As MM says, both will raise the grain, probably because alcohol contains some water, but that is not really a problem. Some dyes such as TransTint can be diluted with either water or alcohol. I prefer alcohol because it evaporates much faster than water and I can speed it up to dry even faster by igniting the alcohol. Most of the time, it isn't necessary because it is already dry before I can grab my Bic charcoal lighter.
Before dying, I do a preliminary step of raising the grain using alcohol in a spray bottle. I always burn off the alcohol when I do this step because it serves the purpose of removing the fuzz as well as enabling the wood to more readily accept the dye. I do not sand the wood between this step and applying the dye.
I apply the dye very sparingly with either a paper towel or an old t-shirt. It is always easier to add more than to remove excess dye. After the alcohol flashes off, I sand with 600 grit paper to lighten the harder grain and increase grain contrast.
I don't know if you plan to layer the stain to get multiple colors, but if so, the area where you will apply the second color should be sanded even further to avoid getting the colors dark and muddy. I aim for dyeing wood very lightly because my goal is to highlight the grain and not to paint the wood.
DO THE FOLLOWING AT YOUR OWN RISK -- IT IS EASY TO MESS UP A DYE JOB IF NOT CAREFUL:
Another trick that I do when dyeing maple is to very lightly mist the piece with alcohol after the final layer of dye has been added. This works best on highly figured maple and adds a slightly reticulated pattern to the dye treatment. This takes some practice. Less is better when misting. If you like what you see, stop right there because more misting will not give better results.
WARNING -- DO ALL BURNING OUTDOORS.
