It can be frustrating when you press Play and you have to wait what seems like forever before the sequence will actually play. This may occur when you're on an older system, have a long sequence at a high resolution, or have many complex effects (or any combination of those situations). Here's several ways to get the pep back in your system:

 
The quickest way to get better system response (especially once you have strung the whole show together or when you have an effects-intensive sequence) is to enable PLAYLENGTH. The PLAYLENGTH TOGGLE button (found in the Command Palette under the PLAY tab) can be mapped to your keyboard or interface. Here's how and why it works: Normally, when you press play, the ENTIRE sequence is loaded into RAM. When you have a long sequence, or one with lots of layers/effects, that's a lot of information to load in. That's why the system chugs along before beginning to play. But, when you use PLAYLENGTH TOGGLE, by default, it loads up 30 seconds of information before the blue position indicator and 30 seconds after*. This totals one minute (yes, I KNOW you know that! But, you will see in a moment why I point that out). With less information to load in, the system responds faster. The downside is that after 30 seconds (in this case) it will stop playing, and you must press pause or stop, and then press play to get it on it's way again. Also, be aware of Playlength being enabled during an OUTPUT as it will stop during playback. HOWEVER, if you have opened the DIGITAL CUT TOOL to make your output you have nothing to worry about, as this tool automatically ensures that the entire sequence is loaded into RAM before making the output.

 
You can also change the amount of time loaded into RAM by using the CONSOLE**. In the the console, type the following (then press RETURN -- Enter does not work) and you will get the results in the chart below (<space> means just press one space with the spacebar):

 
playlength<space>0 = this is like turning Playlength off. It loads the entire sequence into RAM.
playlength<space>1 = same as using the Playlength Toggle, it loads a total of 1 minute into RAM.
playlength<space>2 = loads 2 minutes into RAM (1 min. before the blue line and 1 min. after).
playlength<space>3 = loads 3 minutes into RAM.

 
These commands are good to know if you ever cut on v6.x or earlier, because there is no playlength toggle button. You HAVE to use the console. The cool thing is that if you type in your own duration into the Console, the playlength toggle button will then toggle between YOUR setting and loading up the entire sequence (though quitting Media Composer resets the defaults).

 
You can see the playlength being toggled on and off if you leave the Console open (though it does not have to be open to work) The next question is: If I don't have my Console open, then how do I know if Playlength is enabled of not? While it is sometime difficult to tell (in earlier versions of the software), it IS possible. If you pay CLOSE attention to the PLAY BUTTON under the RECORD monitor, you will see that when Playlength is enabled, the Play button is SLIGHTLY gray (as opposed to black). Press the Playlength Toggle button on and off a few times to see the change in the Play button. In version 10.x and higher, the Play button will turn white when Playlength Toggle is enabled.

 
Here are some other ways to keep your system frisky:
- Limit items in a bin to a total of 75 (master clips, subclips, effects clips, etc.) .
- Close unused bins.
- Limit the total running time of sequences in a bin to 2 hours. You may even want to create a "working" bin to store ONLY the segment of the show you are currently working on and close the main "cuts" bin.
- Delete unused precomputes.
- Take any unneeded partitions and/or drives offline. This is because the Media Composer software tracks or "looks at" all media on all drives, whether it is needed immediately or not, or even if it is part of the current project or not.

 
* In v8.x and later: Playlength Toggle loads 1 minute before and after the blue line by default.
* SAFETY NOTE: be careful what you type into the Console. It is a direct line to the Media Composer software code and Avid will not support problems caused by typing nonsense into the Console.