I use 1 4k 43-inch screen at about 80 cm. Works great. What helps is that lots of plug-in GUI’s are scalable nowadays.
Just don’t put the screen up too high, or your neck/head will start to hurt.
I have a Surface Book 2 15" (3240x2160) and a second 27" monitor (1920x1080).
Unfortunately, the difference in resolution confuses the top menu bar in Cubase (File/Edit/Project/Audio/etc.) which is sometimes displayed on the high resolution monitor without rescaling – so the menus and submenues are unreadably small.
The reverse doesn’t happen (no scaling problems with the 2nd monitor) but if I view menu items on the second monitor if I hover my mouse along the tool bar I see only blank menus unless I reclick. The normal behavior is to show the different menus as you hover without having to click, so not a big deal but minorly annoying.
(Fortunately, work spaces and dialogs are fine.)
This is an issue that is unique to Cubase, and not in any of my other software.
Otherwise my setup is great – the SB2 15" screen gives me plenty of real estate to work on the road or in performance. If I ever save up enough money, I’d love to have an ultra-wide 2nd monitor just to show a larger section of my timeline, but I can’t justify replacing my monitor when it’s working well except for this one issue.
Three, 24"
Two side by side for project and mixer and a third above them for mostly vsti’s such as superior drummer-mixer and pther plugins.
Hi 
For me two monitors, both Acer 21.5 inch HDMI widescreens. Had done this 2 monitor set up for years with my other DAW’s
I made sure the monitors are raised so that they tops of the screens,are at head/eye level.
My chair is adjusted for comfort and posture too.
I like the freedom of having say the mixer in one view while working on the arrangement in the other. Plus the feeling of much more room to work and breathe
I use 2 24". I generally have the Mixer console on the rightmost monitor and this is physically aligned with my 4 CMC FD controllers. The mixer is set to display 16 channels plus the CR.
i use 3 at home, and 1 monitor for live. One for workflow, one for the mixer, one for the EQ or a detailed view for an editor
I HAVE THE SAME ISSUE - ITS A BUG IN NUENDO/CUBASE
Menus from other monitor VST do not show up in right monitor.
It doesnt happen in any other DAws i use on same CPU (ableton, bitwig, FL studio)
Also HiDPI has so many bugs it is unusable.
Please Steinberg fix these issues for Windows users!
Pics:
-V
Two monitors - 1 for arrange/edit and 1 for mix/plugs.
I remember when Cubase was completely unusable on multiple monitors because of window sizing, it wouldn’t lock to a size or remember positions, very messy…
It works flawlessly (for me) with different monitors at the moment. (Most recent)
If anybody is thinking of taking the plunge, I can highly recommend
I use two - main is a 49" 3820x2160 (100% scaling) with a 27" 2560x1440 off to the left as a secondary.
The main display usually shows the project window, with mixconsole on the other.
2 monitors, 43" 3820x2160 main view + 24" 1920x1080 for mixer
I use one monitor, the samsung 32:9 120 hz. So it´s like two 21:9 2560p monitors side by side.
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