I have Zeroimpedance.com naked Autoformers with 8' of crimped-on Anticables-- both manufactured by Paul Speltz and available on 60-day trial. This Autoformer has 2x, 3x, and 4x taps.
I had best results with WPs & Autoformers & mid-powered tube amps like BAT VK75SE and ARC VT130. With these amps there is a big improvement in dynamics & bass control with very little affect in the mid & treble regions. Even 120wpc is really not enough power for WPs without Autoformers. With Autoformers, amps in this range sound like big monoblocks.
With Autoformers & low-powered SETs, the improvements come with the cost of a slight loss of SET "magic" that may or may not be acceptable to you. Still, Autoformers are nice tools to have around when testing & matching amps to difficult loads.
I had best results with WPs & Autoformers & mid-powered tube amps like BAT VK75SE and ARC VT130. With these amps there is a big improvement in dynamics & bass control with very little affect in the mid & treble regions. Even 120wpc is really not enough power for WPs without Autoformers. With Autoformers, amps in this range sound like big monoblocks.
With Autoformers & low-powered SETs, the improvements come with the cost of a slight loss of SET "magic" that may or may not be acceptable to you. Still, Autoformers are nice tools to have around when testing & matching amps to difficult loads.