Nasty slap echo


When i clap my hands it sounds like the ricochet sound from a WW2 documentary. I have panels on 1st reflection points but doesn't help. My room is 15x8x22, which are "supposed" to be good dimensions. I did have them drop the crown molding down 4 inches to put rope lighting up there. Was wondering if that is causing the problem. How harmful is this slap echo to the sound? Any suggestions?
streetdaddy
First reflection point panels deal with a specific issue and not with the general acoustics of the space. The slap-echo is due to the reflections from one hard parallel surface to another. Do you have a lot of hard, bare wall surfaces?
The echo you hear when clapping your hands is harmful to the sound. This can be cured with room treatment, furniture, window treatment, etc. It is best if you can cure the problem with furniture and window treatment. Whenever you add one of these items to the room continue to walk around the room clapping your hands until the room settles down. Be careful not to over do it. Too much can be worse than too little.
For the best cure for this problem, check out Michael Green's "Room Tunes" products. They will remove the slap echo without overdamping the sound. Simple small pillows you can affix to the wall to ceiling area with pins or tape. A combination of absorbtion and diffusion. Don't underestimate these things by looking at their appearance, they really work right.
Yep add natural room furnishings little by little (cushioned furniture, rugs, window coverings, decorative items, etc. to absorb sound until echoing is under control enough for things to sound good.
I have always the room was on the borderline of being overdamped. That is why i am scratching my head to this echo. Sounds like a "ping" that last for 1/2 second. Mainly at the front of the room. Will try to post some pics later tonight.
Streetdaddy, walk around the room clapping and you can pinpoint exactly the spot(s) where echo is concentrated. Treat this spot with something like the Room Tune pillows. You can make your own from fiberglass insulation and heavy duty aluminum foil as a temporary experiment. Adding treatment all over the place may be misguided and overdamp the room. Pinpoint the specific area and only treat there. Your "ping" is probably half way between corners at the wall/ceiling junction.
Agree with above posters that it needs to be addressed and can be mostly with furniture and etc. I am using bookshelves, thick carpet, rugs on the wall, fake plants, stuffed animals, basically anything to absorb slap echo. I too have walked around clapping or yelling profanities to reveal problem areas. Eliminating the reverb is especially important with rock and pop IMO due congested and compressed nature of such. Because that's mainly the crap I listen to, I have found new life in mediocre mainstream music.
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here are some pics of the room....[IMG]http://i972.photobucket.com/albums/ae206/streetdaddy/DSC_2500.jpg[/IMG]
From those pics that room looks extremely lively. I'd suggest studying up on room acoustic treatment at one of the many sites such as Ethanwiner.com or Gikacoustics.com. Plenty of good advice. Your room seriously needs it and your equipment deserves it.
Treatments made a huge difference in my room.
Funny you say that. I was just revisiting Ethan's site. I have 2 mini traps in each corner behind the curtains, and 2 minitraps leaned against the wall behind the rack. Another one on the right wall leaned on the wall just past the first reflection point.

I just took down the absorption panels on the side walls. Carpet is wool. I am thinking of making some DIY room tunes and sticking them above the crown molding in the wall ceiling junctions to see if that tames this pinging sound.

Did the pics come through for you?
Here they are again...

http://i972.photobucket.com/albums/ae206/streetdaddy/DSC_2500.jpg
Pics came though for me.
Reminds me of when I was afforded a dedicated room after our last daughter left for college. The room was totally empty when I moved in, what an echo.
How does the room sound? ...Sometimes a little echo can yield very nice ambiance to the music.
I know of at least one such room that has the most amazing bass and ambiance that I would give an arm for.
Timrhu,my first cd player was a RA cd50. What a great player...wish i still had it!
I'm not clear if the slap echo was there before you had the crown molding lowered or not.

A long time ago I remember walking downtown and entered a dome supported by columns (no walls). There was a slap echo as well that got worse the closer you got to the center. It could be the crown lowered molding can be at play here.

All the best,
Nonoise
I just looked at the picture of your room and I see why you have echo. The dropped crown molding is the least of your worries. ASC makes some absorbing panels that would work for the side walls. I would also try throwing some blankets over the leather chairs. Leather is a reflective surface that will cause additional problems.
Picture #1 link here.

Picture #2 link here.

I don't know if trying one channel at a time would make it easier to find or not. But anyway, see if you could have someone walk around holding up a large bath towel (stretched out of course), to try and block that reflection. I'm thinking one channel at a time may be easier, but not 100% sure. Leather is bad for reflecting. If I wear a leather coat, I can hear all kinds of reflections off of it, in comparison to something soft and more absorbent.
Thanks for the help guys. I will try these one at a time when i get a chance and see what helps.
I guess i should have labeled this thread nasty slap "ping". I know when i clap in other rooms i hear an slap echo. This is a different sound altogether. Really weird.
I have a set of first reflection point absorbers from realtraps, but they do nothing for this sound. I removed them a few days ago thinking maybe i had my room overdamped.

