As far as i remember kel has jensen output caps. Not sure if there were other mods to the amp as I deleted original email from Duncan. Surely he will correct me if I'm wrong.
One thing that I have noticed is that once you have properly setup listening room the amp was excellent in details retrieval better than cambridge amp I had.
All valves are almost new so give them a bit of time run in. I have exaggerated number of hours the valves were used. Enjoy