Power-modes | Prusa Knowledge Base

Prusa printers are well known for being very silent, even in the standard mode. But actually, our printers also offer an option for even quieter operation. In the instructions below you will learn how to set your printer to stealth mode.

MK4/S, MK3.9/S, MK3.5/S, XL, MINI/+

Starting from firmware versions 6.0.0 and above, two print modes are offered on the Original MK4/S, MK3.9/S, MK3.5/S, XL, and MINI/+. This is set by toggling the Stealth Mode. In idle mode, navigate to LCD menu -> Settings.

It is also possible to switch between Normal and Stealth mode during a print. In this case, navigate to LCD menu -> Tune. In this case, the selected mode will be activated once several G-code commands in the buffer (printer memory) are processed.

Once the stealth mode is enabled, the firmware sets a limit to acceleration, feedrate, and jerk values. Setting a cap on these parameters will lower the noise. The trade-off is an increased print time.

Screenshot from the Original Prusa MK4

MK3 and MK3S/+

Normal vs. Stealth mode

MK3 series printers offer two print modes. Normal mode is required for the detection of lost steps (shifted layers), while still being quieter than the silent mode on MK2/S. There is also the Stealth mode, which utilizes Trinamic StealthChop technology. This makes the printer almost inaudible where the print cooling fan is the noisiest part of the printer.

Stealth mode does not provide Crash detection (lost steps cannot be detected).

These modes can be switched depending on the situation:

When idle:
LCD Menu -> Settings -> [Normal / Stealth mode]
During a print:
LCD Menu -> Tune -> [Normal / Stealth mode]

MK2/S, MK2.5 and MK2.5S

Power vs. Silent mode

The silent mode uses less current and makes the printer quieter but less powerful. Hi-power mode is great for very large (over 200 gram) prints. It is also recommended for newly assembled kits before you fine-tune everything. If you experience lost steps (shifted layers) or if you’re manually adjusting the speed of printing to more than 100%, use Hi-power mode.

Auto power mode

There is also an Auto Power Mode. This is basically a compromise between silent and hi-power modes. The stepper currents depend on the Z height. The current starts low when the Z height is minimal. And it increases slowly as the object is printed.

These modes can be changed in two ways:

When idle:
LCD Menu -> Settings -> [Hi-power mode / Silent mode / Auto power mode]
During a print:
LCD Menu -> Tune -> [Hi-power mode / Silent mode / Auto power mode]

4 comments

bakegoodz

•

about 3 years ago

I think Stealth mode is a sick joke. I tried it and I hear a horrible high pitch vibration noise during x/y movements. I changed it back to normal and my printer sounds fine. Maybe it's a sign of defect? Only have a couple hundred hours of print time, so nothing should be wearing out yet. Keep it well lumbicated. Normal mode is pretty quiet, but stealth is loud.

Giuliano - Official Prusa CS

•

about 3 years ago

Stealth mode does make the printer more silent, so if it's not the case for you there might be something to adjust, maybe belt tension or bearings. In any case if the sound in normal mode doesn't bother you, there's no reason to switch to stealth mode and disable the crash detection.

Thijs

•

10 months ago

For my XL, the phase matching and stealth mode has made the printer significantly more silent. Great for overnight printing!

Michiel Haisma

•

almost 4 years ago

> Hi-power mode is great for very large (over 200 gram) prints.
I don't understand the reasoning behind this suggestion. Why is that?

David

•

almost 4 years ago

Hi! Because motors are stronger then and might not skip steps due to inertia on fast movements.

Michiel Haisma

•

almost 4 years ago

Does stealth mode affect the extruder motor or only the x/y/z motors?

PHerz

•

over 4 years ago

I never found the Hi-power mode on my MK3s

Official Prusa CS

•

over 4 years ago

Hi, that's because it doesn't exist for MK3s - it's only for older gen models based on MK2 electronics :)