It does not have to sound clinical or uninvolving to lack soul. I build a DHT preamp that has a selector switch so you can use five different resistors. Each one has a plus and a minus to the sound. I found the naked Vishay to be very open and detailed, the Audio Note very sweet, Carbon was musical but kind of boring sounding but good for poor recordings, Shinkoh was emotional sounding, involving so maybe it had more "soul" and the Caddock was what I preferred in my system, kind of had it all. With the Shinkoh you really felt like you were there when a singer really dug down deep. You could really hear the effect of the singers lungs expanding and air rushing out so it was emotional sounding to people who heard the preamp when I switched resistors. So IMO, more "soul". The other resistors sounded excellent but in direct comparison were lacking in "soul". Hope this was helpful.
Happy Listening.
Happy Listening.