Is this normal behavior? Squeked AX8

In case this helps someone at @FractalAudio comment on this, here's a waveform along with a spectrum analysis on the whining sound. The way I produced this:
1. Put two FET boosts in series, directly from input to output,
2. maxed out drive, tone and level (on both),
3. set noise gate threshold at -100dB,
4. had nothing plugged in,
5. engaged preset select mode, and
6. recorded the output with the s/pdif output. (I checked, and the same happens with the analog output also, unsurprisingly.)

First off, you can clearly see that the envelope is very "well behaved" and follows the led blinking frequency.
Second, you can clearly see a peak of about 24 dB above the noise floor at 4,8 kHz, and also a clear second harmonic at 9,6 kHz (about 12dB). You can also see a bit of the third and fourth harmonic also, and a bit of a subharmonic.

The peak being at 1/10th of the sample rate makes me curious, but I guess there could be something else running at that rate also...
 

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How much gain do the two drive blocks add? 120dB? I would be surprised NOT to hear any noise but I wouldn't expect it to be picked up from the LED controls.
 
The absolute amount of gain is not that relevant: The problem is that the whining sound is 24 dB above the noise floor, so quiet signals get overpowered by it. Also, some white noise, and perhaps 50/60 Hz hum would expected, but this is a whiny sound with a clear pitch. I can easily hear it with some high gain factory presets (by playing very very lightly to trigger the noise gate).

It's not really a deal breaker, as I won't be staying in preset select mode for long. Just wondering if this might be a symptom of e.g. a bad component or something else which might get worse over time.
 
You don't have to be in preset select mode to hear the noise, although that's where it's the most easily heard. But if you're in a normal preset and start engaging effects, the noise creeps in as more and more LEDs light up. With 4-5 effects engaged, and as a result 4-5 LEDs light up, you can hear the noise in normal preset mode as well.

And yes, some noise is to be expected. A little amp noise, hum and general noise will always be there without a noise gate. But this is a very distinct higher pitch noise louder than the general noise floor, as SaBer mentioned. And it's there even without anything plugged in. This doesn't automatically mean that it's something wrong, of course. But one starts to wonder.
 
Update:

After some communication with support at G66, it was decided to change the power supply in my AX8. The guys at G66 are really helpful and responds quickly, so that's good.

Sadly, however, changing the power supply did not work in any way. So back to scratch.

I have a gig coming up shortly, so we'll see if the noise is present there as well.
 
Ok, so I got a new device from G66 today, and no problems with it so far! The serial number starts with AX8-17-03, so I assume it's made in this years March. My previous one was from 2016 (sold this year).
 
I seem have the same issue here, even without distortion added.

I already had my AX8 exchanged by G66 due to some "zipper" noise, when rocking the wah forth and back. The problem was still there after the exchange. Now I assume, that the whining noise correlated to the LED's is emphasized by the wah filter?
 
@SaBer

Could you please confirm that the exchange of your AX8 to a 2017 model really solved the issue for you, after you had the change to restore/test all settings and configurations thigt might contribute to this issue long enough? If so, I would like to contact G66 for exchange of my device as well, with reference to your case, in order to avoid unnecessary discussions.

Thank you.

Regards,
Michael
 
Update me case:
G66 exchanged me AX8 for next "fourth-one", brand new unit - and all problems with squek disappeared.
Unit is new, serial number starts also with 17-03.

I want to praise cooperative from G66. In spite of the difficulty of finding the reason of the problem, they made did all to find positive conclusion.
 
Gday,
I had a digital desk that was whisper quiet - one day it started whining (in a similar manner to what you have described) with no aparent reason. After lots and lots of digging, I found it to be the led dimmer circuit - when you dimmed the LEDs in the desk, it would whine....does the ax8 have a way to adjust the led brightness? If so, adjust them to as bright as possible, and see what happens to the whine.
Thanks
Pauly
 
glombi said:
@SaBer

Could you please confirm that the exchange of your AX8 to a 2017 model really solved the issue for you, after you had the change to restore/test all settings and configurations thigt might contribute to this issue long enough? If so, I would like to contact G66 for exchange of my device as well, with reference to your case, in order to avoid unnecessary discussions.

Thank you.

Regards,
Michael
Click to expand...

