pay the extra EUR 1.500,-- for the not so shrill 15 kHz Tones.
Sarcasm

I don't follow these toy amps so I have no idea what you are saying.

 

[tomtoo]

I don't follow these toy amps so I have no idea what you are saying.

More than 350W at 2 ohms toys?? What killer amps do you have?

 

[Doodski]

More than 350W at 2 ohms toys?? What killer amps do you have?

We'll see how they do after they have been on the market and run hard and put away wet. That's 2 Ohms for a blip of a second. Not continuous. They cannot be compared to a full size class D amp with low impedance drive and thermal stability to match.

 

[tomtoo]

We'll see how they do after they have been on the market and run hard and put away wet. That's 2 Ohms for a blip of a second. Not continuous. They cannot be compared to a full size class D amp with low impedance drive and thermal stability to match.

Hehe if you would know me you would know that i question the long term thermal stability also. Buuuut at least the amp should behave in peaks very well even with demanding load. So talking about toys? What are your amps?

 

[Doodski]

Hehe if you would know me you would know that i question the long term thermal stability also. Buuuut at least the amp should behave in peaks very well even with demanding load. So talking about toys? What are your amps?

My amps are not your concern.

 

[tomtoo]

My amps are not your concern.

Ok, you can call toys what ever you want.

 

[EddNog]

Out of curiosity, I noticed it has two swappable op-amps...is one for the XLR input and one for the signal stage, or are both for the signal stage (due to PFFB design)? The ZA3 has one signal stage op-amp per channel, so two since it's a stereo amp, and then a single separate op-amp for the XLR input, and then two more for the subwoofer output. It makes sense that the subwoofer ones are out of the equation, but I just wanted to confirm exactly what the two swappable op-amps are actually for. I want to bring over the op-amps from my current ZA3s to the new V3 Monos when I get them, but I'd hate to have to order an extra pair of op-amps in the event the V3 Mono needs two op-amps just for the signal stage. I am currently running just 1 Burson V7 Vivid op-amp per ZA3 on the right channel only (leaving the left channel one stock), and am really hoping that I would not need to order 2 more to use the ones I currently have in the new V3 Monos.

I also went ahead and ordered a pair of the 10amp, 48volt power supplies from Fosi. I am currently running a pair of 5amp power supplies with my two ZA3s, but when I ordered them, I ordered them without any power supplies, so I will just include these 5amp ones with them when I sell them (after putting the stock op-amps back in).

-Ed

 

[GiBo61]

I have the Sabaj a30a. Do you think that two of this Fosi v3 monos could be a better option with a good dac?

I also have a Sabaj A30a and I'm really happy about it. I guess the performance will be similar but with more boxes and cables around. Furthermore the Sabaj has a sub out with high pass and low pass filters plus tone controls.

 

[DavidM1]

Yeah, but to be fair Fosi aren't exactly too far off. Some nicer cases and inbuilt power supply as you say and they are pretty much there.

As for the toggle switches, kind of like them myself, like a switch to have an old school kind of quality. Best switchgear ever that I have experienced is the Denon PMA 110. That thing is so mechanically satisfying. I'll probably purchase one at some point on that fact alone.

I know knob feel is a big thing in hifi (yes, I wrote that) but it hadn’t crossed my mind that these switches were a problem. Kinda old-school now that I think about it.