Fosi Audio DS2 Portable DAC & Amp Review

[SanojS]

Reserved for @AdamG to kindly post the specs.

Manufacturer Specifications:

View attachment 393004

The headphone Output Mode is wrong - should be 3.5mm and 4.4mm - not 6.35mm...

 

[SanojS]

Hi and welcome to ASR.
Honestly no idea about this issue, I'm using the Player 3 with Sgor Luna (Planar - 27 ohm - 96 dbmW) on the balanced output in low gain mode, never got any strange noise and the dongle never shown any sign of heating. If with Artti T10 it's ok it doesn't seems something related to impedance load, unless there is something with the PR2 sensitivity. They are rated at 94 db not specifying if dbV or dbmW, if it is dbmW (as i suspect) they are pretty similar to T10 while if it is dbV, @ 16 ohm it would equate to 75 dbmW, a pretty low sensitivity i've never seen on any other iem. But then I think the problem should be present and even worsen with unbalanced connection.

Do you use the same balanced cable also with T10? Maybe something with the 4.4 mm plug not perfectly inserted? I can say that both the headphone sockets of the Player 3 don't have a super solid feeling when plugging\unplugging the cable, they don't produce a nice click and feel somewhat "rubbery", but never had a real problem with both.

if you have a high/low gain mode, then you have the pre-2024 ESS version, not the latest Cirrus Logic version tested here

 

[SanojS]

Hello everyone! this is my first post after reading some reviews here and having bought the Fosi DS2 because of its technical achievements.

I can confirm the annoying ramp up (or fade in) effect: this device is the nemesis of any system of notifications, already based on this I wouldn't recommend it to anyone.

Based on my tests:

• On a Dell XPS 15 9500 with Windows 11 (the company laptop) I have experienced drop outs while listening to music.
• On my PC with Fedora 41 or a Samsung S23 (even this from my company) I haven't experienced drop outs while listening to music.

I would not recommend it at all for a Windows user, the driver from their site in my case causes even more frequent drop outs, buying this using Windows is a gamble.

On Linux you can remove the ramp up effect (hence it can work well for notifications) doing a loopback with no sound, something like this:
pactl load-module module-null-sink sink_name=keepalive
pactl load-module module-loopback source=keepalive.monitor

With the Samsung S23 I also heard some strange electrical noise (mainly while physically moving the DAC) but for now it doesn't seem serious.

My headphones are the Sennheiser HD 599 SE and before buying the Fosi I have bought a UGREEN USB-C to jack DAC.
I have bought the Fosi out of curiosity seeing this review and because I was thinking that the UGREEN was "too cheap to be good".
Between them the UGREEN is the clear winner for my use case and setup:

• I don't ear the difference probably because the 599 SE are really easy to drive;
• It doesn't ramp up or drop out sounds on any of my devices;
• It is more portable (even if I don't care too much about this, the Fosi is already "enough portable" for me);
• It is cheaper, 10 euros vs 60 euros for the Fosi.

The only thing which is really important but I can't assess right now is the durability of both these DACs, time will tell.
The software and firmware issues with the Fosi in my opinion are a deal breaker, I will keep it but probably don't use it much.

In the end it was a waste of money for me but at least now I have some more experience about this stuff.

Thanks for reading, I hope that you find this useful!

Out of curiosity, do you have the orignal DS2 (with ESS) or the latest one 2024 model with Cirrus Logic?

 

[SanojS]

Just a brief follow-up to this - I've moved my office recently with the result that I can now use my RME ADI-2 DAC with the new super-duper Windows 11 laptop. In all fairness to Fosi, the RME is just as bad for crackles and pops and dropouts. You don't get the weird fade-ins, but the DAC is more or less unusable with this ostensibly state of the art portable computer. So it seems that the only DAC I have that works properly with a Windows 11 computer with all the latest top of the range hardware is a prehistoric Arcam rPAC!

I have the DS2 2024 version and use it with the work PC (Windows 11, HP Elitebook), and I have no issues playing at all.
No drop outs, no crackles or pops. No fade-ins.

 

[Cippo95]

@SanojS The manual says that I have the Dual CS43131, hence the Cirrus Logic.
It is interesting that you don't have the fade-ins, I can replicate them on any device with this DAC, it really seems firmware as others confirmed previously.

