in line AC hum filter for noise from the house?

[Jimbilly]

I'm getting some noise through my amp at the church I play at, like a really high pitched morse code, even with nothing plugged into the amp input. My amps don't make this sound at home.  Just loud enough to be annoying. 

 Are the in line filters any good? like the Ebtec hum x?

 

https://www.sweetwater.com/store/detail/HumX--ebtech-hum-by-ground-loop-hum-exterminator/reviews

[BoogieMKIIA]

Morse code? Sounds like cell phone interference or other wireless source. Check if there is a phone on or near your amp. Not likely that the device you found will help, but could try it in case the noise is coupled to the church AC power. 

[HSB0531]

I'm glad this came up because I have problems with AC hum in some older buildings and I didn't know Morley had this product.  I didn't want to buy a heavy and expensive power strip/conditioner, and this item may solve my problem.

As BoogieMKIIA said, the Morse code sounds like it's cell phone or other digital (WiFi) interference.  That would transmit over the air and can interfere with some IC's (if it's a hybrid or all solid state amp) , and I don't think an AC line filter will solve the problem but, it would still be a very useful tool worth getting.

 

 

[Jimbilly]

My phone is not kept nearby, but I bet the people up in the sound/lighting/tech booth have their phones next to the mixer board, so that is a good clue!

[HSB0531]

1 hour ago, Jimbilly said:

My phone is not kept nearby, but I bet the people up in the sound/lighting/tech booth have their phones next to the mixer board, so that is a good clue!

That digital "Morse code" sound that was mentioned was something we ran into at a recent sound system service.  It came through the sound system and it turned out to be the adapter cable going from a new Galaxy S phone to the inputs on the digital console.  I swapped out the fancy Y cable with another one and the noise went away.

Also: leaving a Sony Digital Walkman on top of electronic gear will cause noise in the audio.  That happened to mean a while ago when I did just that.

I moved the player away from the preamp and the noise went away.

[HSB0531]

1 hour ago, Jimbilly said:

My phone is not kept nearby, but I bet the people up in the sound/lighting/tech booth have their phones next to the mixer board, so that is a good clue!

Are you going through in-ears or wedge monitors?  It's possible that if you are, the noise is coming from the monitors and it's starting at the FOH console from phones/ digital players plugged into the console.

[Jimbilly]

48 minutes ago, HSB0531 said:

Are you going through in-ears or wedge monitors?  It's possible that if you are, the noise is coming from the monitors and it's starting at the FOH console from phones/ digital players plugged into the console.

wired in-ears, from Presonus individual monitor mixers connected by cat5 (I think, or similar to cat5).  I thought it was maybe from my effects, but the newest clue is that my little Univox amp idling on stage with nothing plugged into it makes that sound all by itself, but not at home.  I will mention to the sounds guys that phones might be causing some noises.

[HSB0531]

See if they're running CAT5e or Cat6 STP cable. The STP stands for Shielded Twisted Pair, and it's recognizable by a metal shield around the plugs. These cables are much more immune to outside interference and can run longer distances without dropouts or other problems.  And, it could also be old electrolytic power supply caps not filtering the power coming into the amp.  Digital interference can also get through the power lines and into the audio gear that way.

 

[Jimbilly]

1 hour ago, HSB0531 said:

See if they're running CAT5e or Cat6 STP cable. The STP stands for Shielded Twisted Pair, and it's recognizable by a metal shield around the plugs. These cables are much more immune to outside interference and can run longer distances without dropouts or other problems.  And, it could also be old electrolytic power supply caps not filtering the power coming into the amp.  Digital interference can also get through the power lines and into the audio gear that way.

 

good stuff!  thanks!