Welborne Labs Laurel 300B vacuum tube power amplifier....

Know it's almost 2 years since your original post, but have schematic if you still need.  Have had my Laurel 300B > 20 years now, still listen to daily.  Replaced output caps with Mundorf and some other caps with v-caps.  Mundorf was big upgrade. Have rolled several pairs 300b, currently using Takatsuki, but have tried Sophia Mesh Plates, Vaic Valve Blue Glass 300b and Sovteks.  Bought the Takatsuki at an amazing store in Tokyo that sells only tubes, have never seen anything like that.  Honestly, I'm totally happy with this - amp plan on keeping forever.  Have also rolled the input tubes, makes less difference than the 300b.  Using RCA now.  Finally, the rectifier tube matters - ran through a couple, finally got a Mullard.  Am surprised rectifier makes difference, but it does.  

Hi….just saw your Laurel note.  I have a very talented tech who went through the Laurel.  He made many upgrades and it is lovely.  Using a linear tube mz2 with linear power supply as the pre.  Tubes are Emission Labs 300bs, a Sophia 274b and northern electric 6ls7s.  The 274b provided a noticeable upgrade in warmth.  I initially used it with my vintage Klipsch fortes (alk crossovers), but they weren’t a great fit.  I now have open baffle Cantuck audio lil 15s…and am very pleased.  I recently picked up a pair of heresy 700s which I will eventually try with the system.  My email is barrybrup@icloud.com if you would like to discuss further.