@Basilderat I have tried again the BravoHD driver and it just has drop outs every second or so, the basic Windows driver it drops once in a while.
Furthermore I have just tried to open the panel of the driver and I have to use compatibility mode (Windows 8 works) or it won't open.

 

[mc.god]

@Basilderat I have tried again the BravoHD driver and it just has drop outs every second or so, the basic Windows driver it drops once in a while.
Furthermore I have just tried to open the panel of the driver and I have to use compatibility mode (Windows 8 works) or it won't open.

It's kinda strange, BravoHD control panel is working totally fine on my windows 10 desktop recognizing both Jcally JM20 and Sonat BHD.
Don't know what version you have, on Fosi site i only see a DS1\DS2 driver that seems to be for Comtrue bridge, not Savitech, maybe for DS2 old version, here is the newest BravoHD i could find in case you wanna try:
https://hifimediy.com/download/SaviAudioBravoHDSwPkg_HsDriverASIOiAP_20230901_v3p13p0p55.zip

[EDIT]
uhm, ok, i found the DS2 2024 driver wit BravoHD but now i'm on linux and can't check if it is newer than the one i linked.

 

[Cippo95]

It's kinda strange, BravoHD control panel is working totally fine on my windows 10 desktop recognizing both Jcally JM20 and Sonat BHD.
Don't know what version you have, on Fosi site i only see a DS1\DS2 driver that seems to be for Comtrue bridge, not Savitech, maybe for DS2 old version, here is the newest BravoHD i could find in case you wanna try:
https://hifimediy.com/download/SaviAudioBravoHDSwPkg_HsDriverASIOiAP_20230901_v3p13p0p55.zip

The panel says "savi audio" at the bottom, I have downloaded the driver from here: https://fosiaudio.com/pages/user-instruction-ds2-2024
Trying to install your drivers over mine it says that mine are newer.

I think that this device doesn't work well with this portable PC (with Windows 11 fully updated), it could work well with others.
Sadly I have this experience but also others in this thread have reported drop out issues with Windows, I'm not the first.

Here you can hear the drop outs on a sine wave at 440Hz if you want.

As said with my other PC with Fedora 41 and the Samsung S23 it just has the ramp up/fade in effect.

 

[Basilderat]

@SanojS The manual says that I have the Dual CS43131, hence the Cirrus Logic.
It is interesting that you don't have the fade-ins, I can replicate them on any device with this DAC, it really seems firmware as others confirmed previously.

@Basilderat I have tried again the BravoHD driver and it just has drop outs every second or so, the basic Windows driver it drops once in a while.
Furthermore I have just tried to open the panel of the driver and I have to use compatibility mode (Windows 8 works) or it won't open.

What Windows application are you using for playback? I use Foobar2000 v2.24 (x64) with the 'ASIO Proxy for foobar2000' application and 'foo_asio_dsd' component so hardware access is exclusive. I wonder if interrupts from another process might be responsible for the issue? It also seems strange that the BravoHD systray panel can only be opened in compatibility mode. Does your company laptop have any appsense or security software that might be affecting this?

 

[Cippo95]

What Windows application are you using for playback? I use Foobar2000 v2.24 (x64) with the 'ASIO Proxy for foobar2000' application and 'foo_asio_dsd' component so hardware access is exclusive. I wonder if interrupts from another process might be responsible for the issue? It also seems strange that the BravoHD systray panel can only be opened in compatibility mode. Does your company laptop have any appsense or security software that might be affecting this?

I'm just listening music on the browser, I'm an average guy.

The portable PC has a Trend Micro antivirus installed by my company, it usually shows if it blocks something for some reason.
But there's other bloatware from Dell as the MaxxAudio stuff, the issue could be there, who knows.
As said many times I agree that it could be this particular portable PC, but it is interesting that I don't have any issues with the UGREEN dongle.

However I just wanted to share my experience with the Fosi DS2 with Windows and confirm that I have drop outs there, and the fade in also on Linux and Android, stuff already reported by other users and I would not recommend this DAC because in my opinion it has too many issues, your mileage may vary.

At this point as I have already said I wasted money on this DAC, now I'm also wasting time which is worse for me.
It is just my experience and if I will do any further test and find the culprit of the drop outs I will write it here, be sure of it!

