Bass echo?

[rs159]

I've tried literally about 20 different placements and none seem to fix this problem I've been having. It's hard to describe, it's like there is a certain corner or entire side of the room where all the bass kind of sneaks over to. I've got it to the point where it isn't directly audible, but you can definately notice that one ear is experiencing greater SPL than the other in the bass. The lower the frequency, the worse it is. I've tried hundreds of recordings so I know that's not the way it's supposed to be. I'm extremely frustrated and nothing I try seems to work. The room has a hollow door in the corner, could that be the culprit? I did notice one time that in one corner the bass was completely out of control and in the corner with the door (along the same wall) it was anemic. The room is 10' x 11' x 8', cubic, eek.

:supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad: :supermad:

[danger boy]

an echo as you call it could be from the lack of things in the room. is your room pretty sparse in terms of wall coverings, carpet, furniture?

do you have the sub volume turned up to high? Did you sent the sub volume with a sound meter?

typically your sub should be placed along the longest wall... in your case.. of of the walls that is 11' long. Thats where mine sounded the best.. it also just happens to be next to my couch.. so it shakes the couch. so you feel the bass going thru the couch and your ass. :lol:

[rs159]

No, it's a typical bedroom filled with stuff. The corner where the door is also has a small built in closet on the adjacent wall that is filled with clothes. A bed is in one corner, and a dresser is in the other. The remaining corner has a display case filled with collectibles and things, so I wonder if putting something with more mass in that corner would clear things up?

It's not an echo per se, but it's almost like there is a second "ghost" sub along one wall or something.

This happens with my mains too, so just changing the sub position wouldn't do much. I tried playing some FM radio in mono mode, and everything was dead center except the bass, which was a few feet to the left. Deeper frequencies went completely away fromt the speakers to a certain corner of the room. It seemed like the right speaker wasn't playing bass at all and it all was migrating to the left.

Interestingly enough, the effect was more pronounced with the windows open.

This room has given me nothing but stress since the day I bought the beginnings of my system, that's why I'm moving into the basement soon. But I will put another system in the bedroom for TV and background music, so I will still have to deal with the same problems.

:supermad:

A very stressed RS

[rs159]

BTW, I don't want to move the display case. Since I will move the real system to the basement soon I tried to make the room look as good as I could with audio as a secondary consideration. It actually looks pretty slick, there is a window beside the big display case and below the window there is a matching smaller case. It has a real "built in" look.

RS

[danger boy]

ok. lets start from the beginning.. please list your system. begin with the receiver, speakers, cables, sub type, and we can go from there.

I think you may have your speaker(s) out of phase.. check to make sure all your speakers are plugged into the pos (red) and the neg (black) inputs. one wire that is crossed can cause a speaker to shift the bass out of synch.

[rs159]

I'm 110% sure it's not phase. That's one thing I always check. It's a simple stereo receiver with no sub output so bass management is not to blame. I also disconnected the sub so that is not to blame either.

I think I have the problem solved by now by moving the listening position closer to the wall behind the chair. One thing I *always* noticed reguardless of where I put everything is that the middle of the room always sounds anemic. Damn cubes. I think all those crazy standing waves and such crashing into eachother right in the middle of the room can create some very weird effects so I'm just playing around with the speaker placement with the chair about 1.5 feet from the wall. That solves most of the problems but it was a bit boomy at first so I'm still experimenting

[danger boy]

another good place for your sub is in the front of the room.. either to the side or inbetween your fronts.

[MxStYlEpOlKmAn]

RS, Buy a giantic cover a really heavy one, and when you want to listen to music put it in the corner, when you don't take the gigantic cover away. This helps my bass response in my room.

[rs159]

MX, Like a blanket or something?

I've actually gotten it pretty smoothed out by this point but being a tiny cubic room with tons of furniture there are still some issues I have to hammer out. I might just go down to the rat shack and buy myself an SPL meter to see what's really going on. Make a grid of the room and measure the SPL in each square foot. First using one speaker, then two to see if that has anything to do with it.

"Damned! this hobby is so much fun that I can't hardly contain myself... :p " - polkatese

[rs159]

Shit, I just had a retard moment. I forgot that these problems exist in THREE DIMENSIONS! Looks like I'll be quite the busy one with the SPL meter.

[danger boy]

for any serious set up..whether in stereo or multichannel... a SPL meter is important. every time I lend mine out to a friend.. they're impressed with how the sound quality improves once they're finished. i should start charging em for the use of it. :p

[Vr3MxStyler2k3]

Originally posted by danger boy
for any serious set up..whether in stereo or multichannel... a SPL meter is important. every time I lend mine out to a friend.. they're impressed with how the sound quality improves once they're finished. i should start charging em for the use of it. :p

After I get all Adcom amps I plan on buying a SPL meter to calibrate, right now my speakers sound ENTIRELY different. One more Adcom to go and I'll be there. Right now I need to go to Ratshack and buy cables to plug the amp up with! I need Banana plugs too so I can use 12 guage wire! Yeah Rs, I mean a huge arse cover, really thick. It can dampin the sheat outta sound. Try it with a cover at your house and if it works well I would suggest buy a thicker cover if it works out, other than that, its one of those cheap substitutes!

