Where to put the better cable.

Here's the scenario: CD > Preamp > Amp - that's two pairs of interconnects required. One pair is much better quality than the other, so where should the better quality cables go? CD > Preamp or Preamp > Amp ? I'm talking in general here. Of course the best thing to do would be to try it both ways and listen, but there must be a rule of thumb about this.

preamp to amp.
At the beginning of the series. CD to preamp (if you only listen to CD (no LP)
The reason is 'garbagein garbage out' IF you put the good wire pre to amp and the modest wire CD to pre, then the modest wire starts out lessening the signal straight away, NEGATING any goodness of the better cable later on in the chain...compared to the other way around.
Putting th good cable first at CD to pre, the quality of the sound is best it can be through the pre, and then it may be lessened a bit by the modest cable.
The real thing IS to try them and see... but the logical way is: better at source.
Try them both ways and stay with which one sounds better to you. All gear reacts differently to different cables. Also keep in mind that the signal has to pass through both cables either way.

If you are using more than a CD, then putting it between the preamp and power amp will improve all the gear plugged into the preamp; not just the CD.

My most "expensive ($$$)" cable is between the CD and preamp, HOWEVER , the cable between the preamp and power amp is the best cable for that position, even though it cost less than half what the other cost. It has better "PRAT" in the pre/power position than any other cable I've tried regardless of price or assumed quality. It simply works period...

The same goes for my FM tuner. It has the best cable for it I've tried, not the most expensive.

The "better" cable should be the one that sounds better. Forget about price or quality of materials, etc..
I agree try both ways
Obviously, (though I would go cdp to pre/ always the source) no clear cut answer here. Let the ole tympanics decide for you. They'll never steer you wrong...peace, warren
Try both ways, but if the lower "quality" (whatever that means) cable is really junk than you're better off NOT using it at all, and at least substituting a known inexpensive reference IC for comparisons. An easy wnner here is the $20 Canare StarQuad mic cable the pro recording engineers use. Try TWO of them, substituting your "better" cable in each place sequentially. Try to have a buddy help you for a single-blind setup, so you don't confuse cost with "quality", as you put it. Cheers.
It doesn't matter a whole lot. Remember, your system is only as good as its weakest link.
Timo is correct. It doesn't really matter where you put it and it will always be your weakest link.
IMHO, always use the cleanest, best imaging, sound stage, and full freq response on your source ( Pretty much the best cable you can get ) and swap around the preamp to amp cable for your listening preference.
Remember, if it sounds bad from the source then it will just get amplify to a greater degree from preamp to amp.
Everyone makes good points. Yes, ultimately it comes down to what sounds better to my ear. Just wanted some opinions. Thanks everyone!

For those curious about the details:
Simaudio Moon Nova
Harmonic Technology Magic Link RCA
Simaudio Moon P5
Harmonic Technology ProSilway II RCA
Simaudio Moon w6

And, yes, I know, I would be better served using XLR. Will do that when the budget allows.

You will end up with them where they sound the best, but if the question were asked, and the results could never be altered I would agree with Elizabeth.

Always get the most signal off of your source. No great piece of gear will add what wasn't obtained from the CD in the first place.

My mode of upgrading is always to start at the source and move back to the speakers.
Interesting thread and comments. Elizabeth's comment would be my first choice but time after time, I have found the most crucial cable link in the system is between line stage and amp. I have run a mixture of Cardas Golden Cross, SilverAudio, MIT 350 and NBS Statement. At one time I even used a cheapo pair of Belden. With the NBS being 100x the cost of the Belden, the Belden was still quite good between the phono and line stages at the time (ARC PH2->ARC LS5III) but the Belden was absolutely terrible between the LS5 and amp (VT130). All of the harmonic richness and 3D of the system was gone with a mediocre cable here and yet from the phono stage, it was mighty good! It is not always about resolution or "best cable to the top of the chain". I think it has as much to do with the cable interface between the output and input links.

Over time I switched to NBS in all links, each time making an improvement in system performance, but still trying the Belden from the phono stage to line stage, now Aesthetix Io -> BAT 31SE, shows quite a decent link....but even more so a musical disaster from line to amp. The second most critical link from my experience is the tonearm cable and then 3rd, from DAC to line stage. I too tend to start with what common sense would indicate, but my ears often tell me something very different. So the only way is to try for yourself.
That's not a correct way to compare since the belden was not able to match your preamp and amp ( LS5 is balanced and the belden was never intend to be used for balanced application.)
Different component pairs will react and sound different based on the IC between them. Try it both ways and see which sounds best to your ears. Just remember that the 2nd one in the chain can't add anything to the signal, so the most transparent and uncolored IC should probably work best higher in the chain, but like everything else, that may not always hold true.

Just to complicate things a little bit, changing the direction that the cable plugs in may also alter the sound, as will the polarity of the AC plugs on each component. Makes for a nice challenge to identify the "best" setup. Now multiply that by several components and you have a year's worth of trial and error to go through.

Happy holidays,
Cables react differently to each component due to output and load impedances. Just try at each component to get the best results.
S23Chang: The particular belden cable I have indeed has separate signals for each phase. Whether or not it was "designed" to run this way I don't know...but it has 3 distinct lines and thus allowed the LS5 to run in its truly balanced topology. And it worked mighty well from the truly balanced PH2phono stage to the LS5 line stage.

The belden cable aside, I have owned cables as indicated previously as well as tried others such as the AQ Diamond which literally robbed the system's 3D presentation and ambience when used between the LS5 and VT130 ... but it worked quite well between PH2 and LS5.

The Cardas Golden Cross was an excellent value cable between the LS5-VT130. Its warm emphasis in the mids captured the LS5's magic. The SilverAudio Appassionata in this link brought on somewhat of an analytical sound but captured more low-level resolution than the CGC from PH2-LS5. Which one is better? "Better" is not the issue here. Each cable clearly had a synergy within certain links in the system. But the LS5-VT130 link was always the "make or break" in the chain when it came to getting that magical sense. And today I fine the same is true from my BAT31SE to Counterpoint NPS400.

So it is not an issue of the Belden but rather due to interractions which I am not qualified to desribe...all I can tell you is what I observed sonically.
Timo, S23. Since impedence-matching requirements are probably quite different between the two sets of component interfaces, and the LCR values of the two cables are probably different, it DOES matter where each goes. It is rarely a case the weak link being a constant independent of position....