FOSI S3 Balanced Streamer Review

[amper42]

I see a lot of praise for XLR out on S3. I don't see prominent warnings about how unsafe it can be to connect a streamer like the S3 over XLR to an amp with no volume control like a Purifi or Hypex model. These amps tend to offer the quality many audio users look for and many of us own them.

Possible issues using XLR out on S3 direct with Purifi/Hypex amps is not insignificant:
1. Lack of visual feedback: There is no volume display on S3.
2. Danger lies in potential software or hardware glitches that could reset the volume to 100% (fixed output), potentially damaging speakers or hearing.
3. S3 balanced XLR outputs connected directly to a high-gain power amp is risky, even with only a small digital volume error.

If you try to correct possible safety issues by adding a downstream volume control it increases cost and may also add distortion to the audio chain. If you weigh speaker safety concerns, the S3 XLR outs may actually not be all that useful. Immature software simply adds to the risk.

 

[TheLavenderBaron]

I see a lot of praise for XLR out on S3. I don't see prominent warnings about how unsafe it can be to connect a streamer like the S3 over XLR to an amp with no volume control like a Purifi or Hypex model. These amps tend to offer the quality many audio users look for and many of us own them.

Possible issues using XLR out on S3 direct with Purifi/Hypex amps is not insignificant:
1. Lack of visual feedback: There is no volume display on S3.
2. Danger lies in potential software or hardware glitches that could reset the volume to 100% (fixed output), potentially damaging speakers or hearing.
3. S3 balanced XLR outputs connected directly to a high-gain power amp is risky, even with only a small digital volume error.

If you try to correct possible safety issues by adding a downstream volume control it increases cost and may also add distortion to the audio chain. If you weigh speaker safety concerns, the S3 XLR outs may actually not be all that useful. Immature software simply adds to the risk.

I think you bring up a good point, but I am a bit confused. You are right to bring up XLR, but wouldn't this also apply to RCA? FWIW I am using the S3 with XLR feeding Fosi Monos. Without preamplification it maxes out at about 95db (so not very risky), and since I just use the app for control the very first thing I see when using the S3 is the volume level.

ETA: It's 95db max at 6 feet using 90db (supposedly) sensitivity Lintons. I asked FOSI and they said output voltage was the usual 2V RCA and 4V XLR, but in actual listening it appears to not be close to 4V, as I'm using an amp with 20db gain and about 140 clean watts into 6 ohms. It's 160 into 6ohm with 1%THD, manufacturer claimed, but their 4ohm claim was verified by ASR so I'm inclined to trust the 6ohm one.

 

[amper42]

I think you bring up a good point, but I am a bit confused. You are right to bring up XLR, but wouldn't this also apply to RCA? FWIW I am using the S3 with XLR feeding Fosi Monos. Without preamplification it maxes out at about 95db (so not very risky), and since I just use the app for control the very first thing I see when using the S3 is the volume level.

You are absolutely right that an RCA connection direct to power amp from S3 may be problematic as well. If the amp has its own volume control and you have tested full volume on the S3 to your amp setting and it doesn't over drive the speakers you are likely safe.

What I was mostly considering was our high watt Purifi and Hypex amp users who see a balanced out on S3 and an input on the amp and may not realize the potential safety concerns of such a direct match.

 

[OrangeWalrus]

What I was mostly considering was our high watt Purifi and Hypex amp users who see a balanced out on S3 and an input on the amp and may not realize the potential safety concerns of such a direct match.

@yuting

Problem: I have a concern about this as well, but in a different way that is a suggestion to you. On the app, it is possible to tap on the volume bar to change the volume. However, it is very easy to tap by mistake and accidentally tap very high volume. If someone has a high power amplifier, this could damage the speakers.

Potential solution: Is it possible to change the user interface to have an increase button and decrease button on the app, similar to the Bluetooth remote? Maybe also allow tapping on the volume bar, but only allow that up to the min/max startup volume. It's likely that not everyone would like this, but some will need this to protect their equipment. (I know that there is a maximum setting in the app, but different music can use very different volumes, such as classical music compared to electronic music, so the maximum is good, but may not be enough.) Thank you for considering this and your attention to customers.

 

[himey]

I'm new with Fosi Streamer S3 and I confirm its missing "points" in iOS app (latest version 0.2.0):

• UPNP not working with Lyrion Music Server (I get "Failed to retrieve content"), LMS UPNP perfectly worlking with oter apps/hardware
• Roon Ready is "not ready"
• No Qobuz

So, for me, is pretty unusable...
I hope it'll start working asap

PS: S3 appears in LMS as client (boh!!!)

If you connect to your LMS server from a browser, does the S3 show up, and is it fully functional after you add the UPNP add-on? This seems pretty basic. Right now, I am using a Mini PC with Foobar2000 as my LMS Music Server renderer. Eventually I would like to replace the PC with something like the S3.

 

[audioje]

As long as the app is good, this looks wonderful. Finally, a decent & affordable streamer with XLR output. I am willing to try.

 

[amirm]

2. Danger lies in potential software or hardware glitches that could reset the volume to 100% (fixed output), potentially damaging speakers or hearing.

There is nothing unique here to S3. This is quite safe unlike software volume controls in a computer where there is much higher chances of crashes, hangs, etc.

If you are going to worry about "hardware problems," then your DAC could short out and send out full DC to your amp. At Madrona we had a Berkeley DAC that did that. It drove ML 53 amps that were connected to demo loaner bookshelf speakers. With nearly 1000 watts on tap, it blew its woofer like nobody's business.

 

[Ruediger]

I see a lot of praise for XLR out on S3. I don't see prominent warnings about how unsafe it can be to connect a streamer like the S3 over XLR to an amp with no volume control like a Purifi or Hypex model. These amps tend to offer the quality many audio users look for and many of us own them.

