Buzzing sound even with Noise Gate - HELP

Quad Cortex
1

Hi.

I own a Quad Cortex for about one week (bought it from Thomann).

It was one of my dreams: getting to work with such a powerhouse, state of the art equipment. I’ve used your plugins before with zero complaints (actually, I only have nice things to say).

But unfortunately, until now, my experience has been quite troublesome.

Before practicing or gigging with the unit, I tried to get to know how it works at home. I plugged the power adapter, then my iem’s to the headphone out.

Then the noise started.

An electrical, intermitent buzz, that slightly improved when touching the guitar strings, knobs, or the quad cortex itself.

I searched for possible solutions online and found a lot of people complaining about the lack of grounding of the power supply. I also read this: Resolving Noise Problems

Then I read some suggestions that stated that the quad cortex needed to be connected to other equipments to ground itself. The only equipment I could try this on was my laptop.

I connected both equipments and there was a slight improvement.

This time, every amplifier (both clean or distortion) was still unusable without a noise gate, but I managed to only use one (the input noise gate).

Although usable, playing a chord and letting it “die” before muting the strings causes noticeable buzzing.

I will try to record what is happening as soon as possible, but I have found a user online with the exact same problem here.

https://www.reddit.com/r/NeuralDSP/s/72jQeoGcxB

I asked if he succeded in getting it to work, and sadly he said that he returned the unit.

I honestly don’t know what to do.

I really want to be able to play and enjoy the Quad Cortex. I don’t want to return it.

But at 1699€, it should give me more sound quality, less noise and more reliability than my previous equipment: a 400€ Boss Katana (which is plug and play and never gave me buzzing or any problem whatsoever).

Thank you for all your help.

2

I’ve also had noise issues when using the headphones. Do you have studio monitors to test this with? When I moved out and changed from headpones to monitors all noise went away, making me believe that the headphones I was using are shitty.

3

I’ve tried different headphones. I think it must be something Electricity-related.

4

I made some tests at home.Using only headphones, it is impossible to work with:

Then I went to our band studio, where we rehearse.

I recorded 3 samples with the following setup:

1. Quad Cortex without any cables connected, except power supply, guitar cable and headphones

2. Quad Cortex with a XLR cable from output 1 to a Mixer and all of the above

3. The same as 2 but with Noise Gate 50%

You can find it here:

https://drive.google.com/drive/u/1/folders/14GP_ADA6CiD95QxRbuMlPplqP7CmNAP6

What I’ve found is that there is huge electrical noise, without grounding being provided by another equipment. This is coherent with what Neural DSP says on their website:

If the Quad Cortex is used with headphones (without any other equipment connected), some instruments’ pickup interference can modulate QC’s ground/earth line, which will result in perceived hum. This is particularly true with passive, single-coil pickups.

However, it is possible to provide a ground/earth connection to the Quad Cortex by connecting another piece of equipment to remove/reduce this noise. This can easily be done by using any of the inputs or outputs found on the rear of the QC and said external equipment does not need to be powered for it to provide the reference needed to eliminate interference.

Following my previous tests, connecting the XLR to a Mixer provided the best results, eliminating almost all of the electric buzzing. So, I have a few questions for the community:

  • Most of the time (if not always), rehearsing or playing live, the Quad Cortex will be outputting via XLR. So, is it safe to consider that most of the time, it will be able to achieve that type of low noise, correct? Does your unit behaves the same way?- When I’m at home, what do you recommend dealing with the buzzing / electrical noise? Should I try buy a Hum remover? Does it work? Should I try to buy an isolated power supply in order to try to, at least, ground the equipment in a more efficient way? I’m trying to avoid buying a Cioks DC7, because I don’t need the extra outputs…

I don’t have more musical equipment at home, such as amplifiers or mixers, so I will need to find something to provide me the best sound possible whenever I’m in that type of environment.

Thanks for your patience and help.

P.S. I’ve been in touch with Neural DSP’s support.