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Fosi Audio V3 Mono Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 13 2.0%
  • 2. Not terrible (postman panther)

    Votes: 20 3.1%
  • 3. Fine (happy panther)

    Votes: 123 19.2%
  • 4. Great (golfing panther)

    Votes: 483 75.6%

  • Total voters
    639
Are there any good reasons to put a DAC in between a Wiim Ultra and a pair of Fosi V3 monoblocks? I have an extra DL200, for instance.
None at all with one minor exception:

In the unlikely event you were to experience audible ground loop noise picked up between the Ultra and the amps, then an improvement might be achieved using your DAC with an optical connection between the Ultra and the DAC, which would eliminate ground loops between Ultra and Amp.
 
Are there any good reasons to put a DAC in between a Wiim Ultra and a pair of Fosi V3 monoblocks? I have an extra DL200, for instance.
Yes, so you can use XLR. (which got way lower thd on v3 mono)
 
Yes, so you can use XLR. (which got way lower thd on v3 mono)
Again - only beneficial if experiencing audible ground noise without the XLR.

(which got way lower thd on v3 mono)

Just the standard and expected 6dB resulting from the lower voltage/higher gain. Still inaudible.
 
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Are there any good reasons to put a DAC in between a Wiim Ultra and a pair of Fosi V3 monoblocks? I have an extra DL200, for instance.
https://archimago.blogspot.com/2024/08/part-ii-fosi-audio-v3-mono-amp-class-d.html
Check out this review with measurements and listening for any benefits to the balanced option your DL200 might bring.
Given you have both options you could try both and give feedback here, or on the user impressions thread. Part 1 of this article is interesting too, and compliment the review (I think) by Amir.
 
If I were to do that (add a DAC like the DL100) for the dB gain or hum, with the Wiim DAC managing the subwoofer, do I potentially introduce 'timing' issues?
 
If I were to do that (add a DAC like the DL100) for the dB gain or hum, with the Wiim DAC managing the subwoofer, do I potentially introduce 'timing' issues?
no and you could also adjust sub timing within the wiim app btw
 
If I were to do that (add a DAC like the DL100) for the dB gain or hum, with the Wiim DAC managing the subwoofer, do I potentially introduce 'timing' issues?
Try it and see ...
I've a pair of subwoofers which have line level volume and cut off adjustment as well as speaker level. I often have found integration easier with the speaker level inputs - but that is with adjustment by ear, where you try and get them to the level where they (the subwoofer(s)) are just detectable.
At the moment I have them connected via the line level inputs from a volume passive pre-amp which also has balanced outs.

I'm not sure theoretical views on this are the answer. I think you are in the position where you might try it and advise on your use case for others.

Post edit: and actually seeing @ninetylol 's reply above - this is a very good point ... kind of giving me an excuse to think of a wiim too!
 
I will definitely test and report.

The line out tests around 88dB Sinad in the pro, I assume it's the same or better here.
 
Balanced, i.e XLR and TRS, are normaly converted to single ended within the amp, because it is supposed to help with problems (screening) concerning long cable length (screening against induced electrical disturbances).
There are very few amps, which carry and amplify the input signal balanced (symmetrical) throughout the gain stages. The opinions on this are divided, if this will be an advantage or not. To avoid XLR or TRS, because a balanced input signal is transformed within the amp into single ended is thus quite "strange" and probably a misunderstanding of the reasons, why this is been used... :)
 
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Balanced, i.e XLR and TRS, are normaly converted to single ended within the amp, because it is supposed to cure problems (screening) with long cable length.
In a domestic setting it's mostly about avoiding possible ground noise issues. Common mode interference rejection is an added bonus, but rarely needed in domestic settings.
 
Are there any good reasons to put a DAC in between a Wiim Ultra and a pair of Fosi V3 monoblocks? I have an extra DL200, for instance.

Yes.

Not for sound quality but maybe for other features the specific DAC might provide e.g. possibly a physical volume control or extra inputs or a good headphone amp etc.
 
More like 13-14dB at the same voltage and different,highest gain (Arch also measures XLR with 2V output,so it's easy to compare)
I was referring to Amir's measurement here. It has yet to be explained why Archimagos measurements for RCA are so much worse than XLR, compared to Amir's results.
 
