Could someone please explain how Fosi amps work?

[Iggy]

Hi all,

Im still relatively new to this and currently running a WiiM Amp through Wharfedale Diamond 12.2’s and quite happy with it.

However I’m thinking of upgrading the speakers to maybe the Dali Oberon 5, and that’s started me thinking about doing the same with the source as well.

I’ve started reading about these Fosi Amps and how you can put two together (if I’ve understood correctly) and maybe getting a couple of these and WiiM Pro Plus or Ultra to feed some better speakers?

Would something like this be an improvement over the WiiM Amp or not?

There are so many Fosi models V3, ZA3, BT20…..and do you need one or two? From what I can see you can wire up two together, I assume one for each speaker, but does that mean you lose stereo imaging?

I’m old and confused, if someone could take pity on me and offer some clarity I’d really appreciate it

Thank you.

 

[Trekkis]

If you want to improve sound you should first of all consider better dac. Wiims have relative poor dacs. Dac is the real source of sound. So better dac and wiim ultra is far superior than wiim amp. As wiim amp can not use external dac - this is this model worst limitation.

Regarding fosi, if you use use two (in mono mode), result would be slightly better sound, slightly better stereo imaging and more power - so better dynamic in case of speakers with low sensitivity. But this is not so important in most cases as dac, or even used opamos. In fosi amp you can replace internal components - op amps - for better ones. Dac and op amps are far more important than mono mode.

Mono mode (pair) is not needed in case of better quality speakers, is needed only for high volumes and low sensitivity speakers.

For better quality speakers better dac is needed.

Only za3 and two times cheaper but basically the same aiyima 07 max can be used switchable as mono or stereo. V3 and others ale stereo only. There is separate v3 mono - this one is mono only. Can work only as pair.

Once again - in case of mono mode you would not lose stereo imaging, you would have little better. Each mono block is simply working independently for left and right channel, but from the same source - so power and separation are better. all other remain the same.

In case of such amps, used power adapter is important. There are different power supply with different voltage. Better power adapter with higher voltage results more power.

 

[Iggy]

Thanks for your reply….so to get a better sound with better speakers, I would need….

WiiM Ultra
Fosi x 2 (Za3 or V3?) in mono mode with one amp to the left speaker and the other to the right speaker?

Is that correct?

If I’ve got the above right, which Fosi do I connect the WiiM Ultra to in order to get a stereo output?

Why is this all so complicated

 

[Doublej]

You can easily go down the audiophile rabbit hole spending upwards of $100K per component if you have the funds and the desire. Sine you are quite happy with your speakers I would recommend adding a active subwoofer ($~300-$500 if you are in the US) to your existing setup.

Here's why from a publication that caters to those folks spending mega bucks on systems:

Adding an actively powered subwoofer can greatly increase your system’s dynamic range, bass extension, midrange clarity, and ability to play louder without strain. The additional amplifier power and low-frequency driver allow the system to reproduce musical peaks at higher levels. Moreover, removing low frequencies from the signal driving the main loudspeakers lets them play louder because they don’t have to reproduce low frequencies. The midrange often becomes clearer because the woofer cone isn’t furiously moving back and forth, trying to reproduce low bass. This improvement in a small speaker’s performance can be dramatic. The small woofer’s excursion is no longer a limiting factor in how loudly the system will play when low frequencies are filtered from the signal driving it. The midrange is much cleaner, and the overall system sounds like a large, full-range speaker.

From the Absolute Sound, https://www.theabsolutesound.com/articles/subwoofer-basics/

 

[Trekkis]

As I said, there is no need for 2 fosi. One would be enough in most cases.

Main difference between za3 and v3 except option to work as mono or stereo are connections. Za3 and v3 mono have balacend connection. Original v3 has not. And za3 (and aiyima 07 max) has switchable mono / stereo modes. V3 / v3 mono are not switchable.

What is needed for better sound is better dac. Connected with even simple original v3 (stereo version) or cheaper 07 max.

Also post above is correct. Adding subwoofer can bring a lot more in practice. Fully true.