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

Your last post is classic cherry picking...

No you are cherry picking and must more likely have your back up over the "snake oil" voodoo'ist statement I made. As I'm a great believer in measurements, as that's how all gear is designed and made, and then listened to.
And those measurements can help buyers/users choose right amps for speakers and/or right speakers for amps, instead of the many "well serving" here but wrongly saying "buy this" it sound great, but don't have any idea if it will to the job measureless wise.

Cheers George 

@almarg superlative perspective, and as always, sage advice.
Thank you, Al

I do not believe "gain" to be the main issue here.  IME, the reason some hear improvements in dynamics and bass when moving from a passive to an active preamp is due to improved impedance matching through the volume control and consistent current delivery.  An active buffer (with or without added gain) can make the source's job of driving an amplifier easier by allowing the source to see a high input impedance into the volume control and the amp to be fed a consistently low output impedance following the volume control.  With the high'ish output of today's sources (i.e., CD players at 2V and  DACs at 2V to 6V) gain is probably not the main reason people hear improvements due to active circuitry.  

mitch2

I do not believe "gain" to be the main issue here. IME, the reason some hear improvements in dynamics and bass when moving from a passive to an active preamp is due to improved impedance matching through the volume control and consistent current delivery. An active buffer (with or without added gain) can make the source's job of driving an amplifier easier by allowing the source to see a high input impedance into the volume control and the amp to be fed a consistently low output impedance following the volume control.  

  Nelson Pass tends to disagree, with his Aleph L, he says when the active stage (which you would assume to be first class) is engaged on this preamp it takes a hit "his word suffer" in sound quality (3 o’clock or more) from when it’s in passive mode before 3 o’clock.

Nelson Pass:
At positions below 3 o’clock, the volume control functions as a precision passive attenuator using discrete resistor ladders.
Above 3 o’clock, active gain is added to the output signal in 2 decibel increments, for a maximum of 10 dB.
As a result, you suffer the effects of active circuitry only when additional gain is necessary.

Cheers George