Fosi Audio V3 Mono Amplifier Review

[SMen]

Regarding a fosi pre-amp for these I'd like to see a balance pre with relays. A passive / active operation selector option, and dual volume controls to max out on the separation (in keeping with the monos). Dual volume gives channel balance and can be pretty useful in certain rooms and scenarios, and indeed old recordings.

But give a readout for each channel, for perfect center balance.

I appreciate I might be a bit of an 'outlier' on this last dual volume option, but been using this for years. You'd be surprised how often a balance tweak can help, and a good reason to combine with monoblocks.

 

[TraumaDisaster]

I don’t think that would work to run a separate amp per terminal. On a bi-ampable/bi-wireable speaker, yes, you could run two. But I don’t imagine there are a lot of speakers out there that would even need that level of power. Do you have a specific set of speakers in mind?

-Ed

"I don't think that would work." meaning it could break something? I did try it, I ran avr preouts rca from the left amp 1; and the right to amp 2. Then from amp 1 speaker wire that is premade as a biwire so it has 4 outputs and I connected it to a speaker that has bookshelf and atmos module so basically 2 speakers. I did that for the two left speakers and amp 2 for the two right speakers. The fosi handles the strain of two speakers fine for me. I crank those suckers up and with the atmos playing stereo it really fills the room for me.

 

[EddNog]

"I don't think that would work." meaning it could break something? I did try it, I ran avr preouts rca from the left amp 1; and the right to amp 2. Then from amp 1 speaker wire that is premade as a biwire so it has 4 outputs and I connected it to a speaker that has bookshelf and atmos module so basically 2 speakers. I did that for the two left speakers and amp 2 for the two right speakers. The fosi handles the strain of two speakers fine for me. I crank those suckers up and with the atmos playing stereo it really fills the room for me.

Well that answers that, then.

-Ed

 

[Roger285]

There's already 1 of those coming out like every other week.

Just like with the monoblocs, I'm hoping for something different, something that usually costs too much because it is a niche product. But when you can make them perform great at a very affordable price, it becomes a hit.

Monoblocs are nothing new, but with the V3 mono, everyone can afford it, and many want it. It would be awesome if they could do the same with a balanced pre amp. Not another dac that can also do a bit of pre amping.

2 balanced ins, 2 or 3 SE ins, nice buttons and volume control.

Currently many use their dac as a pre-amp, because it's not worth spending 800, 1100 for a dedicated pre. But a good dedicated pre makes controlling your audio so much nicer.

You might be interested in one of these. The Big Knob is completely passive, has 2 balanced inputs and 2 balanced out (or one balanced and one unbalanced) and is built like a tank. I've used them in my studio for years.

https://www.bhphotovideo.com/c/product/1313074-REG/mackie_big_knob_passive_studio.html/?ap=y&ap=y&smp=y&smp=y&lsft=BI%3A6879&gad_source=1&gclid=CjwKCAjwxLKxBhA7EiwAXO0R0JPz41GECgOB2D7WrYIixVYnW5Zh34riKPT9KpH1fXqRKfA43di6txoCjqIQAvD_BwE

 

[antcollinet]

"I don't think that would work." meaning it could break something? I did try it, I ran avr preouts rca from the left amp 1; and the right to amp 2. Then from amp 1 speaker wire that is premade as a biwire so it has 4 outputs and I connected it to a speaker that has bookshelf and atmos module so basically 2 speakers. I did that for the two left speakers and amp 2 for the two right speakers. The fosi handles the strain of two speakers fine for me. I crank those suckers up and with the atmos playing stereo it really fills the room for me.

That's not quite what you described in your previous post - where it sounded like you were connecting one amp to the lh terminals of a speaker, and a second amp to the rh terminals of the same speaker.

What you are doing here is connecting two speakers in parallel (main and atmos) into one amp. That will work at low levels, but with two speakers connected in paralell, you'll be halving the impedance. So 2x8ohm speakers will combine to be 4ohm - this will be fine. But 2x4ohm speakers will combine to be 2ohm, and the amp will struggle with this at higher volume settings.

 

[Sputnik]

You might be interested in one of these. The Big Knob is completely passive, has 2 balanced inputs and 2 balanced out (or one balanced and one unbalanced) and is built like a tank. I've used them in my studio for years.

https://www.bhphotovideo.com/c/product/1313074-REG/mackie_big_knob_passive_studio.html/?ap=y&ap=y&smp=y&smp=y&lsft=BI%3A6879&gad_source=1&gclid=CjwKCAjwxLKxBhA7EiwAXO0R0JPz41GECgOB2D7WrYIixVYnW5Zh34riKPT9KpH1fXqRKfA43di6txoCjqIQAvD_BwE

Thanks, the Big Knob is nice for a desk, not so much for a (or my) living room. But it does show that it doesn't have to cost an arm and a leg.

