Help - noise

Hi Brian, guys,

something strange is happening.

I’ve traveled to berlin for a show and just turned on my system to prepare it. I brought a Pittsburgh Modular Outs so I can monitor the system via headphones on my hotel room.

When I connect a signal (not from the ER301) to my addac 802 mixer and from there to the Pitts Outs the signal is clean and I listen to it on my headphones.

When I take an output from the ER301 it adds a lot of noise, even with no signal coming out of the ER301. The noise is still present even with the volume knob turned down and even if i just connect the ER301 to the addac mixer without raising the gain. It gets a bit worst if I connect the ER301 directly to the Pitts Outs.

I turned the system on and off several times and tried the ER301 on its blank state and on a quicksave state. When I load a quicksave I hear a noise corresponding to the blinking lights. This is kind of strange because it only happens when the ER301 is involved.

Any idea what this could be? I’m in panic because my show is tomorrow.

using the latest stable firmware.

Noisy mains power supply perhaps? Might be ok at the venue!

Also, sorry to ask, but 9/10 whenever I have a noise problem it’s a damn cable, either patch or power - the power one took me a while to track down - ugh!!

I don’t have much to add beyond these obvious things, but hope it works out for you ok!

Good luck!

Does your case have more than one power supply? This can happen if you have multiple power sources that aren’t all grounded together.

For instance, I was experiencing an identical noise issue with the 301 last night (noise when lights were active or files were loading). I was using modules from 3 cases. I had case 2 plugged into case 1, and case 3 (with the 301) plugged into case 1. I added a random cable from case 3 to case 2, and the noise issue went away immediately. Sometimes I need to connect two cables for it to go away.

The 301 also gives you the choice of whether or not to use +5V with a jumper on the back. More on that here: Power draw of the ER-301

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it has neves happened before @anon83620728 so I don’t think it is the power supply.

it doesn’t seem to be a cable because if i unplug all cables from the ER301 the noise continues. I have changed the output cable, of course.

Only one case (MDLR case) with one power supply. Meanwell RT65B. : /

thanks for helping out guys

No I mean the actual power coming out of the wall socket is noisy!

The only thing that’s changed is your location, that’s prime candidate!

Is there a fridge on somewhere on the same circuit? My friend had terrible trouble with his fridge and his audio system to the point that if he was going to listen to music he would unplug his fridge!

oh ok!

yes… I’m crossing my fingers for that to be the problem… but is that is the case its also weird. Ist the Er301 that sensible and susceptible to noise issues? that can be a problem for a touring musician.

I’ll try different wall sockets!

Heh - you would hope venues have a reasonably clean power supply, I wouldn’t really expect that t be true in an old building in Kreuzberg!

No idea about ER-301 susceptibility to this kind of problem, but in fairness, it’s not really the job of your sound computer to clean up dirty mains power :smiley:

I went with Furman power conditioners because I couldn’t for the life of me get clean audio on my Adam A7x monitors. On my previous monitors I never noticed the hum. Different setups require solutions that might not at first be apparent.

ahah. yep… I’m in Neukoln which is basically the same…

Fingers crossed for the venue to have a normal power supply.

I don’t understand much about electricity in general but is it normal that the ER301 is susceptible and the other modules don’t?

Here’s the setup I’m using:

could this be related with the pitts outs? I connected the headphones directly to the ADDAC mixer output and directly to the ER301 and that ugly noise seems to goes away…

but then again. only the ER301 induces noise to the pitts outs!

edit: maybe the noise isn’t amplified… but can still be there…

It’s possible. In the noise scenario I mentioned above, I was connecting the ER-301 to a Pittsburgh Outs.

so i did a test…

I connected out 1 and 2 to the inputs 3 and 4 and recorded some stuff on the built-in recorder to test if the noise was coming out of the module. Then I transfered the file to the computer to listen to it and there was no noise… so it’s definitely some ground issue or whatever with the Pitts Outs I guess… At least the ER301 is not broken.

Any explanation for this behaviour anyone? :stuck_out_tongue:

I had the LEDs on the Batumi bleed into the audio on my Pittsburgh mixer. Relocating the Batumi away from it cleared it right up. Doesn’t seem super-likely in this case since you were getting the noise with one specific module, but you might see if moving modules helps.

I’ve also had strange noise that clears up when placing modules at a different location on the power bus (moved from flying bus
to fixed). Again not super-likely, but maybe worth evaluating.

final update: the show went ok, and with no noise. However the Pittsburgh Outs wasn’t used. I also tested the module on the venue and it was still terribly noisy, but only with the ER301 connected to it…

So, unless my Pitts Outs is malfunctioning, ER301 users should avoid it.

I will try to get my hands on a Pitts Out but if you have a voltmeter I would like to know the result of the following measurement:

  1. Plug a patch cable into one of the outs on the ER-301 (or any module) and then plug another (different) patch cable into the input of the Pitts Out.
  2. Measure the voltage from the sleeve of the “output” patch cable (put black probe here) to the sleeve of the “input” patch cable (put red probe here).

Sure. I don’t have a voltmeter but I’ll try to find one to do this! Happy to help.