Air conditioning for audiophiles.

Hi, i happen to be an HVAC professional and audiophile.  Ductless would be ideal with sound levels in the low to mid 20 dBA when running on low speeds.  We have installed them in recording station studios and especially with near field microphones they can't be detected. However, they could be very difficult and expensive to install in an apartment.  You might consider putting your window or portable a/c in another room, preferably a larger area and letting some of the capacity and dehumidification filter into your music room.  If it's more of a studio setup, then try to get distance between the A/C to your listening area.  You Should be able to shut the a/c off during you listening sessions and get an hour or two before the temp and humidity get unbearable.  If you find it get's uncomfortable even for a short period with the A/C off, you really should focus on reducing the infiltration likely thru leaky windows and reducing solar heat gain likely thru old windows with no radiant barrier. After that, it's over the ear headphones!!! 

Hi,

you can also look into Maestro series by i think Unico.  2) 8"0 holes thru the wall instead of the traditional thru the wall PTAC style.  Inverter Driven Variable Speed, very quiet, fairly expensive when all things are factored. Warning - new to market.  If it fails or the parent company or likely Chinese manufacturer abandons product due to problems you will be left with Two 8 inch holes in your wall.   

Do you have any tube gear?

If you use a box fan make sure you exhaust air to the outside. And on low they are fairly quiet

@jond 

FYI,  I have a one ton Mitsubishi split that instead of taking up wall space like a hotel unit, is installed between the rafters and all I see is a plastic grill in my ceiling.  Anyway it was expensive, but is fairly quiet on it low and medium speeds. It does good job of cooling and an OK job of heating the 330 square foot room it’s in.