 

[gwing]

Thanks, the Big Knob is nice for a desk, not so much for a (or my) living room. But it does show that it doesn't have to cost an arm and a leg.

Also, just two inputs doesn't cut it (for me).

 

[EddNog]

Also, just two inputs doesn't cut it (for me).

There a lot of these devices on the market; the problem they have is a lack of remote control.

-Ed

 

[Joe Smith]

I like a balance control rather than separate volume pots for each channel, but can live with either. I do hope that both the Chinese manufacturers and Schiit both continue to make solid state preamps for those of us who use RCA inputs and have no pressing need for balanced ones...

 

[Lednek]

I am one of those who always rants and asks for high pass filters and sub output and master Vol control and all that - integrated in cheap amps -

But a separate preamp, balanced, with bass management under 1000$ as mentioned here, well, this is minidsp flex territory, very hard to beat IMO.

I guess I was hung up on the idea that I already have a good DAC and need to use it.
The MiniDSP Flex would be an all in one solution, even if the DAC section measures slightly lower than What I have, it us likely to be better than running the signal from my DAC through an additional processor. Is that the Gist of it?

 

[gasolin75]

 

[jvdburgt]

So, no one interested if the SP601 is an attractive option?

 

[DavidM1]

Nice review. Although some talk about how cool it would be to have meters or a preamp with phono inputs for an integrated amp that doesn’t appeal to me.

A simple power amp that pairs well with balanced outs from a good dac or dac/ streamer pretty much nails it for me. The auto on/ off is a bonus and the power bricks are a slight drag. However, matching excellent test results with a good price is the most important thing and Fosi seems to have hit the target.

 

[fredreadrick]

Good day!

 

[AndyLu]

ABX Audiophiles. Not my cup of tea. But I add it here for completeness. Not a bad review (if you can call it that) based only on subjective opinions. Make of it what you want:

 

[rgruber]

ABX Audiophiles. Not my cup of tea. But I add it here for completeness. Not a bad review (if you can call it that) based only on subjective opinions. Make of it what you want:

I like his series on building open baffle speakers but this review seems based on his preconceived notions and phoned in. Like he had to do it because everyone else has one up but he didn’t really want to and didn’t put much effort into it.

 

[iLoveCats]

ABX Audiophiles. Not my cup of tea. But I add it here for completeness. Not a bad review (if you can call it that) based only on subjective opinions. Make of it what you want:

He's got a point, the balanced in on these budget amps doesn't match up with what's out there for budget preamps. I agree, its good if you already have the preamp and just want the monoblock form factor. That's exactly what I'm doing. I have a Topping Pre90 and a D90 and I'm swapping these in for the form factor. The guy sounds exhausted honestly. Probably just tired of the neverending variations in these budget amps.

 

[Psinet]

For anyone wondering, these "10 amp" power supplies are actually just 6.25 amp (300W).

I googled the model number. So running 2 on the one power supply is less power than running two on 2x 48v 5A power supplies.

Williston Audio Labs just uploaded a video of him dyno testing them, and the power supply cannot provide enough power when split in two. He got higher numbers running a single mono on the "10A" (6.25A) power supply (370W at 1% distortion at 2 Ohm!!!!!).

 

[SMen]

For anyone wondering, these "10 amp" power supplies are actually just 6.25 amp (300W).

I googled the model number. So running 2 on the one power supply is less power than running two on 2x 48v 5A power supplies.

I think that this is the model number from an image - so I tried googling it too . Interesting!

HKA30048063-7D - the thing is that these say "48V 6.25A" on the units, while the Fosi variation is printed 10A(max) !

Did Williston Audio Labs actually give a power rating for the power supply in the video? I can only see the measurements through the amplifiers as you pointed out.

 

[Psinet]

I think that this is the model number from an image - so I tried googling it too . Interesting!

HKA30048063-7D - the thing is that these say "48V 6.25A" on the units, while the Fosi variation is printed 10A(max) !

Did Williston Audio Labs actually give a power rating for the power supply in the video? I can only see the measurements through the amplifiers as you pointed out.

Yes, they are nowhere NEAR 10A power supplies. Big D just repeats what the Fosi supplied ones say.

The model number where it says "48063" denotes it as a 48v 6.3A power supply. I would be surprised if it could reach 7 amp for more than a few milliseconds.