Streamer S3 Streamer Development Log

[will williams]

Hi Fosiphiles,

We’re thrilled to kick off this thread with exciting news: S3, Fosi Audio’s first-ever network streamer, is officially in development!

Inspired by your feedback and built for music lovers who crave high-quality streaming, the S3 aims to be the perfect digital bridge between your favorite services and your Hi-Fi system. Whether you’re using Wi-Fi, Ethernet, or Bluetooth, the S3 will keep your setup flexible and future-ready.

We’re planning support for Roon Ready, TIDAL Connect, Spotify Connect, AirPlay2, GOOGLECAST, and more — all in a compact design that complements the Fosi family.

In this thread, we’ll share key updates as development progresses: hardware design, app integration, certifications, and, of course, plenty of sneak peeks.

As always, we’d love to hear your thoughts, ideas, and suggestions. Let’s build the S3 together!

Here is the rendering sketch of the S3:


Basic Specs

Input:	WiFi/Ethernet, Optical, RCA, HDMI Earc with CEC, Bluetooth
Output	RCA, XLR, OPT, Sub-Out
Trigger	Out
In-Built DAC	AKM AK4493S
APP	Download the Fosi Audio app to connect and control the S3.

 

[Cbhere]

This is great news, I am in the process of making the same by combining your products with raspberry pi based streaming software. Will be great if your team can create the same, looking forward for your product release.

 

[miketxo]

Adding a color display and a USB out like the Wiim ultra

 

[Martin Roscos]

This looks absolutely spot on. And I love the design nod to the ZD3. Excellent work

 

[will williams]

Adding a color display and a USB out like the Wiim ultra

Hi

Sorry, the S3 does not support a display at the moment. I plan to add this feature in the next-generation product.

 

[will williams]

This looks absolutely spot on. And I love the design nod to the ZD3. Excellent work

Hi Martin,

Thank you for your recognition. When we gathered feedback from everyone about the streamer, many people mentioned this point. So it’s clear that this is something we absolutely need to deliver.

​

 

[will williams]

This is great news, I am in the process of making the same by combining your products with raspberry pi based streaming software. Will be great if your team can create the same, looking forward for your product release.

Hi,
Thank you for your anticipation — we won’t let you down! I’ll be posting regular updates here on the progress of the S3 development.

 

[troythector]

It would be amazing if this device/fosi app is capable of indexing your personal music collection stored on NAS shares on your LAN or USB. I currently use Volumio on Raspberry Pi but it is clunky and slow. This feature would also set the S3 apart from other streamers in the market.

 

[D1N0##]

To be a serious streamer it needs more than an optical digital output. Coaxial and USB too. Galvanic isolation on the digital outputs. If it has an internal power supply provide a way to bypass it for a linear DC ps.

 

[will williams]

It would be amazing if this device/fosi app is capable of indexing your personal music collection stored on NAS shares on your LAN or USB. I currently use Volumio on Raspberry Pi but it is clunky and slow. This feature would also set the S3 apart from other streamers in the market.

Hi,
"Could you please share which software or app you currently use to access your NAS music collection? For example, are you using DLNA/UPnP, SMB (Windows file share), NFS, or some other method?"

"When you mention USB, do you mean USB flash drives (thumb drives), external USB hard drives, or both?

 

[will williams]

To be a serious streamer it needs more than an optical digital output. Coaxial and USB too. Galvanic isolation on the digital outputs. If it has an internal power supply provide a way to bypass it for a linear DC ps.

Hi

Thank you very much for your suggestions

 

[will williams]

Hi all,

Here is the current development progress of the S3:
1. The initial PCBA design has been completed, and we are now tuning the sound.
2. The enclosure mold is currently in production (for now, we are using a 3D-printed enclosure for prototyping )

Paired with our new powered subwoofer, it sounds amazing — haha!"

 

[troythector]

Hi,
"Could you please share which software or app you currently use to access your NAS music collection? For example, are you using DLNA/UPnP, SMB (Windows file share), NFS, or some other method?"

"When you mention USB, do you mean USB flash drives (thumb drives), external USB hard drives, or both?

So for my NAS server I use TrueNAS Scale and have my media folder shared via SMB. For my audio player I use a Raspberry Pi 3B+ flashed with Volumio Audio Player in which I am able to add network drives via NFS or SMB. Volumio will then index your local music library from the attached network share and play your music via multiple output sources (i.e. HDMI or Raspberry DAC via HAT module).

USB support could handle external hard drives and flash drives for faster access to your local music library.

 

[slerch666]

Argghhh!
I JUST bought a WiiM to do this in my setup! If I knew this was on the way I'd have waited.

Will this also offer connection to Plex? I use Plex for streaming my personal music collection and it was a big reason I went with WiiM.

I could possibly be convinced to sell my WiiM or swap it out for this...

