Should I stick to the same manufaturer?


What should be replaced first Preamp or cd player or something else?

System:

Speaker Cable- Monster M2.4s 15'pr.;
interconnects- 2m Monster M1000i;RCA connections not balanced- preamp will not accept balanced;
Speakers- Martin Logan Prodigy;
Preamp- Audio Research LS1;
Amp- Mark Levinson No. 336;
cd player- California Audio Lab icon mkii;
Tuner- Magnum Dynalab MD102;
electrostaticman
I would say that your cd player is not up to the quality of your other components and would change that first.
Lose the CD player AND the preamp AND the Monster Cable.
You've got some nice pieces currently being crippled.

Please don't get me wrong, the IkonMkII was a great player in it's day and not a bad player still for a second system.

The LS1, well I find that pre to contain a whole lot more than I like of the ARC house sound or what I call a "white" sound. Logan's can sound a bit thin at times, I'd put up a warm preamp such as a BAT VK50 or VK5i. I use BAT pre and Levinson amps on two systems, and I find great synergy. As to the CD, lots of good players out there. Use balanced cables, your 336 was designed with balanced topology and it will sound better balanced than single-ended. I'd get tubed CD player though, your mileage may vary. Good luck.

beemer
I'd want to audition some different ICs and spkr cables 1st. Good Luck. Craig
Great response: Recommendations on a used CD player? Should I stick to ML line for a Preamp and cd because of the communication links by ML. Thanks
I would suggest cables, then CD (I like Levinson digital in the right setup - and use a 390s myself, but would urge you to consider the audio aero with your amp), then pre...

I personally wouldn't do all levinson with the Martin Logan's. A little tube will go a long way in that combination I think. The CD player may be the right spot for it. No matter what, though, IMHO you should swap out the Monsters when you can...

-Jacob
Get a new CD player or an outboard dac (like the Bel Canot DAC 2 or MF dac) if your player has digital outs. Maybe change cable too. The other stuff is nice.
For cables:

New School:

Harmonic Tech
Acoustic Zen

Old school:

Transparent

For Cd player, please understand I am biased:

BAT VKD5SE

Good listening to you!
I would look at the simplest and least expensive items first such as the cd player and cables and ask yourself how much you want to spend and what is it about your system's sound that you would like to change ?
The Acoustic Zen Line of cables are fantastic as are the ones from Ecosse , Analysis Plus and others. A new cd player would depend on the amount that you want to spend but to get a nice upgrade you could look at the Rega Jupiter 2000 if you want a nice smooth, laid back and musical player or something like a Creek or Naim player that offers detail and speed. The new Bel Canto Dac 2.0 is another great piece and it offers upsampling . Other manufacturers also have nice cd players such as Arcam and Musical Fidelity to name a couple.
If you purchase a new cd player or preamp from a dealer have them send you some cables to try with your system as they are very easy to return .
When you have exhausted speaker placement, and room acoustic treatment exercises, and are satisfied with your speakers ---selected as appropriate for your room volume, and having gained sufficient self knowledge of the psycho-acoustic phenomenon in the process, spend on the gear to support the speakers, followed by the subtle difference in cables and tweaks.

Of course if you haven't found some very rare decent source material as a reference, it could all be an exercise in futility at that.

Try at least one of the CD's recommended at: http://www.linkwitzlab.com/Music for a reference if your goal is hearing the individual instruments as they actually sound live, and to reproduce the concert hall experience as closely as possible in your room, with your system.