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Tests of Fade-In Behavior of USB DACs and DAC/HP Amp Devices

Intrigued by this post I wanted to double check on my JM20, and i can confirm it.
My tests are in Linux -> audio properties panel -> hardware -> select the device you want to test -> speakers test, clicking the 2 buttons you hear respectively "front left" and "front right"

Jcally JM20 (CS43131 - Savitech bridge - ASYNC usb)
high gain

no ramp-up\fade-in effect, you hear the entire phrase but with short pink noise in background for the first half second played when the device is idle (not playing) for at least 5 seconds.
low gain
no issue, you hear the entire phrase with clean background, no matters how much time you leave it idle

Then I wanted to re-check my other dongles, changing gain when it is possible:

Tempotec sonata BHD (dual CS43131 - Savitech bridge - ASYNC usb)
low gain - mid gain

ramp-up issue: clicking on "front left" you can only hear "left", then after 5 second clicking on "front right" you can hear "t right", so right channel come up a fraction earlier than left one (panning effect), both truncating the very first samples.
high gain
no issue, you can always hear the entire "front" word on both channels, no matters how much time you leave it idle

Kuang Pai Player 3 (dual CS43131 - Savitech bridge - ASYNC usb)
low gain - high gain

ramp-up issue: clicking on "front left" you can only hear "ont left", then after 5 second clicking on "front right" you can hear "ront right", so right channel come up a fraction earlier than left one (panning effect), both truncating the very first samples.
So it's a bit faster than Sonata (truncate less samples) but has the issue in any mode you use it

Ugreen HiFi Audio Pro (CS43131 - CS46L41 bridge - SYNC usb)
low gain - high gain

no issue, you can always hear the entire "front" word on both channels, no matters how much time you leave it idle

CX-Pro (Grave Audio DA06 CX31993 - TTGK brdge - SYNC usb)
only 1V mode

no issue, you can always hear the entire "front" word on both channels, no matters how much time you leave it idle

Hi-Max (CB1200AU chipset - ADAPTIVE usb)
only 1V mode

no issue, you can always hear the entire "front" word on both channels, no matters how much time you leave it idle

So, different behaviors, some devices are always ok, others change with gain mode, others are always affected. In my case the only common factors between the device that are affected by some extent is the Savitech bridge and the corresponding ASYNC usb transfer.
Maybe the JM20 pink noise is one of the artifacts that Fosi Audio referred to saying that the ramp-up was a necessary setting to avoid them, but it happens only in high gain, while Sonata is perfect in high gain and has the ramp-up in lower gain modes, so high variability and nothing can be concluded with confidence.

Did not run tests in other applications, since it is proven that depending on the application and how it keeps the device asleep the issue will not appear even if the device is affected, for example if i leave an audio editor like Ocenaudio with the dongle as output card, it is kept always asleep even if nothing playing.
From my point of view, if the issue appears in the OS speaker test, a device is to be considered affected.

Since my tests are under Linux they are not compliant to @jkim method, so I'm not going to update the spreadsheet and will leave the choice to him.
Very interesting findings. Aargh, gain or volume-limiting mode is another factor!

I have an old laptop which I wanted to turn into a Linux machine. I am going to test the dongles in Linux. Is there some reason to install a certain Linux distro for this purpose?

I can also test them on a Mac...
 
I appreciate this thread - this fade-up issue is something that drives me crazy and has limited my choices (or the choices I'm willing to consider) for my own setup.

In my case, I've noticed that when I feed my Mac mini music server into any digital switch or converter through USB, all is well. But when I use the Mini's optical/TOSLINK connection instead, I get the problem that is the subject of this thread no matter what digital switcher/converter/preamp I use with it.

That's not a big deal in and of itself, but as discussed in another thread, it indirectly creates issues because the options for inexpensive digital switchers (to use another digital source in addition to the mini and be able to switch between the two) are plentiful if you only need TOSLINK and SPDIF inputs into the switcher, but virtually nonexistent if you need to have a USB input on the switcher.
 
Very interesting findings. Aargh, gain or volume-limiting mode is another factor!

I have an old laptop which I wanted to turn into a Linux machine. I am going to test the dongles in Linux. Is there some reason to install a certain Linux distro for this purpose?

I can also test them on a Mac...

The only aspect that could be relevant for our goal is if the distro uses Pulse or Pipewire as sound server, but honestly I don't think it would affect the results.
I run Mint Mate 22.1 with Pipewire.
 
