Preamp or Amp?


I started a thread that has gotten no responses so I've started another one. Hopefully this is much more direct. I have a simaudio intergrated amp. Would I hear a difference moving up from an i-3 to a higher i-5 or Classe' 151 OR would I be best to move my budget up slightly and begin the trek down the seperates road.

Does the Preamp effect the overall presentation of a system more then the amp? I will be using Polk Audio LSi15 speakers. At what level of separates will I hear a significant improvement in sound quality? I've been doing some light reading, and have read up on some preamps the Copland 305, some CJ units...regardless of what I buy down the road, it will be used. Can a Jeff Rowland concentra or SimAudio i5 really keep up with most separates? I've been told by a few people they can. I'm not sure if it matters but the source is a John Wright modiffed Museatex DAC/transport combo.

I like the idea of simple one box solutions, not to mention the money saved on wiring. But a few people on this forum have told me if I like the sonic signiture of the LSi speakers, perhaps maybe it's time to look at getting a dedicated amp/pre-amp for further improvements, if thats the case which should I get first, the amp or preamp?
lush
I'm going to make a suggestion that might be so obvious that I'll get hooted off the board. If your current integrated has a capability to separate the pre and power sections, perhaps you could work with a dealer and get some pre's and amps that fit your budget to demo. Try a pre using the inputs to the power amp section and then compare the sound to using the pre-outs from your integrated with a better power amp. The comparative results might tell you where your money could best be spent. Then you can stagger upgrade purchases appropriately to get biggest sonic bang for your budget.
Brainwater: I've heard many great things about the Totem lineup. I've heard the Mani2's powered by Simaudio Celeste and wasn't impressed at all, even the owner of the Totems prefered the LSi's to his older Mani2's. Perhaps it was the mix, but I found the presentation to be stale, the LSi's really bring you in. I can listen for hours.

I've always been a source first guy, hence the reason I've spent so much (or little depending on how you look at it) on my redbook player, to ensure everything upstream would benefit. I really don't know what kinda level of preamp amp I would have to get in order to best a top flight intergrated like the Simaudio i-5 or Classe' cap 151 any suggestions?
I am going to step quietly back into this . I have just purchased the CJ Premier 350 solid state amp. I have never been as shocked by a solid state amp as i am by this thing. I have always had a more signifigant impact by preamp upgrades ... till now . I now am rethinking my theories .... again.
Lush;

It makes sense that a Preamp will make more of an impact. They "manage" signals that are very small in magnitude and amplify them to drive amps. If something goes wrong at that low level of magnitude, once you amplify it, you'll also amplify the "mistakes" made. Most audio-designers would say that is a lot harder to build a proper preamp, than it is to build a proper amp.

As far as the I-5 Vs the I-3 goes...both are good amps, the I-5 is more refined though. On the other hand, as an owner of a LSi15 pair, I can tell you, they like power. They like an amp that can take control of them. So in that sense the I-3(since is a bit more powerful than the I-5) could be a better match. I would suggest trying something even more powerful. If you like the convenience of integrateds(as I do) and need something powerful, I'd suggest check out the Perreaux integrateds. I've had the Perreaux 200iP, and now I have the Perreaux Radiance R200i(both are rated at 200Wpc at 8 Ohms and about 350Wpc at 4 Ohms), and I'm very happy with the results.
Forgot to say...

Are the LSi15 one of the bigger bargains in all of Audio or what??

Its funny cause a lot of people would just dismiss them because of their brand name. I auditioned a pair of Sonus Faber Grand Piano speakers. Couldn't justify selling my Polks to by those. In fact, I downright preffered the Polks.