Which OSs does REAPER support?
REAPER has been developed and extensively tested on Windows 2000 and XP. REAPER also runs on Windows 98SE and ME, Vista as well as Windows 7. Some people have reported successfully running Reaper on Linux using WINE. It has also been reported to run fine on Windows XP x64.
REAPER for Mac OS X works on 10.4 and up, both PPC and Intel Mac versions.
Which REAPER version should I choose on Windows ?
We got 4 different installers to choose from:
* Windows (4.3MB installer) * Windows x64 (4.9MB installer) * OS X Intel (7.2MB DMG) beta * OS X PPC (5.3MB DMG) beta
|OS||32/64bits||Notes and recommendation|
|98, ME||32||Windows installer(32-bit). Use 32bits versions of all your VST plugs.|
|XP, Vista, Win7||32||Windows installer(32-bit). Use 32-bit versions of all your VST plugs.|
|XP, Vista, Win7||64||Windows x64 if...|
|XP, Vista, Win7||64||Windows installer(32-bit). REAPER will use about 3 gigs and you can use REAPER's plugin firewalling so your plugs will have their own 3 gigs instead of sharing REAPER's memory.|
Discussion (October 2009): http://forum.cockos.com/showthread.php?t=44660
Which soundcards does REAPER support?
Pretty much every sound card should work well in Reaper. Reaper has been tested with a wide variety of sound cards, from very low end ones (laptop integrated sound cards) to high end ones (RME, Motu, etc...).
If you are undecided about what hardware to get, the REAPER developers are using Motu 896s and are EXTREMELY happy with them :)
There is an ongoing discussion about working soundcards here: 
My soundcard Just Doesn't Work - What do I do?
Well - start from the beginning.
- Go through the instructions for your soundcard again (I know, you did already) paying particular attention to the "before you start" section. Does it say you need a particular service pack or version of Windows?
- Use the ASIO driver that came with your card, if there was one. Use ASIO4ALL if there wasn't one.
- Fix one thing at a time. Don't think of firing up REAPER until you have your sound card playing system sounds and playing CDs.
- Try a clean install of Windows, don't install all of the supplementary cool looking drivers and things that came from the manufacturer of your PC. Install as little as possible, then get the soundcard working for system sounds and CDs, then the get soundcard working with REAPER.
- Once you have it working you can start to install other s/w you need. Test at each stage. Be prepared to go through the whole thing again if something stops your soundcard working
How do I use my VST effects? How do I record my VSTi instruments?
Why Can't Reaper find my VST effects?
First of all, maybe it doesn't look for your VSTs in the right directory. Go to Options > Preferences > VST Plug-ins (http://www.cockos.com/wiki/index.php/Preferences_Plugins_VST), and point REAPER to your VST effects folder. Then, click on Clear cache and rescan directories. This last thing, to clear the cache and re-scan, you can try whenever plugins you expect to see, do not show up.
Note that prior to Reaper v.3.2 (was it?) 32-bit plug-ins do not work straight away in 64-bit Reaper and they will not even show up during scanning. You need the JBridge (or something similar) to use 32 bit VST plug-ins in a x64 host. From Reaper 3.2 onwards, the 32-bit bridge is built in, and you do not need any extra SW to use 32-bit plugins in 64-bit Reaper.
Some VSTs are tied to specific hosts, and refuse to show themselves to Reaper. This Reaper cannot do much about. Also, some plugins report an entirely different name to Reaper, than what their file name or product name is. So look carefully if a plugin expected to show up, doesn't show; it may be there under a different name.
What does the "Preferences/Plugins/Reduce Normalization from Plugins (recommended)" box do?
This option adds a small (VERY small, i.e. -300dB) DC offset and/or nyquist noise to signals. It uses a tiny bit more CPU to do this, and is slightly less precise, but can have big performance advantages. It is recommended that most users leave this option enabled.
How can I lower the volume of many tracks or items at once?
Select multiple items or tracks by holding down Control. Go Here for more info.
You can also put the tracks into their own folder track, and adjust the volume on the folder track.
My playback is stuttering, how do I fix that?
There are a few things that can help to give smoother playback in REAPER:
- Before you do anything too technical - What did you do just before it started to pop, click and generally drive you insane? More than once I've been recording some audio, fiddling with effects. recording audio, more fiddling (during which I've added something like ReaVerb) and then more recording and it's started to misbehave. ReaDelay - like a few VSTs that use an impulse file to generate reverb - does not play well with real-time audio... In this situation if you disable the FX chain the troubles go away. It won't always be ReaVerb, but it will always be the thing that changed last. This "thing" might be an added track, some software now running in the background, a disk that's now seriously fragmented. The rule is If you've had it working then something happened to break it, go find the something.
- Increase your audio device buffer sizes.
- Switch to ASIO output (Options > Preferences > Audio > Device). If your soundcard doesn't show ASIO, try installing and using ASIO4ALL.
- Change the track buffering options (Options > Preferences > Audio). Try incrementing the number of threads, buffers and buffering.
- Make sure the selected devices in the audio configuration are the proper ones.
- Check to see if there's an effect that's hogging CPU power. The amount of CPU used by the effects is displayed in the Effects dialog box per track. You can also temporarily bypass all effects (see these directions for mapping a keyboard shortcut) in your project to reduce CPU usage.
- Check for the memory usage displayed in the Performance Meter window (Ctrl+Alt+P to show/hide). Make sure that there's some System memory left for REAPER.
- Defragment your hard drives.
- Are you trying to work with too many tracks at once? See if you can combine some tracks into one - render all of the vocals into one track for instance. If you're keeping kick, snare, hi-hat etc. all on separate tracks think about mixing (rendering) them down to one stereo track instead of the eight that are currently making your PC gasp for breath.
How do I create a CD of my final mix with REAPER?
Select Audio CD Image (CUE/BIN format) in the Render dialog. Check the Burn CD image after render option.