 

[MC_RME]

You have a Dell notebook? Start Latency Monitor from Resplendence, that should explain it.

Resplendence Software - LatencyMon: suitability checker for real-time audio and other tasks

LatencyMon: suitability checker for real-time audio and other tasks

www.resplendence.com

 

[MC_RME]

@SanojS The manual says that I have the Dual CS43131, hence the Cirrus Logic.
It is interesting that you don't have the fade-ins, I can replicate them on any device with this DAC

Anyone can unless the player takes care of that (constant playback mode or other workarounds). @SanojS will have to provide a lot of details to convince me there is a newer S2 firmware that has fixed that. And even if, anyone here bought it already, so only an available firmware update (!) would help.

 

[Cippo95]

You have a Dell notebook? Start Latency Monitor from Resplendence, that should explain it.

Resplendence Software - LatencyMon: suitability checker for real-time audio and other tasks

LatencyMon: suitability checker for real-time audio and other tasks

www.resplendence.com

Yes, a Dell XPS 15 9530 provided by the company where I work (I'm a software developer), in my free time I use my PC based on AMD's AM4 with Fedora 41.

Unfortunately the DPC latency measured by LatencyMon is bad.
Looking online ACPI.sys is related to power management, it is a common issue on many portable PCs and I can't do much about it.

I have to say that the UGREEN dongle, the HDMI audio and the internal audio work fine, without drop outs.
As said also others in this thread reported the same drop out issue, it can well depend on the portable PC used.

I'll add that years ago I had an Intel PC with Windows, it had DPC issues in LatencyMon but using it everyday it didn't had any audible issue, in my opinion it would be fun to ask to random people, even if they don't hear issues, to run LatencyMon and see the results, I think that we would be surprised.

However yesterday I have discovered that I can return it even if I have used it and I'm going to, I don't want to lose any more time on this.
It was fun seeing so many replies but I won't test this DAC anymore, it is just unproductive and frustrating.

PS: Even the fade-in issue in my opinion is not acceptable, if you use your PC or smartphone normally it will ruin your notifications.

 

[Labjr]

IMO, this DAC is a great value. It outperforms DACs costing thousands not that long ago. I wouldn't use it to replace the sound card in my PC because the sound quality of my PC isn't important to me. But before returning, I'd find a use for it as a DAC/headphone amp in another system.

 

[Cippo95]

@Labjr It is just my opinion and I'm free of returning it after seeing that it has software and firmware issues for my usage with 3 systems, if you like it you are free of keeping it.

 

[MC_RME]

Yes, a Dell XPS 15 9530

Guess on what I am typing...

Unfortunately the DPC latency measured by LatencyMon is bad.

Of course - it's a Dell!

I have to say that the UGREEN dongle, the HDMI audio and the internal audio work fine, without drop outs.

Not sure about the UGREEN dongle, but it might use a different USB transfer method. The other stuff is not USB anyway and could therefore perform better/unaffected.

BTW, I was able to significantly improve the 9530's DPCs by using special tools and specific power plan settings. But won't publish that as it is very specific and won't help others at all.

 

[Psinet]

I was having problems with this dongle until I replaced the cable I was using. No more dropouts or fades on either Android or Windows 11

 

[OlentoTM]

I was having problems with this dongle until I replaced the cable I was using. No more dropouts or fades on either Android or Windows 11

Same here. I bought the Type-C to Lightning DAC adapter cable from Fosi with my DS2 so I could use it with my iPhone 14. Kept getting dropouts almost every track I played making the DAC pretty much unusable. I was about to return it but decided to try it with a different cable first (Fiio LT-LT3 to be exact) and now it works fine. Something seems to be wrong with Fosi's own cables.

 

[AdrianusG]

I was having problems with this dongle until I replaced the cable I was using. No more dropouts or fades on either Android or Windows 11

Unfortunately, i'm experiencing more and more dropouts, and that's while using it with my phone, didn't even try to use it with my Lap-top (I have a dedicated DAC for that).
So i will try it with another cable as soon as i have one USB-C >USB-C

At current it has become unlistenable, several dropouts in every song now

 

[Kuma]

Likewise on dropouts. It was working fine for a few months until tonight. Now experiencing complete dropouts every 30 seconds or so. Unusable in its current state.

 

[Viper780]

Try a different cable