The need to build a cage in my basement ?

Hello, I m'gonna live in a new constructed house with no direct neighbours. I only have 1 neighbour at 30 feet from our house. I want to record & rehearse in the basement. This means the presence of a drum and some tubeamplifiers ... so .. loud. The house plan is showed as attachment. I have 1 room in the basement that is very clean and "nude" ( sorry , I'm french speaking). Tiles on the floor, big grey brick as walls. It sounds like a bathroom ... and looks like it too. The room is 13ft on 20 ft (height: 7ft ... not much). Like on the plan, you can see that 2 walls are on -1. Meaning that these walls are well isolated because there only is ground on the other side. It's difficult to explain ... the whole basement is not under the ground ... the right side of the house begins at level0 ... and the left side of the house starts at -1 ( garage). The 2 other walls are connected with the garage and the washroom ... So even if the music is too loud in these rooms ... I don't care. My only problem is the sound that goes to the neighbour. I thought ... I'm gonna buy a lot of material and build a cage in a cage like I read in the forum ... problem is ... I only have a height of 7ft ... and our bass player measures 6ft. So, making a floating floor and a hanging ceiling is not an option. And some people say that it is not advised to play loud music in a 6ft room ... that the acoustic treatment will be expensive on that matter. So, I was thinking. Is it a good idea to only isolate the ceiling, and the 2 walls that are not surrounded with the ground, by putting a stud construction in front/beneath it, with rockwool behind it, and isolated with rubber/neoprene from the ground ( like others in this forum) . The the other walls would then be treated with foam and self made basstraps. The floor would be coverd with carpet ... and drums + amplifiers will be mounted on neoprene/rubber tiles + wooden plate. Concerning the door ... i will build a wooded frame in the stud construction in order to have two doors. Will this be enough to isolate the sound in order that the neighbour doesn t hear anything? In other words ... is it usefull to only treat 2 walls out of 4 ? Maybe the vibrations from the non-isolated walls will pass behind the stud construction because the 4 walls are connected ... I don't know. Is it usefull to put a hanging ceiling if the walls and floor are still "nude" ... :) PS: If a place basstraps and other absorber in the room ... will this also diminish the sound volume that comes outside the room ?

have you measured how much sound is coming over to the neighbors? maybe kick on the PA really loud playing bass and drums and use a sound level meter to see whats actually happening... this way you'll have n idea about how much isolation you need. it may be that the ceiling is the biggest source of sound leakage vs the walls (which are underground), or any basement windows.