Once again, thanks for the replies, this has been really interesting. I posted the same question and samples on two other forums, Larrivee's, and the AGF and got 23 responses.
J7, the first sample, was most frequently described as "brighter", with a few "more sparkle" and "has presence" thrown in. Some weighed in with "tinny" and "brassy". If you guessed this sample had the brass pins you were in good company.
Q1, the second got described as "muddy" a few times, as well as "muted" and with "less resonance", though others described it as "mellower". Only 3 specifically stated this was the one with the brass pins.
The reply I found most interesting was from "wrench68" on the AGF forum who weighted in with: "It looks like your top frequency dropped from 196 Hz to 183 Hz, and the volume dropped a few db, among other things, in the second sample. These are all characteristics of adding mass to the top. I'd say the brass pins are in the second sample, and in my opinion, they did not improve the sound of your guitar."
My initial impression when I played the guitar after placing the brass pins was that it sounded brighter, but I think this clearly shows that is what I wanted to hear, having gone thru the trouble of changing out the pegs. I've since played the two tracks quite a few times, alternating a section at a time, and with the feedback I've gotten I agree with how you guys are describing how they sound, so perhaps my hearing doesn't suck as much as I feared.
I think there is a lot of merit to the idea that the extra weight of the brass pins over the wood ones really does dampen the soundboard, making the tone muddy, less resonant and muted. I weighed the ebony pins at .2 oz, a set of bone pins at .25 oz and the brass pins at 5 times (!) the weight of the ebony at 1 oz. That some of you mentioned trying brass and liking it, I think suggests another consideration might be the size of the guitar and style of bracing. My cutaway grand concert is set up for light gauge strings and has a much smaller soundboard surface area than a dreadnaught, so extra weight would dampen the dread less. The brass pins could work for a larger guitar set up for mediums and as someone suggested one could try a partial set, say 2 on the unwound strings.
I think it's safe to say that the popular notion that brass pins can brighten up your tone has been disproved somewhat, at least for smaller finger-style guitars. They perhaps do some, but they take away perhaps more than that's worth.
The biggest take-away from this experiment for me was that the Taylor 12 sounds pretty good as is, I should leave well enough alone. Also I appreciate the kind remarks on my playing.
Thanks again everyone, I appreciate the help and hope you found the results as interesting as I did.