I do a lot of goofy things when I'm bored, like building a chair out of rescued Plexi and bolts, making a low "art table" from aluminum-wrapped concrete blocks and a plate of 1/2" glass, or write short poems. However, this is the recording forum, so never mind all that. I have a virtually unused Marshall Class 5. I live in an apartment building with thin walls and a few crabby tenants, hence the "unused" descriptor. It has a headphone out so you can blow out your eardrums without the resulting visit from the local constabulary. I know that a line in can handle a headphone output if you keep the level low on the amp but I hesitate to run a tube amp without some kind of speaker, even with the attenuator. I thought that since headphones ARE speakers, and I have a couple of dummy heads (don't ask), why not bore a 1" hole on each side of the head, and stick a microphone up through the bottom (neck). Plug the 'phones into the amp and clamp 'em on the head, and connect the microphone to the mixer. The heads are made of somewhat thick plastic, so there might be some echo, but I can stuff something in there to dampen that if needed. OR, just tape the headphones to a ball head mic. I thought there might be some ambiance feature of the head, though. This might be one of those things that is just dumb enough to work. The chair and the table worked out OK.