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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 13 1.8%
  • 2. Not terrible (postman panther)

    Votes: 23 3.2%
  • 3. Fine (happy panther)

    Votes: 139 19.4%
  • 4. Great (golfing panther)

    Votes: 540 75.5%

  • Total voters
    715
Likely a rookie question, but would I be able to use my subwoofer with two of these mono amps given my current gear?

Currently I have a Wiim Pro feeding optical into a Topping DX3 Pro+ DAC, which runs RCA into my Loxjie A40. My sub is fed with the sub-out RCA on the Loxjie.

By the time my two Fosi monos arrive, I'll have a Speedwoofer 10S MKII. The answer here is probably simple, but I can't figure out how to keep the sub in the picture unless I keep the Loxjie in the mix. Also important that I be able to keep the volume the same between the speakers and sub without having to match different volume controls for my bookshelves and sub.
That subwoofer's manual shows that is has multiple ways you can integrate it into the system. Your DX3's line level outputs can be used this way:
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Or if you choose to, you can use the speaker-level outputs from the V3 Monos instead doing this:
1714151198790.png


-Ed
 
My CD player…Yamaha CD-S303 has a built in DAC and turntable…Miracord 770H doesn’t need one…so would I even need one. I’m an old vintage guy and still wrapping my head around all this new black magic…lol.
A newer DAC will accept higher resolution source material, so that is up to you. Let's say down the line you purchase a network streamer and want to listen to high-resolution lossless music, a new DAC would support the higher resolution. Additionally, these new Chi-Fi DACs have ultra-high quality measurements, so...arguably may sound better than the DAC in your CD-S303 (I do not know for a fact that it will or not for CD-quality music as I have not seen test results/measurements for the DAC in that CD player).

-Ed
 
My CD player…Yamaha CD-S303 has a built in DAC and turntable…Miracord 770H doesn’t need one…so would I even need one. I’m an old vintage guy and still wrapping my head around all this new black magic…lol.
I have an SMSL C200 and can vouch for it being a fabulous unit. Anything similar and new from SMSL would likely be very good as they seem to have no end of well designed DACs. Perhaps find one with optical, co-ax and USB inputs and balanced (either TRS or XLR) outputs... and a remote control.

I would connect a streamer such as a WiiM mini to the optical input, a coax output from your CD player (RCA cable) if it has one to the co-ax input, your iPad or iPhone or computer to the USB input of the DAC, and send the balanced outputs from your DAC to the V3 monos’ balanced inputs. If your turntable doesn’t need a phono preamp I would connect it directly to the V3 monos’ RCA inputs. This would be a nice setup for listening to streaming music or playing vinyl. The co-ax connection to the CD player will likely be an upgrade for CDs and the USB connection would allow listening to hi-res files when you felt like it. The remote will let you power on and off, switch inputs and control the volume.

if you aren’t looking to stream music and only to play CDs and vinyl then, as you say, you don’t need a DAC. Use a preamp to collect the signals from CD player and turntable and send them to the V3 monos. Old school or old school plus streaming would be the first decision.
 
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Several different YouTube videos, reviewers, this site (Amira), and others.
I meant device upstream of your preamp (What feeds the pre - and if a DAC, what feeds that?)
 
haha, as expected Andrew Robinson aired another rant on small ch-amps wining they're comming too fast (instead 3 year market cycle xD) and mentioning v3 monos only in context of power supply problems (also he's lying they got to the market with this problem). What a dipshit.
 
Thank Amir so much for the measurement! The V3 Mono is another amplifier co-created with members, following the V3 stereo amp. We would particularly like to thank @Toku, @ModDIY , @mike70 , @cyclo, and all the other members who have provided us with invaluable suggestions.

The V3 Mono is our first amp with PFFB implementation. During the period we sent the set to Amir for testing, our R&D team did not stop optimizing the V3 Mono, and we have now further improved its frequency response curve. Below is the chart for your reference.
View attachment 360736


The V3 Mono is currently in production, and it will be launched on Kickstarter on the 20th of this month. There will be very attractive discounts available then, and we hope you'll stay tuned!:)


Question to throw out there for any to respond... Will my 57-year-old ear listening to via Wharfedale EVO 4.2 and hear the sound quality between something like these Fosi V3 monos as compared to Topping LA90
 
I meant device upstream of your preamp (What feeds the pre - and if a DAC, what feeds that?)
I have a Yamaha CD-303 CD player, a Miracord 770H turntable, an Audis Bluetooth receiver, and a XM radio receiver hooked to my receivers.
 
Thanks to all that has replied. Your suggestions has led me to think about equipment choices. I’m still thinking my original thoughts will work for me and my budget but I really like the idea of the SMSL C200 DAC and I’ll look into a streaming device later as the budget allows. Thank you again.
 
Question to throw out there for any to respond... Will my 57-year-old ear listening to via Wharfedale EVO 4.2 and hear the sound quality between something like these Fosi V3 monos as compared to Topping LA90
Most likely no. Unless your listening room is big and you are already a bit deaf and then need some extra watts :)
But then again if you are deaf you would not notice the extra distortion if you pushed the topping beyond its limits...
 
