Hello. What are the paticulars of the space you are starting with. That will enable someone to answer your question, in a way that makes sense.
Let me illustrate,
"not a studio just a room Id be able to record & be able to keep the sound out"
Ok, what is the space like, what sound are you trying to keep out? Dogs, airplanes, freeway noize, your sister? How loud? Like a jet plane? You mention six other ears. That implys you don't want sound getting out either. Keeping sound from transmitting from the outside in, is one thing. Keeping a rock band from vibrating an adjacent bedroom is another. What are you recording? And how loud do you monitor? What is the existing construction. Brick? Wood and sheetrock? Is it your home? Where in the building is the space? The basement? 3rd floor? Tell the forum what you have, so we know what your working with. Otherwise, no one can tell you what you must do, to achieve what it is your trying to achieve. At least as they can here. Does that make sense.
If I told you to build a floating room because you have a traintrack 20 ft. from the house, would it make sense? If its not your home, it would make no sense, as a rental, or property management probably would not allow it. Plus it is VERY expensive, time consuming etc. But it is one of the only ways possible to decouple the room from its environment,( for close trains) and thats IF it was in a concrete building. This most likely is not the case. Maybe you own the building. Thats an animal of a different color. These are just a few examples. There are many solutions to soundproofing. They all take careful analysis of what is "as built", and many other pieces of the info puzzle. Information is king here. If you want real help, it comes from quality information input, and information gathering on your part. You are also talking of 2 different aspects of a room where sound is concerned. Soundproofing and acoustics.
Is it bad to keep parallel walls? ETC
If you mean is it bad utilizing existing parallel walls? Vs. what? I would think not if they were brick, or concrete, or load bearing walls. especially if the alternative was moving them. If you mean building one wall, parallel to an existing wall, it depends. If your building 2 walls, that are generally parallel, it still depends. If your building an entire room. It still depends. Generaly, non parallel walls are used for 2 reasons. To defeat standing waves, and to direct reflections. If it required moving a brick wall to make 2 walls non parallel, would you do it? These are the types of questions to be considered. This was only an example. Parallel walls exist in many home studios. There are many types of acoustic treatments for small rooms with parallel walls. Remember, when you alter existing space, to do things such as build a wall, just to make it non parallel, you take up existing space by splaying it. Only you can decide if the end warrants the means. But fill us in and maybe someone can help you. I am not the expert here. Just trying to illicit info for those who are.
In the meantime, check this out
http://www.saecollege.de/reference_material/index.html
fitz
