I was unable to resolve noise in the Mod Dwarf after trying DI and groundless power

Hi there,

Gone from one type of noise to another. At the following link you can hear the difference between the MOD PSU noise and the Ledkia PSU noise.

Maybe in real world use the Ledkia is less noticeable because it doesn’t have the constant whine of the MOD devices PSU but either way, I’m always less impressed with the device for the amount of these problems that are going on.

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How is the Ledkia PSU? Can you send a link?

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Hey,

36W 12V 3A, isolation class II

Here’s the link

I hope this helps

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Are you using a MOD Dwarf? If yes have you tried the ground loop compensation feature? Try it, especially with this power supply.
Let us know how does that works.

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I have struggled with this type of issue for ages.

I got really close to getting it handled. Every time I readjust my instrument set up, it’s the same troubleshooting procedure each time.

I’ve solved for ground loops, spent more than a grand on a solution. Still sent it all back.

I had a lot of success with a groundless power supply. In fact, the results from adding DI’s, stage bug, ground lifters, an isolation transformer, and even isolated psu’s, didn’t come anywhere close to achieving the same thing a 13 dollar PSU did.

I changed my set up again, reconfigured everything, threw in a massive power conditioner, and the noise is back.

I know there is something in my setup causing an issue. However, if I don’t use a mod device, the issue goes away.

I haven’t figured out what’s going on, why it changes during my gear refresh (even after accounting for the new variables), or if it is actually MOD related.

The noise seems to be hit or miss for people. I know I get noise from my dwarf far more than from my MDX, I even use the same power supply.

The noise gate stuff can be useful, but the ground loop compensator did absolutely nothing for the issue.

Looking at my dwarf unit, I have the kickstarter branding on the underside, even though I paid full price through reverb. So my dwarf is probably refurb, and the noise issue may be related to that.

I took a B-stock MDX at “full” price (aka accepted a plugin coupon) and the unit is far cleaner audiowise than my dwarf is, but seems to be sensitive to my other powered gear.

I’m a synth person if that helps, my gear is already powered and produces Line Level audio, and I’ve come to terms with the fact that my gain staging needs special attention.

You aren’t the only person with the issue you are facing, but mine is non critical because I am no longer recording or posting online for a while.

For others, like yourself, this is a far more critical thing to address imo

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Hi @kevplaysbass,

It helps if you describe in full your setup as it was when you recorded this. What is connected to what? What is the full signal path? What’s the full electric path? Any amps along the way? Is the Dwarf connected via USB to the computer?

(Devices connected to a computer via TS/TRS and USB at the same time are highly prone to noise, I get a lot of that with my Boss GP10.)

From the sound of the Ledkia, it seems to be a ground loop.

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I reached out to support. I was able to try a few different groundless adaptors and other sources of power. Can confirm that I was not able to eliminate the noise.

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Hi Mark,

Thanks for getting in touch. As mentioned in a previous post we’re currently using the MOD to process vocals.

  • Shure Beta87 goes to channel 2 of our Clarett+ 8pre (live monitoring muted) because it needs phantom power.

  • Line output 3 sends the mic signal into the MOD with a balanced cable. MOD input gain 0dB.

  • Both outputs of the Dwarf send at 0dB to inputs 7 and 8 on the Clarett+ with balanced cables. Direct monitoring enabled on channels 7/8.

  • Both the Clarett+ and the MOD are powered from a Furman P-1400 AR E.

USB not connected, and in response to @jon can confirm that I’ve tried the Ground Loop Compensation feature of the Dwarf and it makes no difference at all

Let me know if you need any more information than that.

Kind regards,

Kevin

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Good :slight_smile: So I’m talking with you over there :slight_smile:

Ok. So let’s follow up there. But still, I believe that the issue is solvable and your unit is not faulty. Anywya, let’s keep investigating.

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No, it’s not. At that point we were only producing that back plate and due to pressure for a short while we shipped that even to sales. We don’t do it anymore. That was your case.

This is actually really curious. From my personal experience, I tend to find noise issues way more often with the MOD DuoX that I have than with the MOD Dwarf. Anyway, up to now, every time that I found it in any setup I managed to solve it.

This is really unfortunate. Most likely what is happening, in this case, is that the new device that you are putting on your setup is somehow uncovering the noise issue that you managed to cover before.
I would say that you have a couple of generic things to test and these ones are true to test on the MOD Dwarf or on the new piece of gear:

  • power supply of the device
  • balanced cables on the output of that device
  • Passive DI on the output of the device
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I believe that here you have a potential source for a ground loop between the power of the Clarett and the MOD Dwarf.

Yep, especially if you are somehow using the Dwarf in a sort of FX Loop on the Clarett.

Have you experimented with the power of both devices?
Try to connect it to different wall sockets and also to the same in a power strip.

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Thanks for the detailed info, @kevplaysbass. Lots to go through here.

Starting from the end, you have a “badass” Furman power unit. It has a steady 40dB filter at 100 Hz, which should reduce hum significantly (even if not ever entirely.) It has other fixed filters at other frequencies as well.

The bad news is: transformers are almost always the culprit when it comes to noise (specially hum), and if your Furman sits close to the Focusrite or its PSU, you might get some induction due to the fact that the transformers inside the Furman and not metal encased. Their top units (like yours) have massive toroidal transformers wrapped in tape and metal film, but the ideal is to have a ferrite encasing for the transformer. That is very expensive and even audiophile companies instead build their amps with the EI-type transformers (the traditional ones) mounted on the outside, away from noise sensitive components.

This needlessly long intro is to say: test your setup without the Furman and/or place all PSUs away from it. See if it makes a difference. If your PSUs are already far from the Furman, you may skip this one.

Second, you are most likely creating a ground loop yourself by cycling the microphone into the Clarett twice. That’s because the ground connection will then have two clear paths back to earth: one is departing the Clarett+ immediately, and the other is looping through that cable. The only solution there would be to have some preamp provide Phantom Power before the Dwarf, then from the Dwarf to your interface. Which then brings us to 3.

Third, Dwarf’s inputs are not balanced, even if the connector is TRS. Check this info here:

image

Therefore, your microphone might be coming in too hot.

So, to be scientific about your noise problem, here’s what you could do. Always use more than one audio cable for the same connection, to rule out shielding or cold solder issues.

  1. Test your Dwarf standalone: play your bass into the Dwarf and listen to it with good headphones. No need for a 2000K Euro mega hyper ultra studio grade stuff, a good €100 one should do it (like a Sennheiser HD280.) Just avoid earbuds – unless of course is an Ultimate Ears or another big shot. And do that in two or more different locations, to rule out RMI or EFI at your home/studio. I live in northern Italy too and RMI/EFI is as voluminous as the price we pay for electrical power… (actually I was in your 'hood not too long ago, and topped-off in Slovenia because it was much cheaper! :wink: )

If you get noise similar to your audio files on test #1, then you might have a faulty unit. Contact support@moddevices.com directly in that case. Otherwise, keep going.

  1. Try the following setup, assuming your Clarett+ 8 Pre has line leval outs (their website says so): Mic => Clarett+ => line/unbalanced output into Dwarf => Headphones. If you get noise there, then the sources is your Focusrite unit. Your Shure mic can take as little as 12V DC phantom power, so if you can regulate that instead of throwing a full 48V, that could have some positive impact.

  2. Try the same setup above BUT with the Clarett+ connected to your computer. If noise starts there, then your issue is the USB connection.

  3. Finally, do as you did previously, with the looped microhpone. If noise starts there, your problem is somewhat solved: either employ a dynamic microphone or use some preamp ahead of the MOD for Phantom Power.

Now, Focusrite is known to have a somewhat troubled phantom power circuitry, so if you have another interface at your disposal, try that too.

Lastly, power conditioners are not mere power strips. They need some load to work effectively, and given the power of your unit, I’d say some good 1.5 or 2 amps to begin with. If you have just one or two PSUs and less than that plugged in, you’re actually overheating your Furman and that brings more noise to the picture.

Good luck.

(Disclaimer: I do not work for MOD Devices and my opinion is merely technical. If you suspect you have a faulty unit, please contact them directly.)

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Hi @QuestionMarc,

First of all, many thanks for the epically comprehensive answer. If you find yourself passing through Trieste again, please give me a shout and I’d be delighted to offer you a beer, spritz, coffee or whatever you like!

I’ll run through all of your suggestions this evening and look forward to drawing some conclusions, finally. Actually, I’m feeling somewhat silly that I missed the fact that the Dwarf inputs aren’t balanced.

In regards to the load on the Furman, at home we run our whole setup off it which includes our laptop which is connected to the Clarett+ (important detail that I left out there, sorry) and a pair of Yamaha HS7s. For small gigs where we’re running our own sound, the only difference in our setup is that we’re using two AccuGroove MiniGroove cabinets as PA which also run off the back of the Furman. Once they’re running at gig volume, the whole rig is drawing roughly 1.5A if I remember correctly. At home, the current draw is certainly going to be lower than that…

EDIT: @QuestionMarc, sorry, some more details. Regarding the Furman creating interference with the Focusrite, actually without the MOD plugged in I can crank the Clarett+ master to maximum with the HS7s and I can only just about audibly hear a hiss but there’s no other interference going on. We have a 4U rack that has the Furman in the top slot, the Focusrite in the second slot, a blank, and then a preamp for the bass in the bottom slot. The only thing that has been introducing noise into the equation so far is the MOD. The MOD is powered off a rack-mounted extension sockets on the back of the rack-case which itself is plugged into the Furman, as is a laptop, but the MOD presets are all done and we don’t leave it connected via USB to the laptop because that certainly is a recipe for noise problems.

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holy mackerel, I’ve read that wrong at least three times. I kept reading that as “balanced”. D’oh!

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Ayy let’s go, the device works great itself, I was confused when I saw kickstarter branding and had thought it was most likely a factory refurbished. Cool that it isn’t!

That’s actually interesting, I had the opposite problem, however, I may actually try it out and see
if that is the case and I’m misremembering.

I’ve done all this and it didn’t improve. I use balanced cables already, swapped PSU’s, and I tried the DI stuff before. My initial findings were somewhat accurate in the fact that I have something else going on.

What’s strange is that on my mixer, the master track has audible noise that actually shows up on the level meter, but none of the individual tracks show any indication of what is causing it.

I think my Deepmind is a part of the problem, I’m gonna disconnect it out of my system, and make sure that I have zero ground loops. It was my first sunth purchase and it was relatively cheap for what it is.

The noise came back after I installed all of my synths into my set up, and I had a considerable amount of new introductions that I hadn’t worked with together.

I’m like 95% sure it’s not even MOD related because the audio is crystal clear if I directly hook my synths into the dwarf/MDX and run the output direct into the audio interface.

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Please bear in mind these tests are basically a step-by-step elimination process, only they kind of work backwards – you keep adding devices instead. I cannot tell at all where lies the fault, or even what it is. These days, with LED lamps that leak like there’s no tomorrow, several switching PSUs with no metal encasing around the house and a plethora of devices, simple as they might be (such a microwave), whose makers/vendors think it nice to put a LCD touchscreen on them, getting rid of electrical interference is getting nearly impossible. Equipment with high processing power outputting audio and/or video suffer the most. (Even CCTV needs substantial filtering these days.)

I gave you an approximate figure, the idea there is that if the load is too little, the system may end up running too hot at the source and this can actually produce more noise. That’s a “weird” feature, but power conditioners are sometimes like that. It’s like when you turn on the water heater with little water in the reservoir and end up up electric shocks around the house: too much power with little absorption (some engineers disagree with this assessment, though.)

Will do. :wink:

For a country that doesn’t grow a single coffee bean, Italy does an absolutely fantastic job at brewing them. There’s good coffee in many places, but Italy takes the gold medal. :medal_sports: :coffee:

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This may mean that the noise is being summed from multiple channels. In other words, comes from multiple devices.

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Well, this bit is very telling – specially regarding your power mains at home.

Still, try to see what you get from the Dwarf standalone. If those files you’ve sent were recorded with the setup as you described it, you probably need to check it isolated from other components.

The total load on your Furman is adequate.

Do you have isolating screw spacers in your rack? Without the Dwarf it doesn’t look like you need it, but if you’re getting a ground loop, then you might. Also, if you place your Dwarf on that blank 1U, make sure it has rubber feet.

Haha, don’t feel bad. In fact, mackerel translates into sgombro in Italian, a word that’s close to large-sized rubbish. So I went a full year without any, walking past it repeatedly at the grocery store until I had the brilliant idea of consulting a dictionary… :expressionless:

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That is objectively hilarious. Thanks for that :laughing:

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Hello,
im also having this noise issue. I’ve tried all of the above. Also, I’ve been in contact with support, and they no longer respond. It’s been about 2 weeks since i last heard from them.
My issue is not with a Dwarf, but a MOD DUO X.
I just want to return it at this point, and be done with this whole hassle. It’s been a huge time vampire, not to mention $$$ to have these sorts of issues.

I’d like a response from support with an authorization to return it.
Sorry to be the killjoy. I really wanted this to work out.

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