Fosi Audio V3 Mono Amplifier Review

[Cal_Cobra]

But where you can reed about thees aliexpress clones? Are there any trustworthy recommendations? Where? I need 1xlr and 3rca inputs - if cloned amp cost 500$ so cloned preamp should be easily around 200$ and that would be grate alternative for vintage preamps and non existing new reasonably priced preamps

I really like these two preamps. I did as much research as I possibly could on them before purchasing, and like you I was also looking for a mix of RCA and balanced XLR inputs, and outputs.

The silver E300 preamp on the top sounds fantastic, amazing even. I like having tone controls (perfect speakers or not) and this has bass, mid-range and treble controls. It has 3 RCA inputs and 1 balanced XLR input, and 2 each RCA outputs, and one balanced XLR output. Has a remote that controls input selection and volume. This model is also available with optional Bluetooth at the sacrifice of one set of RCA inputs. I personally opted not to get it as I have several Bluetooth capable devices and didn't want to add a potential source of noise to the preamplifier. This was about $413 delivered.

The gold Breeze Audio (aka BRZHiFi) is a replica of the Accuphase C245. It has 2 RCA inputs and 2 balanced XLR inputs, and one each RCA and balanced XLR outputs. Has a remote that controls volume. I like the large pale blue lit VU meters, a nice departure from the inexpensive little round amber VU meters that've flooded the market on all of the cheap Asian audio products. This was about $463 delivered.

Both preamps sound great, with a nod to the silver E300 for sounding just a bit better, and it also appears to have a higher preamp output level as it drives my amp much harder than the gold Accuphase C245 replica. Build quality is fantastic, both units are built like tanks, and quite heavy. All of the lettering on the face of the gold Accuphase C245 replica is laser etched (or CNC machined?), very nicely done.

As this is pretty far off topic, if you want to PM me, I'd be happy to answer further questions.

 

[Kayshot]

I picked up an SMSL D-6s (DAC with 2 rca outs, 2 balanced XLR outs).
I did this specifically so that I'd have something with volume control and balanced outs that I could then use with my V3 monos for 2-channel listening.

Seemed like a great idea, until I realized just now that I'll have no way to retain the room correction from my Denon X3700H, as this AVR doesn't have balance pre-outs!

Oh well, looks like I'll be using the RCA pre-outs on the Denon into the Mono V3's. The benefit of room-correction far outweighs the benefits of balanced vs unbalanced in my scenario.

 

[Rafaille]

I picked up an SMSL D-6s (DAC with 2 rca outs, 2 balanced XLR outs).
I did this specifically so that I'd have something with volume control and balanced outs that I could then use with my V3 monos for 2-channel listening.

Seemed like a great idea, until I realized just now that I'll have no way to retain the room correction from my Denon X3700H, as this AVR doesn't have balance pre-outs!

Oh well, looks like I'll be using the RCA pre-outs on the Denon into the Mono V3's. The benefit of room-correction far outweighs the benefits of balanced vs unbalanced in my scenario.

Or you could see this as an opportunity and embark on the journey to DSP and room correction

 

[fredreadrick]

They send a new gift , we can choose 2 Muses02 chip instead Hex Driver Wrench 4 Piece Set + the cables .

Which one you willchoose?

2 op amps.....

 

[antcollinet]

Oh well, looks like I'll be using the RCA pre-outs on the Denon into the Mono V3's

You can create a cable (not generally available to buy) (if you have moderate soldering skills or can find someone that does) that give you all the noise immunity benefits of a balanced output but from RCA, as shown here by @staticV3. (It only woks from unbalanced output to balanced input - not the other way)

Noise issue- single ended signal and different ground reference?

I have a troubling noise issue that I spent a fair bit of time diagnosing today. My amplifier (3e audio unit) is installed in my car, and is fed by a dc boost module to go from 12v to 48v. The amplifier is fed by a DSP, which runs on 12v. Because the DSP has single ended RCA outputs (not...

audiosciencereview.com

Probably only worth doing though if you experience ground noise from that connection, when using it as unbalanced.

