[Early B.]

I have an enclosed patio that is roughly 23x12 and three sides are comprised of 38 linear feet of 4 ft. tall windows. There's a patio door that's also made of glass. On top of all of this (pun intended), there is a sloped ceiling that starts at 8 ft. and ends at 12 ft. Oh, and the floor is stone tile and the room is mostly empty. As you can imagine, it echoes like crazy. Here are my goals:

-- I want to decrease the echo as much as possible without spending a lot of money.
-- If needed, I can create removable acoustic panels that can be propped up on the windowsills to cover the windows
-- the solution doesn't have to be aesthetically appealing, just functional.

Here are my questions:

1. What is the biggest contributor to the echo -- the windows, floor, or the sloped ceiling?
2. Is there any benefit to setting 1/2" or 3/4" 4x8 wood panels in front of the windows to reduce the echo?

Thanks.

[JLM]

Absorb opposite surfaces (ceiling, end wall) with GIK panels (something designed to absorb, not just looks like it should).

Setup should be along the length of the room with speakers roughly 5 ft from one end and the listening position roughly midway. 

Room dimensions aren't bad, just too many hard surfaces.

[SlushPuppy]

In my last house with an entire wall of windows, I had great success with acoustic curtains. You'd be surprised how cheap they are compared to professional sound treatments, and you can get some that compliment your room. They also block summer heat.

https://www.amazon.com/Soundproof-Curtains/s?k=Soundproof+Curtains

[Letitroll98]

Please don't take offense as I consider you one of the bedrocks of our community.  But my first suggestion is to give up these ill conceived ideas.  In addition to the issues you so clearly detailed, the walls and window frames of most porches are usually much less robust than in the main home, adding to resonenses and vibrations.  While a lovely sitting area it's just not an audio friendly space.  My thought is a quiet space for meditation.

However in the interest of being positive I'd reduce the space, both in area and frequency response.  Make the listening area a smaller rectangle near the TV and ignore the rest of the porch, creating a nearfield listening environment.  Then you need only treat a much smaller space.  Reflections from the other side of the room should be delayed enough to not destroy the nearfield soundscape.  And use small monitors that cut out anything below 50-70hz.  Bass is the enemy of small rooms.  Maybe a soundbar?  Best of luck.

[Early B.]

While a lovely sitting area it's just not an audio friendly space.  My thought is a quiet space for meditation.

I should have mentioned that this space will NOT be used to place an audio system in it. Ironically, it will be used as a quiet space for meditation and as a sitting area for discussions with friends and family. Even for talking, the echo is annoying. That's what I'm trying to resolve in the cheapest way. 

[Early B.]

In my last house with an entire wall of windows, I had great success with acoustic curtains. You'd be surprised how cheap they are compared to professional sound treatments, and you can get some that compliment your room. They also block summer heat.

https://www.amazon.com/Soundproof-Curtains/s?k=Soundproof+Curtains

Excellent idea!! Thanks.

P.S. -- geez!!  I just spent $700 for soundproof curtains. When I said, "cheap," that's not quite what I had in mind. Nonetheless, I'm sure the wife will prefer curtains over any other acoustic window treatment.

[qdrone]

Drapes or floor length curtains.

I put a blanket over my breakfront glass.

[VinceT]

Even for talking, the echo is annoying. That's what I'm trying to resolve in the cheapest way.

Ahh, the audiophile ears pick up on those reflections and now you cannot unhear it and relax.

[toocool4]

Your floor area looks like the largest reflective area in that room, so unless you are attached to that floor, I would investigate getting carpet to cover the floor. The total area of that floor is larger than your windows area combined.

[mick wolfe]

Your floor area looks like the largest reflective area in that room, so unless you are attached to that floor, I would investigate getting carpet to cover the floor. The total area of that floor is larger than your windows area combined.

I agree. A nice area rug would go a long way in taming the room.

[rollo]

 Lots of reflective surfaces. Tile floor, glass and painted walls. That room would be a challenge. You can make it work just some demo and different materials choices.

charles

[Early B.]

I agree. A nice area rug would go a long way in taming the room.

Yeah, I may as well buy a thick, comfy area rug because my wife may make me sleep on it. She didn't even want curtains, but man knows best.

[JakeJ]

I'll throw my .02 in the pot.

The large surface area of the ceiling is also part of the problem.  Some treatment there as well?

Maybe these?  Or these for diffusion?  Again for diffusion on the cheap.

Hope the project is fun.  If there is a view out those windows I would be loathe to cover it up, but that's me.

[Tyson]

If you don't mind a bit of DIY, these are nice and cheap and come in a variety of sizes - https://www.dentonwoodworkers.com/shop/absorption-frames-kits/2?page=1&limit=60&sort_by=category_order&sort_order=asc

[g3rain1]

I agree. A nice area rug would go a long way in taming the room.

I would actually disagree here.  Due to the non-parallel surfaces, the floor/ceiling direction is contributing less to the echo of the room than it would in a typical room. I'd focus more on the walls here. Yes a rug would help, but not as much as typical.

If I wanted to tame that space as cheaply as possible without altering the ascetics much I'd go with some DIY panels on the house side of the room. Some wall insulation batts (rockwool or fiberglass) in a wood frame covered in a fabric, then hung up with either picture wire or saw tooth hangers. A half dozen panels could be made for under $200.

[Early B.]

So far I've done two things -- purchased super thick curtains for the windows and a huge area rug with a 1/2" thick pad. I agree the rug probably won't make much difference sonically, but there's a wife to keep happy. I'm in the process of installing the curtains and will report back once it's done.