May try to get some insulation and make some DIY rolls to set on top of the crown molding. Does it matter what R value? What have you guys used to roll them up in? Some kind of black fabric would work best visually. I could have my wife sew some tubes and stuff them, i guess.
Thanks for the picture links. Hard to really hear it when music is playing. My wife is off today so i will have her clap at the speaker locations and see how bad it is in the sweet spot.
When i walk around the front part of the room clapping my hands it is really bad...clap.ping...clap..ping.
"How does the room sound? ...Sometimes a little echo can yield very nice ambiance to the music. "

That's an important point! It's always useful to understand your room's acoustics and how they are working, but a "slap echo" may be a good or bad thing depending. I've heard some very lively rooms at dealers not unlike yours with significant "slap echo" sound uniquely engaging and lifelike, even quite holographic (in a good way) as opposed to the opposite, ie dull and lifeless!

Even if you can reduce or change it temporarily and listen as a test first using whatever means available, that would be useful prior to making any permanent changes.
Streetdaddy, Instead of clapping at the speaker locations you should be clapping where you listen from. If you want to make this simple put your system on the long wall and you will only need to treat the wall behind your head. Unfortunately you will have to sit beside each other like normal people, but you will have a broader sound stage and you won't have to worry about side walls. You will get a bigger sound stage, better midbass, less room interaction, less room treatment required and you get to sit next to your wife.
BTW legend has it that the original Three Stooges has slap echo down perfectly in their listening room.

Curly: "A whooba whooba"!
Moe: "Shaddap and listen!" Slap!
Larry: "Leave him alone"!
Moe: Slap!
Curly: Nyuck Nyuck Nyuck!

You get the picture...
Oh man, that's an empty room, bare walls, nutten' to diffuse/deflect sound waves...hang some pictures/paintings and or heavy drapes to break up all that empty wall space.

I can imagine the echo in there being too much, like speaking in a big tunnel.
Really, leather is a problem? In my well treated room my leather couch and chair have no negative effect. I think leather is a non-issue to be frank.

Perhaps metal folding chairs are a bad idea:-)
Grannyring, Is leather a reflective surface or not? Listen with your head against the back of your leather chair then place a blanket over the chair and listen again. If you can't hear the difference then I guess it is a non-issue for you, but I can tell you it is an issue for me. It has the same effect as having your chair close the back wall only milder. If you don't want to go through the trouble of getting up to get a blanket just lean forward a little and tell me if the sound doesn't clear up a little.
Oh jeez, now I gotta go and check my comfy Scan leather swivel/recliner I've been using for years to see if it is mucking up my sound....:-)
Rrog,

No, my Ekornes leather audio chair is not an issue. I suppose if the back went clear up to the top of my head it may be an issue. It does not.

I also have a leather couch in the room. I suppose I should a/b verses a cloth couch.

My room has many GIK absorption panels so I suppose the leather may be a good overall balance. Don't know, but the sound is very, very good indeed.
Rrog,

Question for you and others. Does the leather on my couch cancel the frequency absorption properties of the mass beneath it?
Oh jeez, now I gotta go and check my comfy Scan leather swivel/recliner I've been using for years to see if it is mucking up my sound....:-)
Mapman

You say that in jest, but if the top of the chair is above your head it does affect what you hear.
A few years ago my wife bought me a very nice leather chair for my birthday. When I picked up a low-back chair at a garage sale for $5, I was afraid it would hurt my wife's feelings if I moved the expensive chair to the side. The $5 chair made a significant improvement in the sound so it stayed.
Has anybody ever made some DIY "room Tunes" using Owens Corning 703? I was thinking of picking some up and sticking it in the corners and maybe ceiling wall junction points.
"You say that in jest, but if the top of the chair is above your head it does affect what you hear. "

Yes, in jest, and yes it is above my head (when not reclining) and yes can no doubt affect what you hear, leather or otherwise FBOFW, due to proximity to ears.

A cheap easy tweak to experiment with....
Streetdaddy,
Yes all of my treatment is homemade. it's very easy to make. I used rockwool not 703 - much cheaper and works the same. Make a frame the size you need, place in 703, wrap with a breathable material and hang on the wall.
For higher freq. you can use 2 - 4 inch 703. To absorbe lower use thicker 703 -multi layers, Keep the back open, no backing to the frame and when hung have the trap way from the wall to increase the efficency of the traps.
You need them at the first reflection points, and as bass traps (thicher ones)in the corners.
That will be the starting point. From there you can add to it if needed. Also measure the freq response of you room usng REW. You will be suprised to what you actually are hearing