The only aspect that could be relevant for our goal is if the distro uses Pulse or Pipewire as sound server, but honestly I don't think it would affect the results.
I run Mint Mate 22.1 with Pipewire.
Just tested the JM20 and JM20 Max on Linux Mint Mate 22.1 (with default Pipewire).

I cannot hear the half-sec pink noise from the JM20 in either its low or high gain mode.

Both the JM20 and JM20 Max work flawlessly with no skips or noise.

Puzzling. Maybe some different versions of the JM20?
 
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Just tested the JM20 and JM20 Max on Linux Mint Mate 22.1 (with default Pipewire).

I cannot hear the half-sec pink noise from the JM20 in either its low or high gain mode.

Both the JM20 and JM20 Max work flawlessly with no skips or noise.

Puzzling. Maybe some different versions of the JM20?
Then I don't know...
Changes in different revision of the devices is indeed another element we shouldn't rule out, but at this point I think that the entire story is becoming a witch hunt that will hardly bring to significative results :\
 
Then I don't know...
Changes in different revision of the devices is indeed another element we shouldn't rule out, but at this point I think that the entire story is becoming a witch hunt that will hardly bring to significative results :\
How about hardware/driver differences of USB controllers?
 
How about hardware/driver differences of USB controllers?

This is how JM20 is seen by my Linux Mint:

lsusb
Bus 001 Device 003: ID 262a:0001 SAVITECH Corp. CS43131 HIFI Audio

pw-top
Shenzhen CBHT Technology Co., Ltd CS43131 HIFI Audio at usb-0000:00:1d.0-1.1, h : USB Audio

if yours is the same, then I wouldn't know what to check.
 
I will try to run some proper tests if I find some off time+bad weather :P in the following days, but I just gave JM20 a quick run to try it with an amp, since that what I bought it for and I sure am confused.

JM20 > L30 II (TPA6120A2), Windows 11 23H2, desktop
volume slider prompt - 100% loud clicks/pops as before
winamp - this time it is ok? there is a slight click but once in 10 starts, much less than previously
firefox browser - switching to a tab with a youtube's home page will occasionally freeze the playback of music in winamp for a second, I haven't observed that before

The differences - L30 II is a much higher impedance than HD600 which was the highest connected before, there is 1.5-2m quality cable between, I've used USB C port which I haven't previously (from Z690, USB 3.2 Gen 2x2 20Gbps, should be different channel/controller, also no C to A adapter), and removed some USB gamepads

HOWEVER
Creative Sound Blaster Z (CS4398, Max97220, PCI-e) > L30 II (TPA6120A2) - clicks and pops just the same, I don't recall having an issue on volume slider prompt before, but can't say I've paid much attention to it
Creative SoundBlasterX (CS43131, discreet amp) - no clicks or pops of any kind, volume slider is perfectly clean
JCAlly JM6 Pro (CX31993, Max97220) - pops and clicks again... I'm sure it was clean before!
Fx-Audio DAC-X6 (CS4399 + SA9023 variant, X6 uses CS4398/4399 with a variety of USB chips, TPA6120A2) - pops and clicks, although weirdly they feel a tiny bit lighter

Ran HD600, HD598SE, KSC75, and Snow Lotus 1.0 (64Ohm).

I did a proper off/on with JM20 disconnected, and I do have "Turn on fast start up" off in Control Panel\All Control Panel Items\Power Options\System Settings ("Choose what power buttons do").

I now wonder if the clicks/pops were always there, and I just started noticing them because that was what I was looking for when I've first used JM20 (since all the CS43131 reports) or is there something getting messed up in the OS after connecting JM20, but I'm quite sure JM6 Pro was fine previously, and now it is not anymore.
 
So after fiddling with the JM20 Max a bit today, I've found some ways to mitigate the fade in issue when starting playback in various players.

Using MusicBee on Windows 10 in WASAPI exclusive mode, I enabled "Play some silence at startup for hardware synchronization" under the Player options in the Preferences. After a slight delay, music starts normally with no fade in / ramp up or crackles or hiccups, etc.

On Android with UAPP, I dug around the settings for a similar option and found "DAC Warm-Up Time" in the settings under "USB Audio Tweaks". Adding ~500ms of delay seems to cover it, resulting in a clean start to playback with no fade in.

