Fosi Audio DS2 Portable DAC & Amp Review

[danadam]

+50% max perceived loudness (+6dB).

Isn't +6dB just double the voltage while for double perceived loudness you need +10dB?

 

[staticV3]

Isn't +6dB just double the voltage while for double perceived loudness you need +10dB?

Correct.

+6dB = double the voltage = +50% perceived loudness.

 

[Eddie]

This is an on-topic post.

I received my DS2 today, plugged it into a USB port on my Windows 10 computer and the only thing I did was to run Windows' basic audio device test:

(The screenshot shows my old E-MU 0204 | USB for illustration purposes only. Read on if you want to know why.)

The result of this test is even worse than with Tanchjim SPACE: only the very last milliseconds of the chime sound are played. In all 24 formats and on both channels, the beginning of the sound is skipped and faded in.

Then I unplugged the device and plugged it back in.
Now Windows no longer recognizes it.
Instead, the device's LED lights up blue which means DSD even though the above test does not play DSD.

I will return this thing immediately. This is the worst experience I have ever had with a USB audio device.
Judge and try for yourself, but my conclusion is: it's unusable under Windows 10.

 

[alexanderino]

Now Windows no longer recognizes it.
... my conclusion is: it's unusable under Windows 10.

Works fine on my Windows 10 machine. Try rebooting your PC. Also, do you have another Win10 PC for testing purposes?

The result of this test is even worse than with Tanchjim SPACE: only the very last milliseconds of the chime sound are played. In all 24 formats and on both channels, the beginning of the sound is skipped and faded in.

This mirrors my 'chime test' experience as well (on both Windows 11 and 10) [EDIT: just tested it again on Windows 11, works almost flawlessly. I think that's because it was playing audio before I stopped it to test. Changing the sample rate and then playing the chime results in your experience]. Nonetheless, for listening to music or general-purpose listening on my PCs, the initial fade-in issue is nowhere as drastic.

Having said that, I would like a firmware update (or alternative firmware) that provides uninterrupted sound, even if it means sacrificing the fade-in. @Fosi Audio, is this possible?

 

[Eddie]

Works fine on my Windows 10 machine. Try rebooting your PC. Also, do you have another Win10 PC for testing purposes?


This mirrors my 'chime test' experience as well (on both Windows 11 and 10) [EDIT: just tested it again on Windows 11, works almost flawlessly. I think that's because it was playing audio before I stopped it to test. Changing the sample rate and then playing the chime results in your experience]. Nonetheless, for listening to music or general-purpose listening on my PCs, the initial fade-in issue is nowhere as drastic.

Having said that, I would like a firmware update (or alternative firmware) that provides uninterrupted sound, even if it means sacrificing the fade-in. @Fosi Audio, is this possible?

Thanks for your reply.

I rebooted my PC and plugged in the DS2. It's still not recognized.
I tried all available ports, including the one on which the E-MU 0204 | USB is recognized as always.
No chance. And the LED is still blue.

Before I give up, I will test this thing on two other PCs later.
Maybe Windows' basic audio device test was too much for my unit and just broke it...

By the way, the cheap Realtek onboard audio device on my PC's mainboard passes the above test flawlessly.

 

[alexanderino]

Before I give up, I will test this thing on two other PCs later.

If you can access an Android phone, it's worth a try.

Maybe Windows' basic audio device test was too much for my unit and just broke it...

In my experience, it has been useful for testing many USB DACs. Does your E-MU 0204 pass it? Of course, if it needs drivers to work with Windows, that may solve any problems.

By the way, the cheap Realtek onboard audio device on my PC's mainboard passes the above test flawlessly.

Probably because it's not USB-based.

 

[Eddie]

If you can access an Android phone, it's worth a try.

My Android phone does not have USB-C.

Does your E-MU 0204 pass it?

At most sample rates, yes. For some it may click and pop and swallow the first few samples. It behaves this way on all tested computers.
But that device is from 2011 and requires a USB driver from the manufacturer which was never great.
Unlike the DS2, it's not usbaudio2.sys compatible.

Probably because it's not USB-based.

Yes, probably. I just wanted to point out that even the cheapest devices can pass this test.

 

[roladyzator]

My unit (received new, 2 days ago) is going silent for a very brief moment, then restores the volume (with the fading mentioned in this thread already).
It happens at random times during playback, (once every few minutes).

This is happening on my work laptop (streaming using tidal, with Ears extension that gives you parametric EQ in the browser). Not sure yet if this happens on my personal laptop. It can be made much worse if my wireless mouse / keyboard adapter is in a specific USB port.
I tried things like finding the process ID of the Tidal tab and increasing the priority to High in task manager - but those random dropouts still occur.

Same thing on my phone with UAPP. I've mitigated it a bit by going to USB tweaks menu and increasing buffer size and adding 500 ms for warm-up.
I'm not getting this with any other USB DAC.

