Heya SteveD -
Are these forums always so hostile? 4 posts in and I'm already being attacked by trolls. Sheesh.
Thanks for the insight as to what gear you're using. Yeah, 8 tracks is definitely not enough for drums under most circumstances... though sometimes I will mic a drum kit with only 4 mics, generally I use 12-14 (always 2 on the kick, sometimes 2 on the snare, hihat, 4 toms, room/overheads, a 3d mic literally over-the-head, and sometimes a separate mic for the ride).
One thing you could do (if you felt so inclined) is to chain together two 1604s. That was what I was thinking about doing at first, but I wanted something big and snazzy to impress clients with (and it works too). Although one thing you might consider doing is to use your submix busses as the outputs to your DAW, unless you've got them already used for something else. That will at least give you four more channels with eqs and faders... that is unless you believe that there is an unacceptable amount of added noise if you do it that way (while technically there is, it's so minimal that even someone as anal about noise as I am doesn't worry about it).
About the whole preamp / no-preamp thing, this gets into a kind of subjective conversation that I can't really give you any definitive answers about. My take on it (though I don't have any gold records to my name yet, so my opinion is only worth what you've paid for it) since I've watched over the entire process from tracking to release more than a few times is on one hand, it's better to have the best possible signal being printed... but on the other hand once your mix goes to the mastering lab, the mastering lab tends to even everything out, making the difference between a vocal (or anything else) tracked with a nice pre-amp and that wasn't a perhaps immaterial difference in sonic quality.
In fact, I have on tape somewhere (I really should post this to my forums too so you can see what I mean) somewhere where I had a session that I was doing some work on a vocal that had been tracked at 'The Mothership' : Steve Vai's studio in L.A. on their snazzy API board, Avalon pre-amps, and AKG-C12 tube mic. Basically I had to punch in one word in a phrase. I figured I would try and EQ it to match it as best I could and try to bury and differences left-over in the mix... and since it was only one word it would probably go by pretty quickly. I used my one of my tube mics (brand omitted to appease the troll) going straight into my Mackie 24x8, and the vocal matched, well, pretty damn close (with no EQ btw). So close in fact, that I solo'd the track, put it on CD (just the vocal track with the phrase that had the punch-in), took it to M.I. to let some engineering students listen to it and see if they could figure out where the punch-in was, and NOBODY COULD TELL! It took the teacher 3 passes before she could figure it out, but none of the students in three different classes were able to tell.
Now, I will admit that there was a very very subtle difference that I could tell (well, of course I could, I did the punch) but after the rest of the tracks had been added, FX added, and then the mix taken to the mastering lab, well you get the picture.
Now I'm not saying that I don't hear a difference between normal mackie preamps and nice snazzy preamps like the Avalon, but one of the points I'm trying to make about the whole subjectivity issue is that after listening to so many mixes, mixes after mastering, and regular commercial CDs, the end results are all so wildly different from one another (well, to me at any rate) that any choice of gear is going to be a matter of personal taste.
This is one reason I'm hesitant to reccomend any high end pre-amps (or even
a presonus M-80) for someone building a home studio. One thing to keep in mind also is that if you only have enough $$ to buy pre-amps to make your cymbals shimmer, but not enough for the whole kit - that shimmering might imbalance the rest of your track when you take your mix to get mastered. If you're going to get good pre-amps, make sure you get enough to cover as many inputs as you use simultaniously.
My advice though, is to make sure you listen to anything that you are thinking about buying and make sure to consider the 'big picture' when you're listening. If all a $3000 preamp is going to give your final master is a mild difference in color, is it really worth it? Also, if personally you can't tell any major difference between preamps, keep in mind that there are many steps before something gets released and the extent that you're going to be able to be picky in your mixing is the same extent that you're going to be able to picky in distinguishing tones between preamps.
On the other hand, if you've got the cash to get the nice preamps, good mic cables and wiring (suggested brand omitted to appease the troll, but you'll find it in all the major studios), then it might make your mixing less of a headache and your mix might be somewhat easier to master - even if the potential of the quality of the final results with or without the nice gear is basically (tone/coloration differences aside) the same. It's also a good idea if you want to have those names in your studio so you can charge more per hour.
Sorry if I'm rambling extensively and causing any confusion. I guess in summary, don't take my word or anyone else's word for what 'sounds good'. I've heard great mixes that were made on a cassette 4-track and then run through a finalizer (not that the finalizer is at all my preferred choice for mastering btw), as well as crappy mixes that were made on a Neve console with all the trimmings... but you need to work with whatever you feel comfortable working with.
btw; Nice computer.
I have one that is a little more than half that fast that has handled 80 track projects with gobs of effects. You should be _quite_ comfortable on that machine even if everything goes dvd-audio.
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