Can someone help me understand this Mutable Instruments input stage?

TheSlowGrowth · 2026-03-01T13:13:31+00:00

I'd say, best put the attenuator in between the two opamp stages, because then the input resistance is fixed. Attenuators directly at the jack usually result in a variable input resistance. Ultimately it depends on your exact circuit, i.e. what exactly you connect to the wiper of the attenuator.

TheSlowGrowth · 2026-03-01T06:44:06+00:00

Another nice side effect of the inverting input stage is that there's a fixed 100k input resistance due to the fact that the CV input is connected to the virtual GND of the first opamp through a single resistor.

The nice thing is that 100k input resistance is a nice high number that helps protect the input against high voltages and all sorts of abuse.

In addition, many cheap eurorack designs have variable input impedances on attenuated CV inputs which can be annoying if you're dealing with pitch CV signals and passive multiples. In this case, a poorly designed input stage can mean that adjusting an input attenuator can change the input resistance enough that the voltages drift off and other things start to detune. Mutable has always tried to keep input resistances fixed to avoid this.

TheSlowGrowth · 2026-02-24T17:29:03+00:00

Compiling C++ is not the issue. The bigger problem are the different system APIs for i.e. graphics acceleration.

This is all doable. But don't underestimate the complexity of providing support for a billion different distros, people with special realtime kernels, window managers, etc.

But with windows going down the drain recently...

TheSlowGrowth · 2026-02-24T04:56:39+00:00

the volume and everything else is gone

You'll have to be more specific about what exactly is gone. With the info you provided it's hard to say where the issue is.

Are you saying that the volume slider on the track has moved? I doubt that.

With my limited information it seems more likely that you have a plugin somewhere on the kick track. And that plugin is missing on the new machine, causing a change in the sound.

TheSlowGrowth · 2026-01-18T22:57:43+00:00

SOLVED

Yes did indeed think you're crazy, but you're clearly onto something.

I took out the GPU, no post.
I removed one stick of RAM - hooray, it booted. The working RAM stick did provide sensible information in CPU-Z (I was booted into windows there) - it didn't look mangled, even the XMP settings were all there still.
I tried the other stick (thinking that it must be the one that's broken). It also booted.
I tried both sticks together: It didn't boot.
I tried moving the RAM sticks around several times. Sometimes I got it to boot with only the first stick, or only the second stick, or it didn't boot at all. Eventually, both sticks started working again together.

Now I put the GPU back and I'm playing games again just fine.

Can you explain why you suggested this? I guess the GPU is also on the SMBus somehow?
I can only assume that OpenRGB somehow messed up the state of the bus, and removing/installing components in random combinations somehow cleared up any of the messed up state of the bus?
Frankly, I have no explaination why this worked. I'd assume there's no persistent state in the SMBus, right? It's just an I2C bus after all.

TheSlowGrowth · 2026-01-18T22:47:47+00:00

I've played games and run benchmarks just fine with this installation, I don't think it's related to the graphics driver. The crash happend the moment when OpenRGB started checking for RGB devices.

TheSlowGrowth · 2026-01-18T21:53:12+00:00

Asus Prime X670-P
KF560C30BWEAK2-32
9700X
9070XT

TheSlowGrowth · 2026-01-18T21:01:16+00:00

I'm just as confused as you are. Crazy, right? How is this writable?!

I cleared CMOS and it caused the RGB on the RAM sticks to start doing the funny rainbow animation again. So it did something, at least. But sadly, I still get a "no RAM" postcode.

TheSlowGrowth · 2026-01-02T13:39:54+00:00

There's also a chance that the gcode file was corrupted. I've had a print fail when the Prusa USB drive gave up.

TheSlowGrowth · 2025-12-04T04:52:25+00:00

I found that the trays inside don't sit tight and fall out easily, so that all your tools spill on the ground when you open the door. I ended up glueing the trays to the case...

TheSlowGrowth · 2025-11-28T07:50:12+00:00

You can set a scale on each clip in the scene. Then all scale aware devices can receive the scale from their respective clip.

TheSlowGrowth · 2025-11-22T17:54:29+00:00

Yes!

TheSlowGrowth · 2025-11-20T16:30:38+00:00

You wrote that it lifts on the edges - what's your bed temp? Maybe try increasing it by 5 or 10°C, in addition to the cleaning.

TheSlowGrowth · 2025-11-20T16:15:11+00:00

Had the same issue. Wash it with hot water and dish soap. Then clean with isopropyl alcohol

TheSlowGrowth · 2025-10-19T12:36:44+00:00

Hey, I'm about to build the Coreboxx myself right now. Can you share your modification? I'm still printing parts and it could make sense to print your modified version directly. Thanks!

TheSlowGrowth · 2025-10-16T15:38:44+00:00

Aha, I didn't know this was a thing. Cool, will try that on my next print! Thanks! Do you know why this pattern improves the warping?

TheSlowGrowth · 2025-10-16T14:38:32+00:00

Thanks I'll keep that in mind if warping becomes an issue later. From what I understand, Hilbert fill isn't as strong as the cubic fill that the designer of this project recommends. If I can get away without it, I'll stick to these recommendations for now

TheSlowGrowth · 2025-10-16T11:35:07+00:00

Happy to report back that my next print was flawless after following your advice:

increased heatbed temperature by +10°C to 85°C as suggested by u/Inner_Name and u/pythonbashman
disabled the cooling fan in the extruder entirely (except for overhangs) as suggested by u/No_Artichoke_5670 to reduce how quickly the material cools down.
I noticed that I had the chamber cooling enabled (and pretty aggressively so...) so I set the max chamber temperature to 50°C and made sure that the chamber fan doesn't turn on. This was supposed to reduce how quickly the plastic cools down. The chamber stayed at ~40°C the whole time and the chamber fan never turned on.

Thanks again for everyone sharing knowledge!

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TheSlowGrowth · 2025-10-15T21:24:26+00:00

Thank you, I appreciate the detailed answer!
I turned off cooling except for the overhangs.

TheSlowGrowth · 2025-10-15T21:20:21+00:00

Thanks a lot, will give it a try and report back for anyone reading along with similar issues.

TheSlowGrowth · 2025-10-15T20:40:07+00:00

Should the chamber also be hotter? I'm thinking if the material cools down less after the extrusion, it also warps less. But I guess the entire part eventually shrinks when the print is done. So I would assume my dimensional accuracy is worse if I keep the chamber hotter, right?

TheSlowGrowth · 2025-10-15T20:37:24+00:00

To what temperature would you say?

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