I recently built a VTA ST-70. Stock kit, JJ E34L matched tubes and three 6189 NOS GE Preamp tubes.
The bias is fine, .4vdc and the sound is Incredible! BUT it has quite an odor. I thought it was the paper/plastic labels on the tubes (I've had them smell bad in the past with guitar amps).
I removed them and the glue residue too. Still puts out a strong odor. I would suspect the power transformer coatings or something, except all the voltages are fine, and the amp sounds very good.
I've run it for three to four hours a day for perhaps three days now.
It still puts off an odor that my wife can not tolerate! Any thoughts? (I do have a Mark V gas mask from my Navy days still!)