Quote Originally Posted by junkeroos
I am planning of setting up a 2-channel music stereo system for my room (12'x10'). I decided for my mains would be the new Martin Logan Mosaic.
I'm with RGA on the quality vs. quantity issue as well given your chosen speakers. I offer one more avenue of choice if you do not have a vinyl setup: CD directly to power amp using passive attenuators. This answer isn't for everyone and careful component matching (including cables) is a must. Many CD players today put out more than enough current to drive most amps. Although I have heard a number of $10k + preamps on the market, none in my experience are perfect. Kick them out of the circuit altogether.

I stumbled on this realization when I replaced my CDP and moved the older one into the garage system. Originally I used an old Dyna PAS-3x but noticed that the gain control was rarely above 9 o'clock. So I built a passive attenuator using $15 worth of Radio Shack parts and tried that instead. It worked just as well. On a lark, I took my El Cheapo project downstairs and compared it with the $2500 ARC preamp - it was no contest. Bypassing the active stage of the preamp resulted in higher resolution, better dynamics and a more neutral tonal balance. I later built a higher quality passive for that system with marginally better results.

Here are the gotchas:

1. You need to make sure there's enough gain in the mix to avoid dynamic range restriction issues. On my big system, I have the fortuitous combination of high gain CDP (4 volt output) and sensitive amp (1.3 volt). I rarely crank the attenuators past the -10 db level. On my garage system, however, I cannot fully drive the power amp. I don't find that a problem since the Advents will get plenty loud enough with a 100 watt / channel Threshold Stasis.

2. The cable runs must be short and the cable of a low capacitance design to avoid high frequency rolloff. If you're interested, there is a calculator on the DACT site that will plot the response given the variables.

3. Multiple inputs requires playing musical connections. To some, that is either impractical or excessively awkward. I gladly switch the interconnects from either the passive or the preamp (for when I listen to vinyl) to the amps to benefit from the better sound.

So given a particular budget, you may get more bang for your buck with a CDP-passive-amp arrangement. If you've ever done some electronic wiring (I built a couple Dynakits in my teens) , you can try out a passive design for $15. I posted a recipe including part numbers on AA.

rw