What are the *real* power requirements of the Quad Cortex?

The manual says 12-V and 3 Amps (which equals 36 Watts). The maximum capacity of a CIOKS DC7 isolated switch-mode power supply is 42 Watts. However, it could power the QC with 4 outlets which sum and increase the amperage to 3 Amps.
Then came along the CIOKS CRUX, which I’ve purchased, which uses the 24-V connector and has a 12V setting. However, this gives only 2 Amps of power. Yet it’s known that the QC functions properly with the CIOKS at 2 Amps.

So are the power requirements of the QC 2 Amps or 3 Amps? Or is the CIOKS CRUX leading to a suboptimal experience by only giving it 2 Amps when it requires three?

I ask because digital processors are not at all like analog gear or pedals. They can’t just accept lower currents or voltages and continue to work. They just shut off or glitch out. If it dips in power, it will just reboot or shutdown. If it still functions without proper power, it can run sub-optimally at a reduced volume or have other problems.

So has Neural DSP ever commented on this?

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I bought the CIOKS DC7 and Crux a month ago to power my pedalboard with the QC at the center. I too wish they would simply say one way or another what the exact power requirements are. I am very happy with my setup and I am sure the CIOKS would not be endorsing a sub standard voltage for the QC. So am I saying I would trust CIOKS more than Neural on this point? Yeah, after much looking around I chose CIOKS as my standard. It just makes me feel good about my rather large investment.

This was a big topic of discussion in the Quad Cortex official Facebook group. I’m an electrical engineer, so when I see a power rating of 36W (12V @ 3A), I make sure that whatever power solution I use is fully capable of supplying that. However, a lot of users have gotten away with using 24W (12V @ 2A) with no issues. Neural have kinda sorta confirmed here and there that 2A is okay.

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I just don’t understand the ambiguity? With such a high end unit, why leave it so subjective? This is a rhetorical question at this point… but for the people like you that actually know what is involved electrically speaking it must be pretty uninspiring. Like I said in my post I went with CIOKS, not because I even understand the technicalities of electricity, but because their reputation is one that many are confident in.

I wonder what the story is on the official power supply replacement that was supposed to be developed. Pretty quiet on that subject lately

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Yeah, I am not one to wait around so that is why I spent over 300.00 for what I believe was the best way to power the unit cleanly. In fairness, I have never had any of the noise issues or intermittent glitches that others have had. I just wanted to have the best power supply I could get.

The ambiguity used to make me mad, but I simply chose not to get bent out of shape about it anymore.

In engineering there is a difference between “nominal use” and “corner case” conditions. I imagine 2A is a nominal use case that covers >90% of what users need, and perhaps 3A is a corner case condition where some users need to drive more outputs at max volume, play more resource-hungry presets, etc. I have no way of testing this at the moment, but it’s a working theory that I’ve settled on.

(This isn’t the place to describe corner case conditions in the aerospace power electronics industry, but boy oh boy do I have stories. Let’s just say I am intimately familiar with how much current you can push through 0.001" thick gold wire at 125 degrees C.)

For those reading this for the first time, there are definitely much cheaper ways to get clean power.

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I appreciate this reply. I always appreciate your replies! :slight_smile: So I was already well covered but now I am especially well covered since I will never even approach 70 percent of usage! I do like the idea of having a really good power source for not only my QC, but my other rather high end pedals as well. So I am a happy camper. Thanks again for adding some insight to this technical issue. Of course Neural knows and understands these things. So no slight on them, but if they cared to share this kind of information it would indeed help people like me to know how I stand when trying to optimize my board.

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Working in cleaning up my studio wiring including the QC. I have MXR Iso Brick , MXR® ISO-BRICK™ POWER SUPPLY - Dunlop, which I used on my gigging pedal board and am going to use it in studio now. It has two adjustable 6-15v 250ma outs. Of course I’ll use my multi-meter to make sure I’m on a solid 12v and it seems the consensus is 250ma should be enough juice for my not very effects intensive presets.

No, it is not. You need at the very least 1500mA to power the QC. But even that is kind of risky. I would not go for anything less then 2000mA.

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Never mind got my zeros confused looking at a fuzzy picture of the OEM…more coffee!

Voodoo Lab has stated that you can use the XLink (2A) on their power supply to power the QC. They mentioned this in a comment on Instagram:

“X-LINK ports will deliver up to 2A in total between the two shared expansion ports. The actual current draw of the Quad Cortex is 1.8A. This was measured on our end and also confirmed by Neural. 3A is the rating of the wall wart that ships with the Quad, and that is the rating chosen as the published requirement. 3A is not the actual current draw of the Quad. The wall wart current rating is commonly used as the published rating for effects devices by manufacturers. There is no way to damage the Quad Cortex by powering it with X-LINK. The only thing to keep in mind when powering the Quad Cortex with X-LINK is that you should leave the second expansion port empty.”

Neural Dsp support, in an email I sent them, confirmed this information.

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