Based on room size, how to select the speaker size and power

Hi there Based on a room size, how can we select the size of speaker and the power of speaker? Right now, I am designing my own small studio room. Only for vocal recording. The control room is 3(L)*4(W)*3*(H)m. Very similar as Patrick's Den Recording Studio http://www.johnlsayers.com/Studio/Pages/Giles.htm The current speaker is 4'', M-Audio AV40. Please see the following link. http://www.m-audio.com/products/en_us/S ... eAV40.html I am prefer to have Mackie HRMK2 624 or 824. http://www.mackie.com/products/hrmk2series/index.html Could you help to tell the relationship between room size and speaker size? The room will be acoustically treated. All the inside surface will be added sound-absorbing materials. The minimum place will be 50mm glassfiber + 50mm space.

I'm not sure it matters. most near fields have similar sensitivity and amps. Most of them are copies of other speakers anyway, so they all have similar dimensions as well. How much do you have to spend? What do you like the sound of?

Hi lilith_envy Thank you for your fast reply. I prefer the bigger speakers, because the bigger one can give us more power, somehow higher quality, and looks professional. ^_^ For the budget, maximum $700 will be on one pair of monitors. For other money will be for decoration. For the purpose, it is pop music. Also, the first design was attached. There is very limited place for activities, so the design was cancelled.