Mod Duo X noise when using microphone

I hadn’t had too much problems with noise coming from my Mod Duo X, but I have mostly been using hot line levels going into it, and gating out lower levels. Now I want to plug a microphone directly into the mod which means boosting that input, which reveals a constant pulse/noise coming from the power supply (as far as I can tell).

I boost the hardware inputs by 12 DB, and then the first plug-in I use is a gate/compressor to bring this level up to a usable audible signal. Without making any sound into the microphone, there is a clicking/pulse going on, which sounds like USB type noise.

Here are some key things about this phenomenon:

  1. When using the level meter plug-in, I can detect a -24db click, pre-compressor.
  2. If I delete a plugin from the web-gui, it produces this exact click, so I can reproduce this.
  3. If I remove USB from the unit, the steady click still exists, so it’s not just a USB/web-gui issue.
  4. If I touch/wiggle the power cable going into the unit, it generates and alters the clicks, as if there is a faulty connection or something, but power doesn’t flicker or anything.

I’m wondering if USB noise is getting into the power signal?
I do use a power conditioner.

And just to really limit the usual suspects. I removed the microphone from the input, so nothing is going into the MDX, and removed the USB connection, and the pulse continues.

I turned off the computer, and everything plugged in which might be adding a pulse to the power - even turned off the lights. There is just my MDX in a dark room, lights flickering to a steady pulse coming from where exactly?

More information here:

I have the MDX set up, with nothing in the input, and there is still the regular pulse of noise. When I use the Settings menu, and scroll past Tuner, it generates this same noise. It doesn’t matter if the tuner is muted or not - going to that item, or moving off of that item will generate the click. Scrolling past the other items in the Settings menu doesn’t do this.

I took an extra power cable and cut the ground to see if this would affect this, even though my situation does not sound like ground hum at all, it is related to the power. Cutting the ground pin did not make any difference.

Is this just a dying power supply? It’s the MOd branded one which came with the unit.

I purchased a new power supply because my belief was that the original one was dying. However the issue still persists with the new power supply.

This has kind of rendered my Mod Duo X unusable for my current needs. Is there any way to escalate this to see if there is a bug in the most recent update?

Hey mate,

I have an MDX and can check if I am experiencing the same thing. I am also experiencing strange behavior in menus, but haven’t noticed anything audible yet.

Can you post this over in the bug reporting area?

You can crosspost this thread with the bug report.

Sorry you havent had any responses, most of the MOD team take their well earned weekends. I have no doubt that you will have someone from the team checking in with you tomorrow.

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I’ve put this in the bug report area - didn’t know that existed separately, so thanks for the info!

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The mod manual indicates that you can use microphone level input, which for me does not seem to be workable. Are there any Mod users out there who do run a microphone into the MDX? Or are people mostly raising the mic gain before going into the device, and running the device at line level and not boosting the input?

I am using a Shure 57B dynamic mic hooked up to a lo-z to Hi-z xlr-trs transformer. It was about 15 bucks at a local store.

I have the input boosted with a 3db gain, and it works perfect. Iirc, my mic could not get enough gain without the transformer.

Before I had used a secondary interface with phantom power for my cardioid mic.

Edit:

They have confirmed the bug report that I submitted a bit before yours, so they are actively working on the reports.

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Thanks for the feedback. I hadn’t been using a lo-z to hi-z converter initially, but now I am and this seems to allow me to leave the input boost at 6db and get a healthy signal. I can boost it within plug-ins after that, and gate out any noise. But if I set the hardware inputs to +12, there is internal noise which seems related to processing, switching menus, things like that.

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I struggled with noise coming out of my units at first.

I did swap to a groundless psu which helped a lot, and the built in noise gate seems to improve audio considerably.

Is your dwarf connected to a mixer by chance? Some of my noise was coming from gain staging issues within my mixer.

My input gains are usually ± 3dB depending on whats being input, and I shoot for yellow indicators both in and out. I’d recommend dropping your input gain down considerably and adjusting the gain at another stage in your audio path.

My MDX is hooked up with USB and connected to a powered hub, and my output gain for MDX is at 0db. I generally make the adjustments for gain at my interface rather than on the unit itself.

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So I am using a grounded psu, but have a groundless one which didn’t make any difference. My noise is not like ground-hum type, but like USB traffic noise - if that makes sense.

I’m using the Mod Duo X, and my mixer is fine, there is noise even when the USB is not connected, so I think the noise is from internal processes.

I have been experimenting with the noise gate and the compressor in the Settings menu, but they don’t really work well. I set up a gate plug-in, and compressor plug-in, which I then adjusted to get the results I wanted. Then I disabled those and tried to use the internal noise gate + compressor and the results were bad. The internal noise gate seems to always click when kicking in (or out). I find that to avoid clicks I have to set it so low - that noise is barely gated. But using a gate and compressor plug-in, I can get reasonable results.

This makes me wonder if the internal noise gate and compressor use less CPU, or if there is any advantage to them, other than they can be global.

I know you tried a different power supply already. But for me, all the noise issues were gone, after I started using a Digitakt Power supply.

@S_Righteous do you have your display brightness levels in something different than 0 or 100?

My display brightness is 50% and display contrast 47%. I think that is how the unit shipped as I don’t think I ever knew I could customize those settings.

The controls for that have been added some releases ago.
Can you try to change them and listen if they affect the noise? Especially the brightness, what happens if you put it either to 0% or 100%?

I’ve adjusted the brightness and I am not getting as much pop sounds but just high noisefloor when the inputs are set to +12db. I’m not certain why I’m not getting the amount of usb noise I had been.

Two things I can confirm. If you scroll past the Tuner in the menu, all noise stops, it is dead quiet.
Also, when you raise the input volume, there are pops when you hit +4db and +12db as if those are some kind of thresholds or something. The pops you hear when you scroll past +4db are what I was having frequently, but now cannot reproduce.

Also, I had been getting those pops whenever I deleted a plug-in from the web gui, but that isn’t happening now.

That’s expected. It’s rare for the setup where +12dB will not raise the noise floor to an audible level. If you are feeling the need to have the input gain set to +12dB I would suggest you take a look at the other gain stages on your setup so you can lower that.

This one is indeed quite odd and I’m not sure if I fully got it.
Do you mean when in the settings menu when you cross the Tuner the unit gets quiet? Is that just when you are over the Tuner and therefore with the tuner opened? Or simply when you cross by it?
If the first, do have the Mute for the tuner active?

You mean the input gain right? At some point was labeled as Input volume, but that was not accurate and we changed it. If you still see it as input volume, please update your device.
Those pops are expected just when you hit that level since indeed it crosses certain thresholds.

So does that mean that you can’t reproduce any of the issues anymore? Have you updated your unit?

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