When I have some more time to test with my personal laptop, I'll check things like hardware latencies or whether it doesn't happen with Fosi's drivers, but it already seems that the device is extremely sensitive to any buffering issues that don't cause any trouble on other devices.
Too bad, I really wanted to keep it, but looks it'll have to go back.

 

[Eddie]

Fosi's drivers

Which drivers do you mean? Are you on Windows? AFAIK, there are no drivers required because it's UAC-2 compatible. That is, plug and pray.

 

[roladyzator]

Which drivers do you mean? Are you on Windows? AFAIK, there are no drivers required because it's UAC-2 compatible. That is, plug and pray.

I'm on Windows.
There are some ASIO drivers on the DS2 download site.
I presume they allow controlling the audio output buffer size - but maybe they don't.
See the bottom of this page.

Fosi Audio Product User Instruction DS2 (2024)

Design by GemPages

fosiaudio.com

 

[Eddie]

Ah, I see, you mean ASIO support. I thought you meant USB drivers.
ASIO itself is not a driver, it's just an audio API implemented in a DLL which in turn uses operating system audio APIs.

As an alternative, you could also try ASIO4ALL. It allows control of output buffers, too.

 

[roladyzator]

Yes, I know, I was referring to drivers for supporting the ASIO protocol that Fosi shared.

I'm not sure if I have a defective unit, or if my sources are particularly bad with USB DACs.
If these were just micro dropouts, it would be a non-issue.
But with DS2, the fade-in triggers in those moments, exaggerating the problem to absurd levels.

Best I can do (with buffers maxed out in my phone's UAPP app) is a drop every 5 to 10 minutes.
Doesn't sound like much but it does detract from otherwise good experience.

 

[Eddie]

If these were just micro dropouts, it would be a non-issue.
But with DS2, the fade-in triggers in those moments, exaggerating the problem to absurd levels.

Best I can do (with buffers maxed out in my phone's UAPP app) is a drop every 5 to 10 minutes.
Doesn't sound like much but it does detract from otherwise good experience.

I can understand that this is unacceptable, especially since these issues do not occur with other USB DACs on the same computer and phone.
Or your unit may really be defective, just like mine.

 

[Somafunk]

I will return this thing immediately. This is the worst experience I have ever had with a USB audio device.
Judge and try for yourself, but my conclusion is: it's unusable under Windows 10.

I’d keep the dongle, and return the windows 10 machine

 

[ShelteringSky]

I created an account to post this - I have been waiting for a device like this to hit this price point. Excellent all around! Thanks for making a great product, and thanks Amir for running this site!

 

[roladyzator]

I can understand that this is unacceptable, especially since these issues do not occur with other USB DACs on the same computer and phone.
Or your unit may really be defective, just like mine.

I've read through reviews on Amazon and one reviewer complained about getting no sound with one device and sound dropouts with other devices.
Those did go away after changing the cable from the bundled one to a phone charger cable.

With a USB-C cable from my Samsung phone charger, I've only got the issue with sound dropping out once with my phone, but didn't get it later.
With my personal laptop (an old Lenovo T460S from 2016) and a USB-A to USB-C cable from an even older Samsung charger, the issue didn't occur to me even once.
And I did have the wireless mouse+keyboard USB transmitter connected.

Without an oscilloscope I can't really say what's the difference in the electrical signal at the DAC input, but that does give me some hope it would work.

 

[renaudrenaud]

I’d keep the dongle, and return the windows 10 machine

Yes, no problem with all my Linux es machines, Debian Ubuntu PopOs and Android smartphones. Can't understand why people use Windows these days.

 

[elchupahueso]

Picked this up as part of the 7th anniversary sale, just arrived like 30 minutes ago. Plugged it into my android phone and put my IEM's in. I've pulled up FLAC files i'm extremely familiar with and i'm very happy with the result. Had been using the apple USB C -> stereo out connector. Honestly feels like a veil has been lifted.

 

[LtMandella]

All I see on my order from a couple days ago on the FOSI site is: Standard Shipping (5-15 days)

Well I would never order direct from FOSI again. Their shipper claims the item was delivered today but nothing arrived. So I put in a claim with Paypal but who the heck needs such hassle. Never do I have a problem with Amazon deliveries.
That's what I get I guess for ordering something directly from China...

 

[Basilderat]

I'm on Windows.
There are some ASIO drivers on the DS2 download site.
I presume they allow controlling the audio output buffer size - but maybe they don't.
See the bottom of this page.

Fosi Audio Product User Instruction DS2 (2024)

Design by GemPages

fosiaudio.com

You could try the ASIO driver that Fosi recommends for DSD playback on Foobar, might work with ASIO in general, worth a shot:

https://support.fosiaudio.com/hc/en-us/articles/32879080134937-How-to-Set-Up-the-New-DS2-on-Foobar2000