The streamer brings many possibilities for user/error.

But any other preamp also has potential for hardware or sometimes software failure.

Max. volume, startup volume, gain per source etc. need to be set or considered by the user. And populated with good defaults.

With no other preamp in the chain a volume bar with fat finger support for max. output is indeed a bit dangerous.

 

[SanojS]

Why not value in asym and just sym?
(The other machines of the same type were measured asymmetrically. )
Imd?

Are measurements of the analog inputs coming soon? Or sub output?
;-)

Sub output is mostly a convenience feature in this type of kit. It is basically just full range combined L/R signal... so basically an internal Y-splitter. I guess it reduces the cables to one instead of using L/R cable to subwoofer...
I find it obsolete without bass management and high pass filter on mains...

 

[morillon]

Sub output is mostly a convenience feature in this type of kit. It is basically just full range combined L/R signal... so basically an internal Y-splitter. I guess it reduces the cables to one instead of using L/R cable to subwoofer...
I find it obsolete without bass management and high pass filter on mains...

It could also be considered as just 2+1 , which corresponds to the common usage of many...(although I also find that a shame)...
but we haven't had any feedback on the principles, the current adjustment possibilities for this output, dsp filter etc?...

what is the situation?

 

[yuting]

@yuting

Problem: I have a concern about this as well, but in a different way that is a suggestion to you. On the app, it is possible to tap on the volume bar to change the volume. However, it is very easy to tap by mistake and accidentally tap very high volume. If someone has a high power amplifier, this could damage the speakers.

Potential solution: Is it possible to change the user interface to have an increase button and decrease button on the app, similar to the Bluetooth remote? Maybe also allow tapping on the volume bar, but only allow that up to the min/max startup volume. It's likely that not everyone would like this, but some will need this to protect their equipment. (I know that there is a maximum setting in the app, but different music can use very different volumes, such as classical music compared to electronic music, so the maximum is good, but may not be enough.) Thank you for considering this and your attention to customers.

thanks，We are redesigning the app’s interaction. Currently, the volume control interaction has been updated to allow you to set maximum and minimum volume limits. We hope this solution resolves your issue.

 

[OrangeWalrus]

thanks，We are redesigning the app’s interaction. Currently, the volume control interaction has been updated to allow you to set maximum and minimum volume limits. We hope this solution resolves your issue.

@yuting I want to say how grateful I am to hear directly from the manufacturer and that you are taking the time to consider feedback from your customers.

 

[yuting]

@yuting I want to say how grateful I am to hear directly from the manufacturer and that you are taking the time to consider feedback from your customers.

thanks ,This is how we have always developed our products.

 

[Laserjock]

thanks ,This is how we have always developed our products.

Any thoughts on how the sub out is handled?

 

[yuting]

Any thoughts on how the sub out is handled?

Thank you. As this involves hardware modifications, the S3 currently cannot support this feature. However, our upcoming streaming amplifier products already incorporate bass management, and we expect to launch these products in Q4.

 

[anonyless]

Nice little Wiim Pro Plus competitor! Finally bringing XLR outputs into affordable streamers. Also eARC, sub out and trigger support.

Let's see in a couple of months if they can keep their promise of new services and features, but I have no reason to doubt them. Hopefully other higher end models come afterwards to complement their line. Congrats, Fosi!

"We see this not as a finished endpoint, but as the beginning of a long-term platform that will continue to improve with real-world input from the community."

Nice!

i hope Fosi (hi @yuting ) won't make the same mistake WiiM did with their "community" , by creating and maintaining forums for their products and allowing (and enabling) "super enthusiasts" users to basically run it and fill it with brand kissing content as they pleased

 

[amirm]

i hope Fosi (hi @yuting ) won't make the same mistake WiiM did with their "community" , by creating and maintaining forums for their products and allowing (and enabling) "super enthusiasts" users to basically run it and fill it with brand kissing content as they pleased

??? We are a big part of their community so don't see that happening.

There is danger of course that we ask them to do things that not useful, or doesn't increase success of the product. In that regard, we need to be measured with respect to what we ask them to do.

 

[F1Fan72]

“There is danger of course that we ask them to do things that not useful” Yes, like adding multiple alarm clocks and multi clock faces

 

[anonyless]

??? We are a big part of their community so don't see that happening.

There is danger of course that we ask them to do things that not useful, or doesn't increase success of the product. In that regard, we need to be measured with respect to what we ask them to do.

i'm talking about the same several users who lost their objectivity xxxx messages ago, and feel the urge to reply in every single thread. some of them are even official curators

 

[morillon]

i hope Fosi (hi @yuting ) won't make the same mistake WiiM did with their "community" , by creating and maintaining forums for their products and allowing (and enabling) "super enthusiasts" users to basically run it and fill it with brand kissing content as they pleased

It's very unfair because their forums aren't really filled with "fanboy" comments. Teally not...

Actually, it's quite the opposite... mainly requests for help, "complaints" about delays in certain developments, or countless ideas for things that could be added as features, "I would like Wiim to do in the future" (probably closely observed by Fosi ;-) (but surprisingly few about hardware support issues).

On the other hand,
Wiim was incredibly lucky because by investing in features like automatic roomfit, gestion of subwoofer etc, they had competent and generous people who dedicated a huge amount of time (and still do) to educating people on how to use it properly on their forum...

because it's not so simple and quite technical and they challenged Wiim to help them progress intelligently...
Wiim was very fortunate. because otherwise, these kinds of ambitious features implemented on very mainstream devices would never have come to fruition...

(Wiim was clearly discovering the world of audio as it went along.)