The thought of building an aa1164 has been festering in the back of my mind for a while now and seems to have become more insistent since I finished my last project. I've had three possible builds in mind for my next project: a PR, an octal deluxe, or a single ended el34 thing more of my own design that I've been kicking around in my head for a while. The SE el34 idea still doesn't quite feel fully baked to me so I want to put that off and let it gestate a while longer and the idea of a Princeton build is eating at me a lot more than the 5c3, so that is where I think I will end up going. Anyway, I was planning on doing a straight aa1164 with a Hoffman layout, but looking Hoffman's site got me thinking about his non tremolo version. As much as I like on board trem in theory, I find that I rarely use the feature on either my silverface vibrolux reverb or my brown hybrid build. Both have great tremolo and I love the sound, but it isn't really something I use. It also seems that bias vary tremolo in particular has the inherent problem that it makes you either bias for the tremolo or for the amp, but they each have a different ideal setting. Since removing the tremolo from the aa1164 circuit has no impact on the function of the rest of the amp, it seems like the non trem version would be better for me. Removing the tremolo frees up a triode and two control pots, which really speaks to the part of me that can't leave well enough alone... So, I'm thinking of using one pot as a "fatness" control to fade in that spare triode as a parallel on one of the gain stages, probably the second one, but I need to think about where it would make the most sense. I also like the idea of putting a PPIMV in that other unused control spot. I also think I may replace the footswitch jacks with a passive fx loop. I don't feel the need to be able to use a footswitch for the reverb and part of the reason I want to build this amp is its reputation for being pedal friendly so this seems like a useful feature for me. TLDR summary: I'm thinking about building a blackface PR clone, but with no tremolo, an adjustable parallel triode on the second gain stage, a post PI master volume, and a passive effects loop instead of foot switch jacks. I think all of this will add more options to the amp but as far as I can see none of it should effect the sound of the classic circuit when not in use. Thoughts, opinions, criticisms and suggestions please!