 

[will williams]

Argghhh!
I JUST bought a WiiM to do this in my setup! If I knew this was on the way I'd have waited.

Will this also offer connection to Plex? I use Plex for streaming my personal music collection and it was a big reason I went with WiiM.

I could possibly be convinced to sell my WiiM or swap it out for this...

Hi

It is not supported yet, but I don’t think this is an issue; it is already on our upgrade schedule, and we plan to roll it out gradually via OTA updates.

 

[SeeDee]

I agree with others that digital ports are a must as well as Plex support. So long as there is bit perfect transfers of data and all the things you've mentioned, you should be successful. I am excited and waiting... perhaps patiently, perhaps not.

 

[JVWGTR]

The one killer feature I'd love to see - that's hard to find - is analog pass-through for the RCA inputs. It would be perfect if I could connect my turntable without the signal being converted to digital and back to analog to pass through

 

[Memphiskat]

Since you are using a subwoofer with it, I assume it has a subwoofer output. But does it have a selectable crossover? Lowpass for the sub out and high pass for the main outputs? The high pass for the mains is must have to properly integrate the subwoofer in my opinion.

 

[troythector]

So for my NAS server I use TrueNAS Scale and have my media folder shared via SMB. For my audio player I use a Raspberry Pi 3B+ flashed with Volumio Audio Player in which I am able to add network drives via NFS or SMB. Volumio will then index your local music library from the attached network share and play your music via multiple output sources (i.e. HDMI or Raspberry DAC via HAT module).

USB support could handle external hard drives and flash drives for faster access to your local music library.

A change to my original suggestion, I did some research and found WiiM products have support Logitech Media Server (LMS), particularly the Pro and Pro Plus models, through the use of Squeezelite. If Fosi Audio could implement Squeezelite into the S3 Streamer, then this will be easier and provide a better use experience.

I have LyrionMusicServer (previously Logitech Media Server) as a docker on my UNRAID server and much prefer this option as I can use the "Music and Artist Information" plugin which gives additional information for my music collection: biographies, album reviews, credits, related artists etc. The information presented by this plugin are sourced from Wikipedia, Last.fm, Discogs and MusicBrainz and is very detailed.

I decided against using Volumio due to all the good features being hidden behind a paywall :-(

 

[will williams]

I agree with others that digital ports are a must as well as Plex support. So long as there is bit perfect transfers of data and all the things you've mentioned, you should be successful. I am excited and waiting... perhaps patiently, perhaps not.

Hi SeeDee,

Thank you so much for your support. Haha, whatever you guys suggest, we will make sure to do it.

Trust Fosi.

 

[will williams]

The one killer feature I'd love to see - that's hard to find - is analog pass-through for the RCA inputs. It would be perfect if I could connect my turntable without the signal being converted to digital and back to analog to pass through

Hi
Haha, I’m not sure how I should address you. We just had the weekend, so we didn’t get a chance to reply to your message in time.
I’m very happy that the S3 supports RCA input — this should meet your needs!”

 

[will williams]

Since you are using a subwoofer with it, I assume it has a subwoofer output. But does it have a selectable crossover? Lowpass for the sub out and high pass for the main outputs? The high pass for the mains is must have to properly integrate the subwoofer in my opinion.

Hi

Thank you for your suggestion.
Yes, for a subwoofer, the crossover is indeed a very important feature. We plan to gradually roll out these functions via OTA updates in the app.
Trust us — Fosi will never do anything that disappoints our users.

 

[Martin Roscos]

Hi,
"Could you please share which software or app you currently use to access your NAS music collection? For example, are you using DLNA/UPnP, SMB (Windows file share), NFS, or some other method?"

"When you mention USB, do you mean USB flash drives (thumb drives), external USB hard drives, or both?

I know nothing about the technicalities of any of this. I have a CD ripper that stores a ton of music that I would hope to connect. In my mind DLNA/UPnP means you just connect it and it works. I would hope it doesn’t need to get any more complicated than that. I could easily be wrong.
Plug and Play would be my desire!

 

[will williams]

I know nothing about the technicalities of any of this. I have a CD ripper that stores a ton of music that I would hope to connect. In my mind DLNA/UPnP means you just connect it and it works. I would hope it doesn’t need to get any more complicated than that. I could easily be wrong.
Plug and Play would be my desire!

Hi

Connecting the S3 is incredibly simple. We've always strived to make our products effortless to use—never a burden.

 

[will williams]

Hi Everyone,

Excited to share the latest updates on the S3:

1. The enclosure mold is completed, and the image shows the T0 prototype.
2. All interface functions and indicator lights are working properly.
3. App connectivity and streaming protocols (AirPlay 2, Spotify Connect) have been successfully tested.

Looking forward to the next milestone in our development journey!

