I would doubt it much. Your amp has quite a bit of gain. I really liked mine with 6550 but you have to be careful. Winged C worked for me. You can try this. From a thread I posted long ago.
If you insert a patch cable from the FX rack send to the FX return, jumpering the loop, your amp will turn into a monster from the hotter signal post PI and power amp I believe.
****** Some of the earlier white head Shivas are mislabeled like mine. When Bogner designed the new tubes up Shiva 20th they forgot to change the rack send and pedal send labels on the chasis. My amp's rack send is actually my pedal send and vice versa. This is why I thought I was getting such a huge volume increase by jumping my pedal send to return. It was making no sense to me since the rack send should be the hotter signal. If you jump the rack send to return look out. It gets loud. Charlie at Bogner just cleared it up for me. He said it's one of those embarassing things like a misminted penny. They only caught it fairly recently. Pretty cool info.