How much do I need to spend to get a preamp that sounds better than no preamp?

Find an Ayre K3x with phono. Why waste more money for little gain. Because it is new and fancy, doesn't necessarily mean you will get that exponential gain in listening pleasure.Use your spare cash on something else worthwhile to you. How many enthusiasts have "aging" componentry that cannot be replaced because yesterday's stuff was quality, todays is science and mass market, or hi-brow if you can afford it.

I didn't look through the chain to see if anyone mentioned LDR-based preamps but that is a good place to look especially with a high sensitivity amp like the McCormack.  My three buddies and I have replaced preamps from Eastern Electric, Counterpoint (highly modded), Parasound (JC series), and Slagle with LDR-passed no-gain preamps from Tortuga (various models) or Horneshoppe (the Truth).  In all of our experiences, these are the most transparent pre-amps we have owned with outstanding performance in the frequencies extremes, a gorgeous life-like mid-band, and deep and wide imaging.  For us, these preamps transformed our systems to higher levels then we thought possible and we feel we are no longer limited by our preamps, only by our sources, amps, and speakers.  They are really good at any price level and outstanding killers at their actual prices.  In addition, if you do need a little gain, Tortuga has a buffer that can be added and configured to add a little gain.  I believe both companies offer trial periods and both are owned by colorful, thoughtful people.

I have an easy way to evaluate a pre-amplifier.  A few years ago I obtained a Stax tube electrostatic headphone system.  By chanch I also had my then Audio Research LS26 tube pre-amplifier sitting right next to me.  Anyway I simply hooked my Stax system thru the LS26's record out outputs.  As at the time a long time user of Stax headphone systems, I immediatly noticed how the audio reproduction was greatly improved.  Not just a little bit but a definite audio improvements.  Now when I would take an audio source and hooked it up directly to my Stax system, the audio quality went way, way down.  Presently I am doing the same with an Audio Research LS27 and both a solid state as well as a tube Stax system.  As the LS27 has both a ballanced as well as a single ended output, with a pair of adapters I am able to hook up two different Stax systems.  Now in between I tried tje same thing with a Classe DR5 solid state pre-amplifier and got different results.  Now the Classe was a very good pre-amp, but the Stax systems would sound better if connected directly their audio source as compared to thru the Classe pre-amplifier.  Which brings me to the opinion that the question of whether to use a pre-amplifier or not might just rest upon the quality of the pre-amplifier itself.  The results are so much easier to compare if done thru a high quality headphone systems as opposed to a regular speaker based audio system.  Unlike a speaker bsed system, the results are easily noticible, and immediatly thru a quality headphone system.  Thru my LS27 I can match output levels and with a push of a button on my remote control go back and forth easily.  And again, the results are so easily apparent immediatly.  No need to go back and forth countless time to evaluate different audio components down the line.  Again, it is the quality of the pre-amplifier being used that will make the difference.

Well I got the pass preamp and to me it sounds a bit thin on the bottom compared to no preamp. The vocals aren't as warm and there is not as much Bass. Crap.

The LDR3 from Tortuga may be the way to go.