 

[Matt F]

If anyone wants my Muses02 Chip and is based in UK I can send along for free as postage won't cost me much and I'm never going to use.

How much do you want? I’m interested

 

[Matt F]

I went with 2 op amps but we need 4 for stereo. The 2 op muses will likely end up in my BT20APRO if I can’t source 2 more.

 

[echt]

There is only one channel in a monoblock, as you may have realised.

Yes mono blocks are one channel but you run two sumultaneouly for stereo.

a. Fosi offers the unusual option of a shared 10A power supply via a spliiter cable. Independenttly testing to see how the shared 10A compares to the separate 5A power supplies would be of interest to some.

b. More importantly to me, if you only test a single channel, you won't know if beat frequencies are generated.

My follow up questions to Amir were intended to see if there was a way to test for beat frequencies or if he considered them non-issues and/or not worth the effort to test (if a test was possible).

 

[Down South]

Yes I lost money on a record cleaner project called VinylSonic. They never produced a product but collected over 600,000 dollars

This happens on Indiegogo - lost money on a no-show and on a crap product - caveat emptor.

 

[Sokel]

Measurements would be good. But no harm in those who don't want them to offload them.

I think visuals are more convincing sometimes:

I really-really wonder if any of Fosi's engineers had a look at the way this pic shows an op-amp change.
And I really-really hope friends here who will go to the despair or replacing the op-amps don't do it this way.

 

[Down South]

Some valid points about the benefit of mono amps have been raised. It would be good if Amir was to check out Rod Elliot's site. He's a no B/S Australian.

He destroys the b/s of bi-wiring - if you really want to improve the sound try his rec. not just bi-amping but use one amp for bass and another for mids and treble. It's the bass that uses most of the juice.

One other point - I paid for the hex set and a set of cables. Now it appears we get these for free. I'm not interested in the Muse o-amps but I would like to have the 3.5mm to RCAs. I've sent an email to Jocelyn to sort this out. Hs anyone else paid for what appears will now come for free?

 

[Lednek]

I picked up an SMSL D-6s (DAC with 2 rca outs, 2 balanced XLR outs).
I did this specifically so that I'd have something with volume control and balanced outs that I could then use with my V3 monos for 2-channel listening.

Seemed like a great idea, until I realized just now that I'll have no way to retain the room correction from my Denon X3700H, as this AVR doesn't have balance pre-outs!

Oh well, looks like I'll be using the RCA pre-outs on the Denon into the Mono V3's. The benefit of room-correction far outweighs the benefits of balanced vs unbalanced in my scenario.

I have asimilar setup and plan. Using a Dennon 3400. I'll be using the LCR single ended preout to drive 3 V3 mono for the front stage. Additionally the balanced output from the DAC can be used for a pure 2 channel experience. I Imagine I'll use the RCA pre-outs more often than not, as I like having the bass management and dual subs. The monos have plenty of power to drive my towers straight from the DAC. I am interested to hear it. And, Fosi is sending you cables anyway. Might as well give it a try and have both options available.

 

[Kayshot]

Or you could see this as an opportunity and embark on the journey to DSP and room correction

Oh I am! I've ran Audyssey before, but today I'm going to attempt sub alignment and EQ with REW and MiniDSP 2x4 HD. Wish me luck! Going to follow the video from Home Theater Guru.

 

[Trasam Audio]

Yes, several people replied to me and explained this. Including Amir himself. I finally know what "PreAmps" are for.
Always wondered what the purpose of this was and why you would need a volume control that goes into an amp when Amps have volume control.
I apologize for my ignorance because I only live in the headphone world. I have no powered speakers outside of powered monitors.

Yeah, why do you need a volume control when your amps already have volume control?

 

[redstang]

I went with 2 op amps but we need 4 for stereo. The 2 op muses will likely end up in my BT20APRO if I can’t source 2 more.

