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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: Jens Palm Bacher on February 19, 2019, 02:42:48 pm

Title: Axient Digital guitar noise
Post by: Jens Palm Bacher on February 19, 2019, 02:42:48 pm
Do anyone else have experience with noise from guitar pickups when used with Axient Digital?
Sounds like some kind of white noise, that is dependent on tx power.
The noise goes away when changing to cable or Axient analogue.

Title: Re: Axient Digital guitar noise
Post by: Jason Glass on February 19, 2019, 04:50:42 pm
Do anyone else have experience with noise from guitar pickups when used with Axient Digital?
Sounds like some kind of white noise, that is dependent on tx power.
The noise goes away when changing to cable or Axient analogue.

Yes, this is a widely known issue with some piezo pickups and guitar preamps.  The AM component of the digital TX modulation leaks into the audio circuit through the guitar's electronics and demodulates as audio noise, which is faithfully passed along with the intended audio.  The most common solutions are to use minimum TX power and locate the pack as far as possible from the guitar, or replace the guitar pickups and/or preamp with better shielded or lower impedance hardware.
Title: Re: Axient Digital guitar noise
Post by: Jens Palm Bacher on February 20, 2019, 05:15:55 am
Yes, this is a widely known issue with some piezo pickups and guitar preamps.  The AM component of the digital TX modulation leaks into the audio circuit through the guitar's electronics and demodulates as audio noise, which is faithfully passed along with the intended audio.  The most common solutions are to use minimum TX power and locate the pack as far as possible from the guitar, or replace the guitar pickups and/or preamp with better shielded or lower impedance hardware.
Did you speak to Shure about it? It seems to be much more prominent in Axient Digital than Sennheiser 6000/9000.
Maybe the modulation scheme makes a difference, Axient is 16QAM, Sennheiser is Pi/4 QPSK...?