tubesrule, Thanks for the info. I just purchased a quad of winged SEDs so I'm going to try these before I do anything else. I spoke with Bea at VTL and she was adamant about using EL34s and no variations, and EH EL34s were the only recommendation. Being a noob at tubes I have no idea if the fat bottles will work in my amp. I also leaned that the plate and grid voltages on the older ST-85 are 600v, so any tube has to be able to deal with that.