Fosi Audio DS2 Portable DAC & Amp Review

[someAudioDude]

Upon further investigation I think that the cable is bad and this causes the drop out. I don't know why there is no drop out listening from the mac but I don't seem to be having drop outs with another cable. WTF??? A faulty cable is a thing nowadays? The original cable is very coool though, it's flexible and short I'm not sure i'll be able to find a replacement.

 

[CedarX]

Upon further investigation I think that the cable is bad and this causes the drop out. I don't know why there is no drop out listening from the mac but I don't seem to be having drop outs with another cable. WTF??? A faulty cable is a thing nowadays? The original cable is very coool though, it's flexible and short I'm not sure i'll be able to find a replacement.

If the cable works with your Mac, not with your phone (dropouts), but another cable works fine with both, it would indicate a connector problem. Have you checked the USB port on your phone (cleaned it)?

 

[someAudioDude]

If the cable works with your Mac, not with your phone (dropouts), but another cable works fine with both, it would indicate a connector problem. Have you checked the USB port on your phone (cleaned it)?

Yeah but how??? If the port weren't in order then no cable would work.

 

[Labjr]

Yeah but how??? If the port weren't in order then no cable would work.

There's 24 contacts on a USB-C cable. Maybe some are dirty but not all.

 

[someAudioDude]

Yeah, I mean this can be reproduced every time: the original cable leads to a complete drop out on the phone in max 3 minutes. Only reconnect helps. On mac I do not have the drop out, another cable works on the phone without dropouts.

This is the most ridiculous and mysterious thing I've ever seen. There is something weird with the supplied cable as the tip appears to be 1-2mm longer than all the other usb c cables I have. So maybe it has to do with this.

 

[CedarX]

Yeah, I mean this can be reproduced every time: the original cable leads to a complete drop out on the phone in max 3 minutes. Only reconnect helps. On mac I do not have the drop out, another cable works on the phone without dropouts.

This is the most ridiculous and mysterious thing I've ever seen. There is something weird with the supplied cable as the tip appears to be 1-2mm longer than all the other usb c cables I have. So maybe it has to do with this.

Then you’re left with finding a cable you like, and that works with your phone. It’s gonna be a buy-first, try-next process…

 

[Attis]

I can't find it. Is it work with PS5 like the DS1?

 

[Linnie]

In it's recent issue # 2/2026, German audio magazine Audio-stereoplay reviewed this dac and published these measurements:

Description says:
"Left: No issues with frequency ranges (top 384 kHz, below 44,1 kHz).
Right: Even distortion spectrum; with 102 dB SNR (A-weighted / 1 mW) noise und distortion
below average (0,01 % THD). 3,5 mm plug: 1,6 / 2,0 V @
32 / 300 ohm; impedance: 1 ohm. 4,4 mm plug: 2,5 / 4,0 V @ 32 / 300 ohms, impedance: 2 ohm."

The distortion measurement looks very different from the graphs published here. I'm not an electrician or electrical engineer so I don't know if they show basically the same. Any comments if the measurements are comparable?

 

[staticV3]

The distortion measurement looks very different from the graphs published here. I'm not an electrician or electrical engineer so I don't know if they show basically the same. Any comments if the measurements are comparable?

I believe the right graph shows the residuals of an FFT of a 1kHz sine wave, so with the fundamental filtered out to show only N+D, played at 1mW output power per channel, sadly w/o specifying the load impedance and hence, without specifying the output voltage.

Direct comparison to Amir's results is therefore not possible.

 

[tccalvin]

I can't find it. Is it work with PS5 like the DS1?

It doesn't look like it.

 

[KSR1]

Hello. My first post here, i hope you can understand my german english.
I bought a Fosi DS2 a few days ago. I whanted a headphone-out (TRS) sounding better than the one, my Notebook has. A small tool, easy to be mobile. At home i use a USB Interface from Focusrite and Studiospeakers too. It should have a good quality so my Neumann HP wouldn't be "pearls for swine". As i use Studiomonitors for "HiFi" listening since 20+ years, after learning something about meassurements and acoustics, the measurements @amirm offers are very helpful! Well, the DS2 ist "compatible" to the NDH 30. I hope it will last long, some customers at Amazon wrote aboute trouble.
An other Headphone ist no Option. It is the only one i tryed not hurting my ears (Anthelix ). And it is compatible with good monitors.
Greetings from Germany, KSR1

 

[Alou]

Late night browsing the tests brought me here and saw that the DS2 tested here has a dual Cirrus Dac.I went to their site and saw that the DS2 has dual ESS dacs.
So is that a new version?If yes has anyone tested it ?How does it compare to the Cirrus version.

 

[Alou]

Well after searching here ,looks like the ESS was the older version!

 

[Viper780]

The old Version from 2023 had the ESS but since 2024 only the Dual CS43131 Version is available

 

[Alou]

The old Version from 2023 had the ESS but since 2024 only the Dual CS43131 Version is available

Yes thanks for your reply ,I found it after reading the posts.Seems strange to change their main Dac chips ,specially when Cirrus is almost in all of the dongle/ultra portable ones.

 

[Viper780]

Not really, the CS Chip with the buffers are a bit more powerful and measures better - but in a real world scenario both sound the same

 

[Alou]

Probably you are right,beside measurements and results i wonder if dongles with higher ESS chip would sound different .All my dongles are Cirrus based ,wonder if its worth to try an ESS one or in the end will be almost the same.

 

[pioterd]

i wonder if dongles with higher ESS chip would sound different

Fosi DS2 is reference-quality DAC/Amp. If you put strong enough "expectation bias" you will probably hear the difference using other well implemented chips. But you will just deceive yourself. We are able to hear what we expect to hear, according to neuroscientists:

We hear what we expect to hear

Dresden neuroscientists show that the entire auditory pathway represents sounds according to prior expectations. Their findings have now been published in the renowned scientific journal eLife.

tu-dresden.de

And me, and probably thousands other people, can confirm it practically, from experience. Life is better (IMO) without that expectation bias

 

[Alou]

Fosi DS2 is reference-quality DAC/Amp. If you put strong enough "expectation bias" you will probably hear the difference using other well implemented chips. But you will just deceive yourself. We are able to hear what we expect to hear, according to neuroscientists:

We hear what we expect to hear

Dresden neuroscientists show that the entire auditory pathway represents sounds according to prior expectations. Their findings have now been published in the renowned scientific journal eLife.

tu-dresden.de

And me, and probably thousands other people, can confirm it practically, from experience. Life is better (IMO) without that expectation bias

Oh yes there is always that factor!

 

[Viper780]

Probably you are right,beside measurements and results i wonder if dongles with higher ESS chip would sound different .All my dongles are Cirrus based ,wonder if its worth to try an ESS one or in the end will be almost the same.

I have Dual ESS9039Q2M-DAC-Chips in the Topping DX5 II and I can hear a slight difference between the DS2. I wouldn't consider one of them better.