Recommendations for HiFi Listening Room

and for cables get OCC single Crystal wire it has been proven to be the best wire for audio for over 50 years now far superior to anything ofc at any price. but again don't cheapen out.

@brewerslaw 

I hate to say this, but whatever audio equipment you bring into this large room, you will have to make some sizable acoustic treatment investment to get the best sound out of it. Make sure you set aside at least $5,000 to treat your room accordingly. Specially with the 20ft ceiling at apex, wow! Instead of talking to an audio dealer first, I would contact someone like Gik asap, give them a detail drawing of the room and ask for their advice. They will do that at no charge. As you can see in my house of stereo, acoustic treatment is a major part of the listening room.

+ 1 for a lot of what has been said already.

I’d start over.

especially the ProJect TT and Ortofon Cart.

I recently got rid of an RPM 10 Carbon. Build quality is totally unacceptable.

a good MC cart is the way to go. You need to add a good phono stage.

good luck and feel free to ask - my system is about $35 k all in - listed in detail in my profile. 

The two biggest factors are 1. The Room (you already have that). 2,. Speakers. Matching speakers to a room is not easy, after 50 years I have determined that the easiest way in a very difficult room, like mine, is to buy speakers you like the sound of either bookshelf or relatively small floor standers. Use 2 separate sub woofers, designs with built in subs may be great but separate give you far more options of placement, it is unlikely that the best location for your main stereo speakers will be exactly the same as for the subs. Then select an amplifier, 2 subs mean you don't need massive power, I use Vincent Pre / Power amps. However as the power amp is class A up to 10 watts I use a MiniDSP to cut base to the Audio Physic main speakers and direct all below 60Hz to the subs. This means my power amp never goes out of class A, and my speakers are extremely low stressed with bass. With room treatment I, in a small room have lots, however it still didn't solve the problems, the MiniDSP did. Cathedral ceilings are probably a bonus, they are far enough away from the source to present no timing issues. If the floor is carpeted then furnishings will deal with the rest. Enjoy. 

Find another dealer close by , listen to different brands.   You are spending a lot of $$$ ,  poor choices are costly.   Listen to a few different speakers and systems and put 2 subs in the budget to compensate for the room size.

It's OK to buy brand X at one dealer and brand Y at another.    No need for concessions with your budget .