I was wanting to get some advice. I just made what I think is a great estate sale score. I purchased a Mcintosh C24 pre and an Audio Research SP-5 pre for $20.00 each. This guy had a ton of electronics in his garage. Almost all junk, then I saw those two pieces and barely contained myself. Anyway, He said the Mac powers up, but one channel doesnt work and he never checked out the Audio Research pre. I'm not going to power up the mac untill checked out, I might power up sp5. The sp5 looks dirty but has a somewhat recent service sticker from a well respected shop in my area. My question is what do people think of these pre amps, which one should I keep, if any. I have a NAD C162 pre right now. I obviously want to keep one and sell the other two so I can buy more gear.