Question to throw out there for any to respond... Will my 57-year-old ear listening to via Wharfedale EVO 4.2 and hear the sound quality between something like these Fosi V3 monos as compared to Topping LA90
I would say that is pretty unlikely. 57 year old ears, or 20yo ears come to that.
 
It would be very interesting to see Fosi make a balanced pre-amp along the lines of the Schiit Freya/Kara, Gustard P26, ...
Precisely my thoughts. @Fosi Audio. The Schitt Kara is the closest thing I've found to a perfect preamplifier to pair with the V3 mono, but it has no bass management and is expensive. If you could check the same boxes as the Schitt Kara, with the addition of an adjustable low pass[40-120 hz) filter for the Sub outputs. And even more importantly, a simillar high pass filter for the speaker output, you would have something truly special, especially if it could be done at a much lower cost and still be profitable. I believe these monoblocks with such a pre-amp would completely change 2 channel stereo listening and bring it to many people who have been priced out of the hi-fi hobby.

If someone wiser than me can explain whi active bass management would not be a good idea in a pre-amp. I'm not set on it. It seems like an incredibly desirable feature providing it can be implemented without a deleterious effect on the sound quality.
 
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Precisely my thoughts. @Fosi Audio. The Schitt Kara is the closest thing I've found to a perfect preamplifier to pair with the V3 mono, but it has no bass management and is expensive. If you could check the same boxes as the Schitt Kara, with the addition of an adjustable low pass[20-100 hz) filter for the Sub outputs. And a simillar high pass filter for the speaker output, you would have something truly special, especially if it could be done at a much lower cost and still be profitable. I believe these monoblocks with such a pre-amp would completely change 2 channel stereo listening and bring it to many people who have been priced out of the hi-fi hobby.

If someone wiser than me can explain whi active bass management would not be a good idea in a pre-amp. I'm not set on it. It seems like an incredibly desirable feature providing it can be implemented without a deleterious effect on the sound quality.
There’s no reason not to include it other than cost so long as there is a bypass for people who don’t have a need/run a subwoofer. Although I would personally use that feature for sure. I eyed Emotiva BasX PT2 and Parasound NewClassic 200 preamps with bass management for a long time seriously considering buying one of them because of the bass management features but part of the reason I passed on them is a refusal to give up balanced interconnects.

Frankly if either of them had balanced inputs and outputs, I’d already have bought it. Unfortunately, neither of them do.

This is a good opportunity for Fosi for market-making for sure, a BALANCED preamp WITH bass management for a reasonable price would be truly killer and have basically zero competition anywhere at or under $1,000.

-Ed
 
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Personally, I could live without the bass management but a decent balanced pre-amp would be great. Pre-amps are way overpriced for what they are probably because they are geared toward a small, specialty market. I've considered the various Schitt models but honestly I kinda hate the name and all the juvenile wordplay that it induces among reviewers and the clicky volume control, stupid reasons but can't bring myself to buy one.
 
Personally, I could live without the bass management but a decent balanced pre-amp would be great. Pre-amps are way overpriced for what they are probably because they are geared toward a small, specialty market. I've considered the various Schitt models but honestly I kinda hate the name and all the juvenile wordplay that it induces among reviewers and the clicky volume control, stupid reasons but can't bring myself to buy one.
Ha. I also find the name unappealing. Names are important. Just ask Bentley or Ferrari.
 
There’s no reason not to include it
Preamps are (more often than not) pure analogue devices. Certainly all the shiit ones are.

Today bass management is typically and more effectively done with DSP digitally, either in the DAC, or in a digital to digital device upstream of the DAC.

It makes more sense to ask "why not put a proper preamp with variable gain, and analogue volume control into a DSP Dac?"
 
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 see they provided specs on the SP601 speakers. On paper they look quite good, anyone has an idea how they perform against well known speaker brands (like Monitor Audio)?
 
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I had never used kickstart, today I created an account to support this project.
Normally I don't like to put money forward but I want to help Fosi as a company and its policy of listening to users and collaborating.

Just a question. When creating the account I was not asked anything about the delivery address, how does it work?
No worry. We'll send you a survey to collect your delivery address when the campaign ends.:)
 
This is precisely the point of these. One per channel.

-Ed
I meant to say one amp to the Left terminal, a 2nd amp to the Right terminal of speaker A. Then use another 2 amps for speaker B. I'm new to this, would this be helpful to bring more power? This would be for speakers with one binding post, but I guess with dual binding post could you add 4 amps to ONE speaker to help bring more power?
 
I meant to say one amp to the Left terminal, a 2nd amp to the Right terminal of speaker A. Then use another 2 amps for speaker B. I'm new to this, would this be helpful to bring more power? This would be for speakers with one binding post, but I guess with dual binding post could you add 4 amps to ONE speaker to help bring more power?
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
 
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