What improvements would I get with a "better" preamp?


Current preamp is Mapletree Audio 2A/SE Linestage, upgraded with Black Gate caps. Tube rectified separate power supply. 6SN7 per channel. Point-to-point wired. What could be better (for less than $5,000) and why? Must have RCA ins/outs, not XLR.

rockadanny

@westcoastaudiophile Not sure what you mean by "blind". If the tubes are the same nomenclature as what your preamp was designed for, what is "blind" about making some of your own comparisons?

@billpete “blind” means rolling tubes w/o understanding tube amp design fundamentals, "same nomenclature” tubes over decades have large distribution of key tube performance metrics, that’s why! designer uses tubes available in volumes, at the time of design, to guarantee performance, thus extra step such as verifying voltage map is necessarily. 

@billpete you can do whatever you want / pleased to.. being analog design expert, I am trying to warn, as tube rolling SQ effects could be interpreted wrongly. 

below is an example of load-line of tube in circuit. small changes in tube behavior btw. different manufacturers will cause significant performance impact of the amp. 

@westcoastaudiophile OK, thanks for that. I thought I was going to have to stop listening to music there for a minute. I'm nor sure of the overall harm in my mistinterpretation of the sound quality of a given tube in my collection. I call myself an "avid listener", which I have been for over 70 years. I never intended to build my own gear or even to know exactly how it works. I do enjoy listening. Just so you know, you're not much fun. :)) Have a good one.