HI-FI NEWBIE NEEDS HELP!


I am new to the higher end of music listening, actually I haven’t started the listening part yet. I have just purchased an Emotiva XSP-1 pre and a pair of Magnepan 1.7i’s. My listening room is 14x14 but one wall is not closed off completely and there is an additional open space connected that is 8x9. My budget has been unexpectedly diminished more by having to buy new connectors and speakers cables. I just assumed I would be able to use my old RCA connectors and my 50’ spool of speaker wire I bought from Radio Shack 25 years ago. I will pause while you laugh....Anyway, the jist of it is is that I’ve got $2500 left for an amp. I need advice on what would be good for my setup? What would last the next 25 years, as I am a poor man with expensive tastes and will probably not be able to make any further upgrades. Would something used and older be out of date technically in 10-15 years? Could I consider something new that would be adequate for that price point? Should I go mono or two channel? Thank you for your consideration and reply.
widespreadpanic
" There are many silly stories going round here about the sonic character of amplifiers. If an amplifier is any good it will not gave a sonic character, even in the most revealing system. "

There are many silly posts from you such as this claiming everything sounds the same and yes among the contributors here there are a tiny noisy handful of those who make similar claims and who are quick to yell snake oil and yet among this same group of contributors there are many many more who do hear the difference. So either this tiny noisy minority are right and all the others have been deluded by this vast conspiracy of snake oilers, or the few who maintain that everything sounds the same are just misinformed or trolls. Perhaps you believe you have some nearly exclusive ability to define the truth but in much greater likelihood it is the rest of this vast diverse experienced and knowledgeable community that is right. 
I am not so sure this community is that knowledgeable about test protocol (and science is not a democracy I am afraid). Mind you, I recently did post some links to controlled tests that produced exactly the result that I claim. Do you have tests that demonstrate the contrary, or scientific data that prove/suggest that the kind of measured imperfections that we see in good electronics are above the threshold of human hearing acuity? There are enough audio professionals who will argue exactly as I do.
Willem, perhaps the scientific test tools are not sensitive enough. I can assure you my amps can sound different by even changing the substance they sit upon. 

So you claim that your hearing is better than e.g. an Audio Precision Audio Analyzer? Do you  have evidence for this?
There are many silly stories going round here about the sonic character of amplifiers. If an amplifier is any good it will not gave a sonic character, even in the most revealing system.

Every amplifier has a sonic character, just like every musician and band has a sonic character. That said, it doesn't mean two or more different amplifiers cannot have the same sonic character.