Which (parts) of preamps & amps did John Curl design

[BrianEno]

Dear all,

I'm aware that John Curl did design Vendetta Research and Parasound products.
He also designed as an external audio consultant the Levinson JC-1, JC-2 preamps and the basics for the ML-2 poweramp.

I recently heared that he was also involved in designing/consulting Jeff Rowland frontends for an earlier poweramplifier design of them.
Maybe the WL-500 or Model 7?
Does anybody know if this is a fact?

Did he maybe also participate in anyway in other designs like Threshold or Krell?

Thanks in advance