Genos Aux In - Hissing Noise

[fischnek]

Hi,
please tell me if this phenomenon is normal:
When I plug a cable into the aux in L/R input of the Genos, I start to get a hissing sound from the speakers, like white noise.
If I put some sound source at the end of the cable, the hissing becomes weaker, but it persists until the sound of the sound source can be heard.
I haven't used the aux in for a while, but I'm almost certain that this wasn't the case in the old days.
Any similar experiences?
What could be wrong?

thanks

fis


Edit: Topic title modified by overover

[overover]

Hi Fis,

When no cable is connected to the Aux In jacks these inputs are automatically muted.

When you connect cables there, but with no sound source on the other end, this will of course cause some (unwanted) noise.

Before connecting cables to the Aux In jacks, make sure that the Aux In Volume control is turned down to zero in Mixer display (Panel 2 page).

Set the output volume of the external audio device as loud as possible and only turn up the Genos Aux In volume as much as necessary. This way there should be no problem of unwanted noise.


Hope this helps!

Best regards,
Chris

[RayClem]

Sometimes noise can be caused by improper grounding or ground loops. To avoid this issue, make sure the same AC power circuit is supplying power to all devices. Sometimes that is not possible.

Depending upon the audio source, you might need a DI box to minimize noise.

[MadrasGiaguari]

I have an Hammond module permanently connected to Aux In, controlled via Midi.

The module is usually off. I always (both when On or Off) keep the module volume at 3/4, which is well balanced with Genos sounds.

When I want the Hammond sound, I just turn the module On.

Never had any noise of any kind.

Just to give a knowledge contribution.

Ciao,

Angelo

[fischnek]

Thank you for your valuable comments. I think there is a mistake here. The noise level is much stronger than the input signal level. So you cannot use the input without the noise being audible.

If I understand correctly, aux-in can only be controlled in the mixer, so there is no slider or rotary assigned by default. And there's no effect, so it's not like some distorted effect is adding the noise.

I think I need to start a warranty claim on this. I can't find a similar error description anywhere on the net.

[RayClem]

What specific device are you connecting to the Aux Input?

This is designed to be used with a line level input. The input device has to have a built-in preamp.

If the device does not have a preamp, then you need to use the microphone jack input.

[fischnek]

that's just it. The noise comes as soon as I plug a cable into the input. with nothing at the other end of the cable. It doesn't matter if it's a symmetrical or asymmetrical cable.
And this noise is not the usual hum that you get usually at this time. It's a perfect white noise. It's like when your radio is playing on a frequency where there's no broadcast.
As a signal source, I've tried everything from electro-acoustic guitars to mp3 players: same thing.

[overover]

Hi Fis,

Based on your description, it actually sounds like a hardware defect (possibly a defect in an input IC (OP Amp) at the AUX IN.)

Does the "white noise" also occur when connecting a cable when the AUX IN volume in the Mixer is turned all the way down?

Are all other inputs that are not currently needed turned all the way down (MIC, USB, Bluetooth, WLAN)?

By the way, except for the MIC input, all inputs and outputs of the Genos2 are unbalanced. Therefore, please only use unbalanced cables (TS plugs at the Genos2 end, no TRS plugs).

If everything is working normally, no increased noise should occur when connecting a TS plug to the AUX IN L/L+R jack (or when connecting two plugs to both AUX IN jacks).

However, note that the signal fed in must have a certain minimum volume. If the output volume of the external device connected to AUX IN is too low, it may happen that the sound input is interrupted. In this case, increase the output volume of the external device.


Best regards,
Chris

[fischnek]

Thanks for your reply, overover.

The noise only occurs when the aux is enabled in the mixer and when the aux volume is on. The amount of noise increases as the volume is increased, but it is stronger than the input signal itself, so it "masks" the music signal (Mp3 player, phone, electroacoustic guitar, another keyboard was used for testing).
It's pretty bad.
I will write to the shop where I bought the instrument.

[overover]

Thanks for your reply, overover.

The noise only occurs when the aux is enabled in the mixer and when the aux volume is on. The amount of noise increases as the volume is increased, but it is stronger than the input signal itself, so it "masks" the music signal (Mp3 player, phone, electroacoustic guitar, another keyboard was used for testing).
It's pretty bad.
I will write to the shop where I bought the instrument.

Thank you for your detailed feedback, Fis!

Based on your description, I think it is very likely that there is an internal hardware defect on the Genos2.


Best regards,
Chris