What is the single best pre amp you have ever hear

I am not here to sell anything. I am a speaker manufacturer and had the opportunity to show at Capital Audio Fest with David Berning. David is an amazing man whom I respect greatly Even more amazing are his electronics. I heard his ZOTL ZH-30 amplifier and concluded it was the best sounding mid powered amp I have ever heard regardless of price. By best I mean able to play all types of music well. Back to preamps. Some preamps add this or that or sound euphoric or slow the tempo of music. This only shows up as you play other types of music At the show I was totally spoiled by the ZOTL Pre one preamp honesty. I thought it had the best timing and speed of transistor and musicality of tubes of anything I have heard to date. I would have to say it is on my top three list of best sounding preamps regardless of price. It is also the least expensive, nearly half the price of the others. Please before you respond try to have a listen to this extraordinary preamp. Let me know if you agree or disagree Thanks for you opinions Ralph