So did some testing and the one way Dc filter has stopped the feedback from one amp to another with just buying the one female splitter to two males and one single male to male. Hopefully the diagram shows how the DC stops the feed back from crossing over Compared to the original supplied spliter by Fosi.
This method has eliminated MY feed back noise at a cost of about £8.50 DC supply cable, male to male 5.5*2.5mm 2.5mm. Second cable splitter 5.5x2.5mm 1 female to 2 male 5.5mmx2.5mm DC Y splitter £6.88.
Total expense £15.00 or U$20.00
Cheaper than running two DC filters and two psu bricks!
Feel free to report if this helped.
Your welcome.
 

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I was referring to Amir's measurement here. It has yet to be explained why Archimagos measurements for RCA are so much worse than XLR, compared to Amir's results.
Actually are not very different,is just at different levels.
And the THD+N vs level chart shows a very steep curve even in XRL input which is 100dB SINAD at 4-5V but only 90dB at 2V or so (should be around 95-96dB in a very linear device)


1725479079941.png
 
So did some testing and the one way Dc filter has stopped the feedback from one amp to another with just buying the one female splitter to two males and one single male to male. Hopefully the diagram shows how the DC stops the feed back from crossing over Compared to the original supplied spliter by Fosi.
This method has eliminated MY feed back noise at a cost of about £8.50 DC supply cable, male to male 5.5*2.5mm 2.5mm. Second cable splitter 5.5x2.5mm 1 female to 2 male 5.5mmx2.5mm DC Y splitter £6.88.
Total expense £15.00 or U$20.00
Cheaper than running two DC filters and two psu bricks!
Feel free to report if this helped.
Your welcome.
I did not really understand your post.
But neither did I understand Fosi packaging another split cable with the DC filter they sent to me later so I have two split cables!

I am using one of the split cables to supply the other! If that is understandable. So I have one loose, unconnected split cable!

I was thinking about getting a junction connector and I am wondering if that is the male to male 5.5*2.5mm 2.5mm you are talking about? Then I could just connect to one split cable.

All very confusing!!
 
So anyone here "upgraded" from a WiiM Amp to these Monoblocks? From what Ive seen you get a bit more SNR and about 2db more max volume with the V3 Monos. On the other hand the Wiim Amp got better multitone and better intermodulation and ofc dsp more connections and a sub out.

While 200W on paper sounds great its really not much of difference in total db against the 120W of the Wiim Amp.

Any opinions or experiences?
 
I did not really understand your post.
But neither did I understand Fosi packaging another split cable with the DC filter they sent to me later so I have two split cables!

I am using one of the split cables to supply the other! If that is understandable. So I have one loose, unconnected split cable!

I was thinking about getting a junction connector and I am wondering if that is the male to male 5.5*2.5mm 2.5mm you are talking about? Then I could just connect to one split cable.

All very confusing!!
The original issue from where I can see is the original splitter shares an equal DC path to both amplifiers.This is where the feed back noise bleeds into each path. The new splitter cable in my diagram shows the PSU supplys one amp direct, and the other via DC filter one way. This means any feedback will stop dead at the DC filter and separate any feedback noises from each amp.
Nothing wrong with DC filter or psu, it was always the original splitter cable that was the issue post DC filter!
I'll take separate pictures of each cable so you know what to buy. I'm sure someone can explain in detail what I have done more eloquently.
Or I could say I have split the DC path pre filter and post filter, where Fosi decided to split the DC path post filter together.
It's right in my head and it works.(Lol emoji)
 
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The original issue from where I can see is the original splitter shares an equal DC path to both amplifiers.This is where the feed back noise bleeds into each path. The new splitter cable in my diagram shows the PSU supplys one amp direct, and the other via DC filter one way. This means any feedback will stop dead at the DC filter and separate any feedback noises from each amp.
Nothing wrong with DC filter or psu, it was always the original splitter cable that was the issue post DC filter!
I'll take separate pictures of each cable so you know what to buy. I'm sure someone can explain in detail what I have done more eloquently.
Or I could say I have split the DC path pre filter and post filter, where Fosi decided to split the DC path post filter together.
It's right in my head and it works.(Lol emoji)
:D I have two splitter cables thanks to Fosi ... But if I understand you correctly, we could junk the DC filter and just have a better splitter cable.
So the problem was with the splitter cable? Thank heavens they sound good despite all this (the V3 monos)!
 
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