Ideal design for a new music room

I would recommend you to check Pinterest for some music room design. You can see great images that you can copy for your studio. 

fwiw. Don’t try to reinvent the wheel. Rectangular rooms work and I can’t imagine why you say the Golden Ratios are hard to apply- but- you are wrong. Someone suggested 3/8 inch walls- I can’t think of a kind comment about them. Along with the Cardas site look into the construction features of the Rockport Technologies listening room. The best advice you will get is to decide the size room you want and build it solidly and symmetrically. Allow 5 -6 ft behind your speakers and at least 4.5 feet from speakers to side walls. 8 ft behind your head. Plan a vibration isolated area with a door to the side of your speakers for electronics and vibration isolation for your amplifier. Organ music right?  Assuming you’d like your speakers 6-7 ft apart you need 16-17 ft width, about 19 length. 9 ft is contemporary minimum height for a classy space. Get yourself graph paper and draw to scale-precisely. Use 2-3x5/8 drywall on walls. I’d use a base of 5/8 mdf as the first layer behind the speakers if your speakers can drive organ music down to about 30cps. I did these with my 17x27 rm and got positive comment.  Floor shd not flex. Symmetry helps to kiss. Helps resale value and decorating as well :) Enjoy and best wishes. 

I am no expert but in my there are advantages to having a dedicated listening room in the basement. 

Advantages:

1) No large windows, if any at all.
2) Concrete floor.
3) More design flexibility than if the room was in a more public area of the home. This includes the addition of acoustic treatments that only look attractive to the eyes of the audio enthusiast.
4) Easier to design such that music can be listened at high volume without disturbing other family members, especially in the late evening when the audio “magic” often occurs.
5) The option to have an adjacent equipment room to house a turntable that is well-isolated from the listening area.

Disadvantages:

1) Part of the enjoyment of the hobby is sharing music. Not many folks like to spend hours in a windowless basement listening to sonic perfection other than audiophiles.
2) If your system will include very large speakers betting them down into the listening room can be a pain.
3) Basements rarely have ceilings more than 8 feet high. This may partially be related to cost but also, the deeper the basement, the more concerns there may be with water inflow. Our neighbors rebuilt their home and deepened their basement. Their sump pump runs continuously. Our basement, less than 20 feet away but not as deep, is bone dry and our sump pump has never kicked in over the 14 years we have been in the house. 

Your idea is amazing. I have long dreamed of owning a stereo room. Wish you soon complete your ideal.
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