[rs159]

Sounds like a temporary bass trap to me. I see how it could help. One day when I'm not lazy I'll try that.

[danger boy]

Sid why would you want to buy RS cables? there are others out there that aren't that much more than Radio Shack. try AR if you don't like Monster. i would think other entry level cables are better than anything RS sells. (sorry if anyone here works for RS).

[Vr3MxStyler2k3]

isn't Entry level AR like 30 bucks? lol! Well I am getting a 6 foot cable for 10, suits me. I would get their fusions, but way out of my price range. Mid level system, low level cables and wire.

["Polk" Paul DiComo]

It sounds like you have two problems: first you are experiencing the results of standing waves - the way the bass waves interact with the room. It is a function of the dimensions of the room. The closer the room gets to being a perfect cube, the worse the problem will be. Ther are ideal dimension ratios for rooms but those damn home builders just aren't audiophiles so they don't know what's really important!

You may find some helpful advice on these links

http://www.polkaudio.com/home/faqad/advice.php?article=placement

http://www.polkaudio.com/home/faqad/advice.php?article=subsetup

Ken in Polk customer service has a nifty program that helps find the right speaker and listener positions that yield the smoothest bass. Give him a call at 800-377-7655.

Second, you may also be having a problem with room surfaces that are resonating - not to the point of buzzing but enough to reduce bass at some frequencies and increase it at others. If your house is on the new side it probaly doesn't have stiff walls. Read this whole article for more help.

http://www.polkaudio.com/home/faqad/advice.php?article=optimizeroom

Good luck.

[tperio]

i"ve got to much echo and static how can we fix this

[danger boy]

echo? are you using one of the DSP modes on your receiver.. such as hall, or church, or stadium? those will all give you echo. turn them off if one of them is turned on.

as for static... please explain in more detail what it sounds like.. what equipment you have, the layout of your room. this all helps in determining the cause of the problem.

Please also understand.. that most of the folks in here are other lovers of music and home theater.. we are not employees of Polk Audio. we just love their products. :p

[rs159]

Paul, I know my problem is standing waves. Cubic room, makes sense, and my experience with the room backs it up. I'm about so pissed off with this room by now that I decided the only thing it's good for is my $80 Sony boombox. I've actually been listening to the headphones on my computer more lately because the real system sounds like hell in the room. I do NOT want to deal with this room from hell anymore, so I'm not even going to try. I'm sorry I wasted all your time, but I guess I at least learned that you can't make bad dimensions sound good, aside from tube traps and all that stuff which if you have a non ideal room you probably have too much stuff in it anyway to apply treatment.

[Airplay355]

i use a lambs skin thing in a corner of my room because the rti100 woofer is close to a corner and a wall unit makes the bass even stronger, bass sounded hollow and boomy before i added this, it actually looks nice on the ground behind there and covers up wires coming from the basement and the speaker and AC cords of the speaker :) worth a try i guess....i was thinking about hangint 1 or two on my back wall to absorb sound

[burdette]

Hey RS.. I really think I'd try hanging up some material before you give up on your better system. Even if you go to Salvation Army or military surplus or whatever, just get 2-4 heavy blankets or old sleeping bags. Experiment with placement. I'd think places to start would be: behind the sub, on the wall opposite the sub, and, if you can, diagonally across a corner or two or slanty from ceiling to wall. There are worlds of differences in rooms due to carpet, wall hangings, etc. Work with that and see if you can use it to your advantage. Might look strange, but you could try the foam egg-crate mattress pads at WalMart. I don't think the larger ones (full, queen) are pink like the twin size.

Have you tried raising the sub to a different level? Perhaps lifting it up a little.. put it on cinder blocks or something.

[Tour2ma]

True, deep bass, < 100 Hz or so, is virtually unkillable. But frequencies aboive 100 Hz can produce standing waves as well. Room treatments, blankets, etc., will absorb increasing percentages of sound energy as frequency increases, but will do very little to manage deep bass.

rs,
Room treatment may help, but you may be able to find a fairly neutral combination of speaker and head placement in the room as it is. The only place the spl measurement really matters is head level at your listening position.

What test tone sources will you use for the spl check?

[rs159]

I moved everything to the basement last week. The speakers are placed so the soundstage is not parallel to the wall, but rather putting the center image a bit to the left of the corner. The TV is placed accordingly, a bit out from the wall and at an angle, and the sub is close to the corner, next to the area behind the TV. The chair is about 3 feet from the wall, also at an angle. I know there must be some nasty reflections given the chair's proximity to the wall, so I will hang some blankets, w/e later. I found that sitting the sub and the chair dead center in the room will *SUCK OUT* any and all deep bass. This might not be the final setup, as I still haven't recovered all of the deep bass (but it's a signifigant improvement), and I want to open up some space for the surrounds.

Tour, I "homemade" all of my test tones. I used a computerized test tone generator to make discreet tones that go from 200hz to 100hz in increments of 5hz, and from 100hz to infinity in increments of 2hz. There are also some sweeps.

I might move soon, so I'm not bothering to fix up the basement. I will definately look for a house that has effin sloped ceilings!

God, why can't I be into car audio?!?!?!?!?!