Hiss problem A50+

Hello,
I experience a quite noticeable hiss from my A50+ when i listen to rather quient parts of music independent of the source (almost no hiss if no music at the input- guess there is a treshold). Any idea whats the main cause of that and how I could fix it - power supply, amp hardware (e.g. decoupling capacitors) or anything I could maybe fix via the ACP workbench (i use EQ)?
I have the version of the A50+ with the TPA3116 configuration.
Would be great if you guys maybe have an idea where to look first.

Many thanks in advance,

Morris

Update: added additional 1200uF at the input and 1uF ceramic decoupling capacitor for the TPA3116. The hiss when there is no music playing (caused by the power supply) is now completely gone but that was not the problem as it was rather quiet anyway. The hiss while music is playing still is still more or less the same. It also stays rather constant independent of the volume. Any clues?
Also is it possible to get the schematic or at least the part of the output filter because I’m thinking of replacing the ceramic caps at the output with foil capacitors?

I’ve got the same hissing issue with my Arylic A50+. Tried different power supplies, no change. I purchased a couple of them and both have the same issue.

Not sure what it could be. As mentioned, I’ve tried hooking up different speakers, checking the ground is ok etc. I even tried moving them to different rooms and tried using it in a different home. Same issue. Seems to come from from the tweeters.

I eventually put it down to the poor quality sound floor of the A50+. I have never had it from other low cost amps and my higher end gear is very quiet.

Hi @Dean,

From which input through do you experience this noise thing? How did you calibrate the high eq?

Hi,

I’m getting the hiss/buzz regardless of the input. I tried connecting a CD player through toslink and have the same issue.

It’s just on the standard flat eq settings. Adjusting this seems to make no difference. Volume levels also don’t make any difference to the hiss/buzz.

Thanks for asking.

I also have an A50 +, but mine is completely noiseless. Either through tos-link or listening to radio streams. In both cases you will hear a small click when the signal source starts. It is possible that there is a noise gate that is on for me (and if there is no signal it will close) and yours is inactive. Try checking it with ACPWorkbench (unfortunately this is provided by Arylic for money).

Thanks for the tip. I guess it’s a quality control issue.

I’ll do some measurements during my summer job in july and try to locate the noise source - if I find a way to fix it I’ll give you a update.
Could be that zitev has another version of the amplifier as it’s build with 3 different chipsets.


http://192.168.xxx.yyy/httpapi.asp?command=getStatusEx
“language”: “en_us”, “firmware”: “4.6.415145”, “hardware”: “A31”, “build”: “release”, “project”: “ARYLIC_A50TE”, “priv_prj”: “ARYLIC_A50TE”, “project_build_name”: “a31rakoit”, “Release”: “20220427”

Okay then its the same hardware :slight_smile: And you experience no audible hiss at all while playing music if there is a quiet part?

@Morris I have been using it in the bedroom for a couple of months with two large 8ohm standing boxes. It is on 24 hours a day (I don’t usually turn it off, the status LED is dimmed and that’s it). It didn’t even show that there was any noise coming from the speaker, not even leaning close to the tweeter.

If its just “on” i have no noise as well but if a song i playing and there is a quite part there is quite some hiss there

Ohh i hear this. I generated a 10 minutes long, silence wav (44.1kHz/16bit, stereo, -120dB), and played it on the device. The noise is constantly present, regardless of the volume setting, the closing noise gate nicely “covers up” the problem. The cheap D-Class power amplifier IC is probably the weak link, but the device itself is not an audiophile category, just a cheap, compact music player, so the goal is approx. meets (I use it almost exclusively for TV sound).
There is some measurement about A50: Arylic A50 Review (wireless amplifier) | Audio Science Review (ASR) Forum
Distortion increases roughly at 4 ohms, which is why it’s not worth loading with 4-ohm speakers…

Agree - it’s okay as long as you dont want to listen at a low levels. I dont think its caused by the TPA3116 chip itself because there are many decent amplifiers running with it- even though it’s not a high end chip for sure - my guess is that either it happens before the amplifier or its the output filter. I’ll keep you posted if I find an easy fix for the problem.

It honestly didn’t show up until i put my ear on the tweeter while silence.wav was playing. Anyway, my cellphone’s amplifier behaves the same way … I don’t think it’s noisy before the power amp, because during playback, the noise level is constant regardless of the volume (and if it’s at the input, it would change by adjusting the volume).

Mine does this too. Very noticeable hiss at all times and in all modes unless the A50+ is in sleep mode. Makes it impossible to enjoy the unit and I wish I could return it.

My A50+ arrived today and I have the same hiss noise issues as described in this thread. Did you guys find any solution for this?

I only tried streaming from Spotify until now and I hear the noise in silent parts of the music and when I set the A50+ to mute while playing a song aswell. The noise will stay until the amp is switched off after around 30 seconds. When pressing mute the noise often starts as something similar to a white noise but then changes to a more digital sounding high frequency stuttering after some seconds.

I have the same firmware as the others here and there is no new firmware available as of now.

Here is a short video demonstrating the issue:

https://drive.google.com/file/d/1x05lgfVHB1Nw1KQaTMqVWDgKRFiSmPrP/view?usp=drivesdk

Is there a solution for this? I really wanted to like this amp…

:-/

@Fruehbel Huh that’s rough! I didn’t notice such a strong hum with mine, but the static noise is there. Unfortunately, this is probably a design flaw, all devices are like this, due to the cheap parts. A firmware will not fix this. Try it from another source, e.g. by playing a prepared file with a volume of -90dB, but a similar result will be obtained, I suspect that the input of the dac or the final stage IC is noisy…

Thanks for your reply zitev,
I’m still a bit puzzled where this digital stutter noise/hum is coming from then. In a German Forum I read about someone being able to reduce the noise by tuning it with the ACP workbench. Did you try this? Someone said he disabled (sic!) Noise reduction and another one said he reduced the preamp level.

I just ordered a ACP workbench license to try myself but I’m still waiting for the license number…

@Fruehbel I am not a friend of such solutions. On the one hand, a device should sound as good as possible out of the box. On the other hand, I think that a software adjustment can do more harm to the sound than if we leave the parameters of the signal linear. And thirdly, if a device basically needs a software configurator for good sound, then the manufacturer should provide it free of charge to the customer, because it is not so cheap anymore and just gives the impression of pulling off another fox skin…

Yes, I totally agree with you. I have not seen the options available with the ACP workbench yet because of the lack of the license key, but my assumption was, that maybe there is already a software adjustment in the DSP that causes this noise problem. So the idea was to disable some stuff that is activated by default and not to turn something on additionally.
But I will try my best once the license is here and report back if I could change something for the better or for worse. :wink: