Charge Pump Noise - Pedal Order Dependent

[Dirty_Boogie]

I need the collective brain power of this fine forum please to help me solve this... I have two PedalPCB pedals - a Kliche Mini (Klon), and a Cetus (Victory Kraken). I'd like to think I build quality pedals, with clean soldering, and clean, minimal wiring. Both pedals use a charge pump to bump up the voltage to 18V. I'm using high quality charge pumps, and a high quality isolated 1-Spot TruTone isolated power supply. My problem is this...

If the Kliche is placed before the Cetus, the Cetus emits a high-pitched whine when on. This is regardless if the Kliche is on or off (probably because it's "always" on as a buffered bypass pedal). Switch the order of the pedals, and no whine from the Cetus. I've switched out the charge pumps (other 1044CPA's). Also, same problem if using 9V batteries, and not the 1-Spot power supply. Removed all other pedals for this test video:

And the gut shots:




Open to any and all suggestions! Thanks.

 

[SmithvsSmith4]

Do you have the ground connected to your output jack on the Cetus? That other ground terminal at the top looks unpopulated and I don't see any ground wire coming out of the jack in your build report.

 

[Dirty_Boogie]

Do you have the ground connected to your input jack on the Cetus? That other ground terminal at the top looks unpopulated and I don't see any ground wire coming out of the jack in your build report.

View attachment 44263

Thanks. Yes, ground wire connected on the input jack (bottom left). No need to ground the output jack at the top with a wire, as it's grounded directly to the enclosure. On the whole, I mostly don't ground the output jacks with an additional wire - more chance of introducing a ground loop. Verified ground continuity with a multimeter.

 

[Dirty_Boogie]

One other point to add… the two other Victory V1 pedals I’ve built (Jack and Cobbler), with very similar topologies to the Kraken, don’t have this problem with placement relative to the Kliche. The only difference being that I built them on vero, as opposed to a PCB.

 

[Robert]

The charge pumps are heterodyning.

I would try a higher frequency charge pump in one of them, the TC7660HEPA runs at 120kHz.

This could of course go either way... It could help, or make the problem worse, but it's worth a shot.

 

[Dirty_Boogie]

The charge pumps are heterodyning.

I would try a higher frequency charge pump in one of them, the TC7660HEPA runs at 120kHz.

This could of course go either way... It could help, or make the problem worse, but it's worth a shot.

Sounds plausible - thanks Robert. Wasn’t aware of “heterodyning”.

Just for grins, I asked ChatGPT what could be going on. Not a bad set of answers, but not as smart as you are ;-)

The whining noise in your guitar pedal when using an 18V charge pump could be due to a number of reasons. Here are some possible explanations:

1. Electromagnetic Interference (EMI): Charge pumps can generate EMI, which can cause whining noises in audio circuits. EMI is caused by high-frequency signals that interfere with the audio signal, leading to noise. To reduce EMI, you can try shielding your pedal, using high-quality cables, or placing your pedal away from other electrical devices.
2. Ground Loops: Ground loops can also cause whining noises in audio circuits. A ground loop occurs when there are multiple ground connections in a circuit, leading to a difference in potential between them. This difference in potential can result in current flowing through the audio signal, leading to noise. To reduce ground loops, you can use a ground lift switch or a ground loop isolator.
3. Poor Power Supply: A poor power supply can also lead to whining noises in your guitar pedal. The 18V charge pump may not be supplying clean and stable power to the pedal, leading to noise. To ensure clean and stable power, you can try using a high-quality power supply or battery.
4. Faulty Components: It's also possible that there could be faulty components in your guitar pedal. A faulty capacitor or transistor, for example, can cause whining noises in audio circuits. To troubleshoot this issue, you can try replacing components or taking your pedal to a professional technician.

Overall, there could be various reasons for the whining noise in your guitar pedal when using an 18V charge pump. It's recommended to troubleshoot the issue by trying out different solutions until you find the root cause.

 

[mkstewartesq]

Did you ever get this figured out? I’m having the same high pitched whine coming from my Cetus and it similarly appears to be pedal order dependent. In my case, I’ve got the Cetus and the Little Green Scream Machine in a two in one pedal with an order switcher.

 

[Dirty_Boogie]

Did you ever get this figured out? I’m having the same high pitched whine coming from my Cetus and it similarly appears to be pedal order dependent. In my case, I’ve got the Cetus and the Little Green Scream Machine in a two in one pedal with an order switcher.

I did order a bunch of the TC7660HEPA charge pumps that Robert suggested might help (or make worse!), but they really didn't make much of a difference. Tried various combinations of those with the 1044CPA charge pumps, but nothing made the Cetus's whine go away when the gain is up, and the Klon/Kliche is before it. I'm fine with the Klon after, so I just left it like that.

 

[Gt6371]

I need the collective brain power of this fine forum please to help me solve this... I have two PedalPCB pedals - a Kliche Mini (Klon), and a Cetus (Victory Kraken). I'd like to think I build quality pedals, with clean soldering, and clean, minimal wiring. Both pedals use a charge pump to bump up the voltage to 18V. I'm using high quality charge pumps, and a high quality isolated 1-Spot TruTone isolated power supply. My problem is this...

If the Kliche is placed before the Cetus, the Cetus emits a high-pitched whine when on. This is regardless if the Kliche is on or off (probably because it's "always" on as a buffered bypass pedal). Switch the order of the pedals, and no whine from the Cetus. I've switched out the charge pumps (other 1044CPA's). Also, same problem if using 9V batteries, and not the 1-Spot power supply. Removed all other pedals for this test video:

And the gut shots:
View attachment 44261

View attachment 44262

Open to any and all suggestions! Thanks.

I had the same issue. Move your phone or iPads away from your rig. Mine got a lot quieter when I moved them about 8 feet away.

 

[Haigster]

I’ve had the same issue with a number of Kliche builds. What makes me think that it’s not the Charge pump is, I built a bunch of Aion Klons which also have the 1044CPA chip and I don’t hear the high whistle on those. The problem is very obvious when I use the half speed button on my looper pedal and hear the high pitch whine at half the frequency.

Still an issue

 

[DeadAirMD]

I have the worst luck with the 1044's. I switched to the lt1054 and any and all whining ceased.

Every 1044 I have came from either Mouser or SBP. Could just be my setup or some other issue. My rig has 26 pedals, so trying to sift through cables, cords, power, etc is a real challenge. Ain't nobody got time for that!

 

[dlx]

I read somewhere that some charge pump chips can be jumpered to raise the clock speed out of audio interference range. Check your spec sheet.

 

[Haigster]

that's worth a try while I wait for me 1054 chips to arrive...
thanks

 

[music6000]

I did order a bunch of the TC7660HEPA charge pumps that Robert suggested might help (or make worse!), but they really didn't make much of a difference. Tried various combinations of those with the 1044CPA charge pumps, but nothing made the Cetus's whine go away when the gain is up, and the Klon/Kliche is before it. I'm fine with the Klon after, so I just left it like that.

I only use 7660SCPAZ & have never had an issue.
Every pedal I build & Test is straight after a KLONE with a 7660SCPAZ in it.
I have suggested this to Members on this Forum that get a whine from a TC1044SCPA & it has fixed the issue every time.
I have built about 30 pedals with 7660SCPAZ in them.

 

[brightlight]

I've built all the Victory V1 pedals except the Jack. I can confirm that this happens when using the Kliche Mini with the Kraken and the Sheriff, but doesn't happen with The Dutchess or the Copper.

 

[Robert]

I can confirm that this happens when using the Kliche Mini with the Kraken and the Sheriff, but doesn't happen with The Dutchess or the Copper.

What if you use the Kraken and Sheriff together, instead of the Kliche Mini?

 

[CR0SSBL4DE]

Are you using an isolated 9v power supply, so that all the outputs have separate isolated grounds?

 

[brightlight]

What if you use the Kraken and Sheriff together, instead of the Kliche Mini?

Good question, I'll try over the next few days and report back.

Are you using an isolated 9v power supply, so that all the outputs have separate isolated grounds?

Not sure if you meant me or the OP, but yes my 2 power supplies are isolated. A Voodoolab Pedal Power 2 Plus and a Friedman Power Grid

 

[DeadAirMD]

I read somewhere that some charge pump chips can be jumpered to raise the clock speed out of audio interference range. Check your spec sheet.

"The on-board oscillator operates at a nominal frequency of 10kHz. Frequency is increased to 45kHz when pin 1 is connected to V+. Operation below 10kHz (for lower supply current applications) is possible by connecting an external capacitor from OSC to ground (with pin 1 open)."

Quote taken right from 1044 datasheet.

 

[hamerfan]

Good question, I'll try over the next few days and report back.

Not sure if you meant me or the OP, but yes my 2 power supplies are isolated. A Voodoolab Pedal Power 2 Plus and a Friedman Power Grid

Maybe it's very outsided advise, but thats what I do to get 18v for a pedal. I bought an voltage doubling cable from Voodoo Lab, which is optional for the Voodoo Lab pedal power 2 plus. No troubles with oscillations.