I also use MediaMonkey on Windows, but haven't found a similar setting to delay the start of playback to avoid the fade in. But selecting 'DirectSound' as the output and starting playback, I get the fade in -- but if I stop the playback and start again, the music plays normally as though the dongle 'stays awake' and doesn't need to ramp up again. The 'cold start' gets me the fade in, but for some reason using MediaMonkey in this way keeps the dongle active so if I stop and start playback or try something like the Windows test chime or playing in foobar I don't get the ramp up.

Kind of annoying behaviour, and to be honest if I'd seen anyone else mention this quirk earlier I probably wouldn't have the purchased the JM20 Max. But after figuring it out this much, I'll go on using it.
Ok, I have tested my JM20 Max on four different Windows 11 laptops so far. None of the cases gave a fade-in or skip. At this point, it's either of the two possibilities: (a) my JM20 Max is a different revision from yours; or (b) the problem is not specific to the JM20 Max itself and hence should not be attributed to the dongle.
 
Ok, I have tested my JM20 Max on four different Windows 11 laptops so far. None of the cases gave a fade-in or skip. At this point, it's either of the two possibilities: (a) my JM20 Max is a different revision from yours; or (b) the problem is not specific to the JM20 Max itself and hence should not be attributed to the dongle.
It's entirely possible that there is some difference with JM20 Max versions. But as I've mentioned before, the other dongles I have don't all behave identically. The Apple and Meizu dongles clearly have fade in (they are both CS-based). But the Samsung dongle starts normally. I have two CX31993 dongles that also start playing normally, but they have their own issues... they crackle when I plug headphones into them and they autoplay upon connection (this really annoys me so I don't use them). And perhaps most interestingly, using different firmware on my Jcally JM12 yields different start up behaviour from the same dongle! So perhaps there is some slight difference with JM20 Max versions. I doubt it's some quirk with my PC, because the dongles behave similarly on my Android device.
 
Then I don't know...
Changes in different revision of the devices is indeed another element we shouldn't rule out, but at this point I think that the entire story is becoming a witch hunt that will hardly bring to significative results :\
It's entirely possible that there is some difference with JM20 Max versions. But as I've mentioned before, the other dongles I have don't all behave identically. The Apple and Meizu dongles clearly have fade in (they are both CS-based). But the Samsung dongle starts normally. I have two CX31993 dongles that also start playing normally, but they have their own issues... they crackle when I plug headphones into them and they autoplay upon connection (this really annoys me so I don't use them). And perhaps most interestingly, using different firmware on my Jcally JM12 yields different start up behaviour from the same dongle! So perhaps there is some slight difference with JM20 Max versions. I doubt it's some quirk with my PC, because the dongles behave similarly on my Android device.
In the meantime, there is a way to determine the revision (or firmware version), which might give you an idea of whether it is different or not.

HWiNFO

USBDeview

Using these tools, you can check the firmware version.
Well, you can also check from Device Manager...
("REV_XXXX" part of "USB\VID_XXXX&PID_XXXX&REV_XXXX")
 
In the meantime, there is a way to determine the revision (or firmware version), which might give you an idea of whether it is different or not.

HWiNFO

USBDeview

Using these tools, you can check the firmware version.
Well, you can also check from Device Manager...
("REV_XXXX" part of "USB\VID_XXXX&PID_XXXX&REV_XXXX")
This assumes the OEM actively maintains these fields, correct? The reason I mention that are these devices where the REV is "0000"...
 
This assumes the OEM actively maintains these fields, correct? The reason I mention that are these devices where the REV is "0000"...
Probably.
FYI, the firmware revision of my JM30 that causes the symptoms is “0.08”.
 
Probably.
FYI, the firmware revision of my JM30 that causes the symptoms is “0.08”.
The idea is interesting but @CedarX may have a point, just checked my JM20 and it is also 0.08

Vendor: usb 0x262a "SAVITECH Corp."
Device: usb 0x0001 "CS43131 HIFI Audio"
Revision: "0.08"

It has the "pink noise ramp-up", not the "fade-in" one.
 
This is not relevant to this product and this particular issue. Moreover, I doubt very much that the manufacturer in Shenzhen or Guangzhou or wherever it is cares about which directives the EU has in place.

And still, whatever the excuse, if some behavior of a product interferes with its normal operation, it's a defective product.
 
The idea is interesting but @CedarX may have a point, just checked my JM20 and it is also 0.08

Vendor: usb 0x262a "SAVITECH Corp."
Device: usb 0x0001 "CS43131 HIFI Audio"
Revision: "0.08"

It has the "pink noise ramp-up", not the "fade-in" one.
I see. Then I guess we can rule out this idea.
Thank you for confirming.
 
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