Well, you can just swap one of them in each, but you need to do both to make it more noticeable, I guess. I didn't know this and figured I'd get the two op amps since I got two amps and at least have something to try. But now if you really want to go whole hog you're in for another 50+ bucks for two more.

The cost of those Sparkos op amps destroys the value proposition for these (and really any other inexpensive) amps. The fact that you need 4 for the full effect is dumb since each pair of those cost more than the amp itself. Every reviewer I've ever watched always blathers on about how much better the Sparkos op amps are, so it makes me curious, yet suspicious. How is there no one that just outright states that they make no difference? Don't want to go off topic in this thread - anyone familiar with another thread on here that discusses op-amp rolling?

 

[EddNog]

Well, you can just swap one of them in each, but you need to do both to make it more noticeable, I guess. I didn't know this and figured I'd get the two op amps since I got two amps and at least have something to try. But now if you really want to go whole hog you're in for another 50+ bucks for two more.

The cost of those Sparkos op amps destroys the value proposition for these (and really any other inexpensive) amps. The fact that you need 4 for the full effect is dumb since each pair of those cost more than the amp itself. Every reviewer I've ever watched always blathers on about how much better the Sparkos op amps are, so it makes me curious, yet suspicious. How is there no one that just outright states that they make no difference? Don't want to go off topic in this thread - anyone familiar with another thread on here that discusses op-amp rolling?

People who insist they make no difference either won’t bother testing or attest that measurements show nothing. People who insist they do make a difference will tell you they hear it and what those differences are. Your options are either try to make measurements and search for your own objective answer or just, “trust your ears,” and listen for your subjective differences.

-Ed

 

[Nopiano]

Yes mono blocks are one channel but you run two sumultaneouly for stereo.

a. Fosi offers the unusual option of a shared 10A power supply via a spliiter cable. Independenttly testing to see how the shared 10A compares to the separate 5A power supplies would be of interest to some.

b. More importantly to me, if you only test a single channel, you won't know if beat frequencies are generated.

My follow up questions to Amir were intended to see if there was a way to test for beat frequencies or if he considered them non-issues and/or not worth the effort to test (if a test was possible).

Sure, and I see that you’re ideally seeking tests on a pair, as that’s how most of us will use them. Good idea about seeking a comparison between the split 10A -v- 2x5A because again that’s the decision most buyers face. (I chose the higher powered option on my v3)

 

[Guddu]

People who insist they make no difference either won’t bother testing or attest that measurements show nothing. People who insist they do make a difference will tell you they hear it and what those differences are. Your options are either try to make measurements and search for your own objective answer or just, “trust your ears,” and listen for your subjective differences.

-Ed

One can always agree to disagree.

 

[SMen]

One can always agree to disagree.

People who insist they make no difference either won’t bother testing or attest that measurements show nothing. People who insist they do make a difference will tell you they hear it and what those differences are. Your options are either try to make measurements and search for your own objective answer or just, “trust your ears,” and listen for your subjective differences.

-Ed

Yes, one can always agree to disagree. There are some who have tried, and some who have not, but have (strong) opinions based on measurement or theory.
But let people try if they want to and come to their own conclusions, but be self aware, especially if you have come to your own conclusions, having done the same...

I just don't get the half measures here with op amp 'mixes' in parallel. Anyway! Be safe etc. I think one needs 4 the same 2x2 really, in parallel.

 

[Guddu]

Yes, one can always agree to disagree. There are some who have tried, and some who have not, but have (strong) opinions based on measurement or theory.
But let people try if they want to and come to their own conclusions, but be self aware, especially if you have come to your own conclusions, having done the same...

I just don't get the half measures here with op amp 'mixes' in parallel. Anyway! Be safe etc. I think one needs 4 the same 2x2 really, in parallel.

I am in category of those who have tried, fried the brain to limit to find any difference.
But I am still hopeful….. may be one day