The dual rectifiers have a lot to do with the transient response of the 5E8A---it doesn't sag up like the other 35 watters (Pro, Super, Bandmaster). You can sub in a single or dual 5V4 for more sag. It also has a 47 pF treble bleed cap on the treble control; no other tweed amp had this. I have seen pix of Speedy West with an early 5E8A and maybe it was designed for steel...best they could do back then.