Yes, I tested things now thoroughly, and with the similar setup as before (two FET boosts maxed out), and there's no correlation with LED activity and noise level. I made a similar spectrum analysis, and now I'm seeing an about 6 dB spike around 3 kHz, which is totally ok, given the noise floor is very low.
 
glombi said:
Nope, only display contrast can be adjusted. But internally they maybe PWM though...
Click to expand...
Since there's 27 footswitch LEDs in total, I'm assuming there could be some level of multiplexing going on also. In some videos, you can clearly see the amp control LEDs sort of "sweep", but I've never seen the footswitch LEDs do it on any video.
 
I have to chime in again here, and praise G66 for their customer service. It really has been top notch.

I have also received a replacement unit and so far there hasn't been any noise issues. G66 was really helpful and service minded through the whole process, so nothing but good words to G66 from me!
 
E-Sound said:
I have to chime in again here, and praise G66 for their customer service. It really has been top notch.
I have also received a replacement unit and so far there hasn't been any noise issues. G66 was really helpful and service minded through the whole process, so nothing but good words to G66 from me!
Click to expand...

+1

Same for me. G66 service is absolutely kind, supportive, fair and quick. Got mine exchanged in no time and no more noise level issue so far. Thank you Jaques :)...

Obviously the transfer of assembly to China was a good step, at least I don't mind...

Unfortunately I'm left with two concerns regarding the quality/reliability of the unit itself:

1. Since the beginning and still still after the exchange I have a kind of zipper noise when i rock the wah pedal back and forth (not when the wah is activated and pedal position is unchanged!). I use wah a lot for clean funk sounds, so this is annoying.

2. When I wanted to upload presets to the exchanged AX8, I got "communication timeouts" every time. Which I never experienced before with the old unit!. The problem persisted after several reboots of my MacBookPro and/or the AX8 and even with 4 different USB cables from long, to normal to short. I was about to return this unit again. Luckily I gave it another try and installed AX-Edit on another iMac. With that I could upload presest again and again without any issues. When I went back to the MacBookPro I also never had a timeout again (just to be shure I uploade the 8.02 presets several times), even with 5m USB cable. So I'm fine rigt now. But it always makes me nervous if an issue disappears for no apparent reason, because I'm never shure that it won't return in the most unfavourable situation...
 
glombi said:
+1

Same for me. G66 service is absolutely kind, supportive, fair and quick. Got mine exchanged in no time and no more noise level issue so far. Thank you Jaques :)...

Obviously the transfer of assembly to China was a good step, at least I don't mind...

Unfortunately I'm left with two concerns regarding the quality/reliability of the unit itself:

1. Since the beginning and still still after the exchange I have a kind of zipper noise when i rock the wah pedal back and forth (not when the wah is activated and pedal position is unchanged!). I use wah a lot for clean funk sounds, so this is annoying.

2. When I wanted to upload presets to the exchanged AX8, I got "communication timeouts" every time. Which I never experienced before with the old unit!. The problem persisted after several reboots of my MacBookPro and/or the AX8 and even with 4 different USB cables from long, to normal to short. I was about to return this unit again. Luckily I gave it another try and installed AX-Edit on another iMac. With that I could upload presest again and again without any issues. When I went back to the MacBookPro I also never had a timeout again (just to be shure I uploade the 8.02 presets several times), even with 5m USB cable. So I'm fine rigt now. But it always makes me nervous if an issue disappears for no apparent reason, because I'm never shure that it won't return in the most unfavourable situation...
Click to expand...

First issue sounds like a mechanical issue from the pedal itself. If not try different cables and/or inputs. Also try putting the wah at a different spot in your signal chain.

The second issue just sounds like a corrupt install or file. That's not really AX8 issue or its software. It can happen though I agree it is annoying and can be frustrating if not caught right away. I hope all is good for you now.
 
BigRalphN said:
First issue sounds like a mechanical issue from the pedal itself. If not try different cables and/or inputs. Also try putting the wah at a different spot in your signal chain.
Click to expand...

I tried 3 different expression pedals (Mission, BOSS and another one), 4 cables (DIY and from G66) and several original presets as well as custom presets with only wah, amp, cab. Same problem all the time...

BigRalphN said:
The second issue just sounds like a corrupt install or file. That's not really AX8 issue or its software. It can happen though I agree it is annoying and can be frustrating if not caught right away. I hope all is good for you now.
Click to expand...

The funny thing here is, I did not even re-install on my MacBook Pro. Seems like the USB-line was "blown through" by the iMac...
 
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