Very sincere apologies in advance if I'm not posting in the right place for this! I'm endeavoring to understand for myself first what I want, then will go looking for a professional to install.

I have an early '70's ranch home - single story - 1,600 sq ft. 3 bd / 2 ba. I have a ~06 Goodman central air conditioning system.

My complaints are that the entire system is noisy - and we run the system all night to keep the bedroom cool, which is very inefficient... and again, noisy.

NOISY SYSTEM: There doesn't seem to be any mechanical noises that would suggest that the system is "broken" - however, the design of installation is likely causing louder than desired fan and air circulation noise. We don't hear the outside condenser unit - it's the air circulator that appears to be making the noise.

• NOISE DUE TO AIR CULARTOR LOCATION / DUCT DESIGN? The air circulator is installed in a closet in the garage that shares a wall with an interior hallway that leads to the utility room and master bedroom. The HVAC closet has a raised floor, and one of the air intake returns is ducted right below it to a ground level return grate in the interior hallway just described. Would placement of the air circulator somewhere else more removed than directly over the air return help with noise? (i.e. the attic?)
• NOISE DUE TO SINGLE SPEED AIR CIRCULATOR? This Goodman HVAC system seems to be single speed. Would a more modern variable speed system be much quieter and more efficient? Is one brand known to be more quiet than another? Anyone have experience with a Mitsubishi Ducted Air Handler?
• DUCTLESS MINI SPLIT IN MASTER BEDROOM? Ever have customers install a ductless mini split in one room, like the master bedroom simply because this one room is run all night most of the year, and cooling a single room vs whole house for extended periods is more efficient... and may be much quieter too in my case!? - as I mentioned, the noisy return is right outside the master bedroom.

WHOLE SYSTEM REPLACEMENT? What about a whole system replacement? What about a new modern variable speed system? Would the current air circulator location and duct design mean no improvement with a new system - even a variable speed one?

• How much would a modern, quiet, variable speed whole system replacement cost? What brands are recommended?
• What about a modern, quiet, ductless hybrid system from a manufacturer like Mitsubishi? This would mean, perhaps, ductless setups in each of the 3 bedrooms - and ducted for the rest of the house. Are these more expensive?
• ....other options?

...this is a big post. I've never before given this much thought to HVAC in my life. We just purchased a new house in an up and coming neighborhood, and are trying to decide what to do to make things more comfortable... within reason.