I want to play Canon which requires more octaves than the 25 keys. I'm using an Alesis Q25 and Ableton 9 LE.
Certainly. You want to define a keyboard "split point", which is a certain MIDI note number. Above this number you want the keys to transmit on one of the 16 MIDI channels, and below this number you want the keys to use a different MIDI channel. Then you can have two instrument patches on those two different MIDI channels, set up to respond to notes in transposed octaves. You can achieve these settings on your MIDI controller keyboard and on your DAW, or in some combination of the two. Read your owners manuals and look for the term "define split point".
You can also do this by setting each instrument to the same MIDI channel and disabling the unwanted keyboard regions within each instrument.
This method allows you to define different settings for each MIDI channel. This also allows you to quickly switch between different instrument settings. This is useful especially if you are doing live performances. You can just progress to the next MIDI channel output of the keyboard to pass to the next instrument setting required in the song.