 

[troythector]

Hi Everyone,

Excited to share the latest updates on the S3:

1. The enclosure mold is completed, and the image shows the T0 prototype.
2. All interface functions and indicator lights are working properly.
3. App connectivity and streaming protocols (AirPlay 2, Spotify Connect) have been successfully tested.

Looking forward to the next milestone in our development journey!

View attachment 1837View attachment 1838View attachment 1839

Thanks for the update Will. Is there a target release date you are able to share with us?

 

[will williams]

Thanks for the update Will. Is there a target release date you are able to share with us?

Hi,
I think it should be around October 2025.

 

[JVWGTR]

Hi
Haha, I’m not sure how I should address you. We just had the weekend, so we didn’t get a chance to reply to your message in time.
I’m very happy that the S3 supports RCA input — this should meet your needs!”

I saw the RCA inputs, does it convert the signal to digital? Or does it pass through as analog? I know the sound difference is probably negligible, but I hate the idea of plugging in a turntable only to have the sound converted to digital, as WIIM and others do

 

[troythector]

Hi,
I think it should be around October 2025.

Will the S3 also have Room Correction, PEQ and Subwoofer connection with HPF/LPF?

I will be adding the ZD3 into my signal chain but it does not have PEQ or bass management as far as I have seen, I could be wrong, if so please correct me.

 

[will williams]

I saw the RCA inputs, does it convert the signal to digital? Or does it pass through as analog? I know the sound difference is probably negligible, but I hate the idea of plugging in a turntable only to have the sound converted to digital, as WIIM and others do

Hi

Yes, it has RCA input.
But how the signal is converted depends on your settings.
You can choose RCA input with RCA output or RCA input with optical (OPT) output.

 

[will williams]

Will the S3 also have Room Correction, PEQ and Subwoofer connection with HPF/LPF?

I will be adding the ZD3 into my signal chain but it does not have PEQ or bass management as far as I have seen, I could be wrong, if so please correct me.

Hi

All of these features will be gradually added to the Fosi App via OTA updates. In particular, for room correction, our engineers have already released an initial test version, and we’re quite impressed with the results.

However, it will still take some time before the official release, as further optimization is needed.

 

[joostdh]

I like what I’m reading about this S3. My two cents:

Room correction / PEQ
Great to hear room correction is on the timeline. I already wrote this on the Q8 page but since tasting the ease of use and value room correction adds, I would no longer choose for anything in my living room without it. At my desk I have an RME ADI-2 as dac/headphone amp and I love the ability to correct for different headphones.

AirPlay
This could repalce the Wiim Amp I have in the living room now. The lack of Airplay on newer Wiim products rules them out for future purchases for me.

Continue adding value
But where credit were it is dus: Wiim’s relentless updates via OTA firmware and to their app is second to none. Any company that keep adding value, especially after purchase, gets my respect. Sounds like you plan to do the same

View attachment 1838

Physical design
I hope you try to match the visual design you already have. The prototype seams slightly off. My suggestion:
• Same knob size as ZA3 (purple/orange)
• Same diameter used for ident of ZA3 switches as size for buttons (green)
• Same curve as on the ZA3 (orange)
• Vertical alignment with ZA3 (yellow)
(Though it is well possible that when you mock it up in 3D certain things don’t work, don’t take my suggestions as gospel).

 

[troythector]

I like what I’m reading about this S3. My two cents:

Room correction / PEQ
Great to hear room correction is on the timeline. I already wrote this on the Q8 page but since tasting the ease of use and value room correction adds, I would no longer choose for anything in my living room without it. At my desk I have an RME ADI-2 as dac/headphone amp and I love the ability to correct for different headphones.

AirPlay
This could repalce the Wiim Amp I have in the living room now. The lack of Airplay on newer Wiim products rules them out for future purchases for me.

Continue adding value
But where credit were it is dus: Wiim’s relentless updates via OTA firmware and to their app is second to none. Any company that keep adding value, especially after purchase, gets my respect. Sounds like you plan to do the same



Physical design
I hope you try to match the visual design you already have. The prototype seams slightly off. My suggestion:
• Same knob size as ZA3 (purple/orange)
• Same diameter used for ident of ZA3 switches as size for buttons (green)
• Same curve as on the ZA3 (orange)
• Vertical alignment with ZA3 (yellow)
(Though it is well possible that when you mock it up in 3D certain things don’t work, don’t take my suggestions as gospel).

View attachment 1840

I have to agree wrt to the design, something just feels a bit off for me, seeing it is suggested to be paired with the ZD3 and ZA3.

I much prefer the flush front panel with the rounded top and bottom corners of the ZD3 and ZA3. This device feels like Fosi Audio is copying the design language of the WiiM Amp or Vibelink. There are no Fosi products with a similar design, except maybe for the MC351 or K7 DAC.