# Menu Bar ![](images/menubar.png) ## File ### New Clears the patch and loads the template patch (`/template.vcv`). ### Open/Save/Save as Opens/saves the patch from/to a `.vcv` file. Patches use the [JSON](https://json.org/) format and can also be viewed with a text editor. ### Save template Saves the patch as `/template.vcv` so it is loaded when creating new patches. ### Revert Restores the patch from the last saved state. ### Quit Autosaves the patch to `/autosave.vcv` and closes Rack. Rack also autosaves every 15 seconds to prevent losing work due to a crash, power failure, etc. ## Edit ### Undo/Redo Rewinds and plays back all actions that edit the patch. ### Clear cables Removes all cables from the patch. ## View ### Parameter tooltips Enables/disables tooltips when hovering over parameters (knobs, sliders, buttons, etc) which display the name, numeric value, and optionally description of the parameter. ### Lock modules Locks/unlocks modules from being moved by the mouse. Prevents accidentally dragging modules. ### Zoom Adjusts the zoom level for the rack from 25-400%. Double-click to reset to 100%. You can also use Ctrl-`-` and Ctrl-`=` (or Cmd on Mac) to zoom, or Ctrl-scroll. ### Cable opacity Sets the transparency level for patch cables. Double-click to reset to 50%. ### Cable tension Sets the relative length of patch cables. Double-click to reset to 0.5. ### Frame rate Sets Rack's screen refresh frequency. Rack re-draws its screen every [monitor v-sync](https://en.wikipedia.org/wiki/Refresh_rate), or once every $N$ v-syncs determined by this setting. Decreasing the frame rate results in almost exactly proportionally decreased GPU resources consumed by Rack, at the cost of more choppy motion. ### Fullscreen Expands Rack to fill the screen with no window borders. ## Engine ### CPU meter Enables/disables the measurement of time for each module to generate each sample (see [Sample rate](#sample-rate)). This displays a meter on each module with the number of microseconds (μs) and the percentage of time spent in the module's assigned thread (see [Threads](#threads)). The CPU meter consumes engine CPU time itself, so it is recommended to disable it when it is not needed for best performance. ### Sample rate Sets Rack's engine sample rate. Rack's engine works by repeatedly stepping the state of each module by `1 / sampleRate` seconds, producing 1 new sample for each output. A higher sample rate decreases the timestep, resulting in more accurate analog circuit modeling and digital algorithms, while a lower sample rate decreases engine CPU usage. Engine CPU usage is almost exactly proportional to its sample rate. ### Threads Sets the number of cores to be used in Rack's multithreaded engine. To minimize power usage and CPU resources for other programs to use, disable multithreading by selecting 1 thread. Using more threads increases CPU usage but increases the maximum number of modules you can use in the rack. It is recommended to begin with 1 thread, and if you experience audio hiccups, try increasing the thread count by 1. Continue adding threads until no hiccups occur. The maximum recommended number of threads is the number of physical cores in your machine. For example, a quad-core machine would likely maximize the number of modules by using 4 threads. Due to [simultaneous multithreading](https://en.wikipedia.org/wiki/Simultaneous_multithreading) such as [Intel Hyper-Threading](https://en.wikipedia.org/wiki/Hyper-threading), you may attempt to use up to twice as many threads as physical cores in your machine, but typically this results in worse performance with higher power usage. ## Library ### Login Logs into your VCV account registered at [vcvrack.com](https://vcvrack.com/). Email for account assistance. ### Update all Updates and downloads all new plugins and plugin versions added to your VCV account. Rack must be restarted to load new plugin updates. ## Help ### Manual Opens [this manual](QuickStart). ### Open user folder Opens the [Rack user folder](FAQ#where-is-the-rack-user-folder) in Windows Explorer, Apple Finder, etc.