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Willow
01-09-2004, 06:01 AM
Will this cause a problem if the rear speakers are rear ported ? can they be wall mounted or do they have to be on stands ? If they do need to be on stands shoot those will be tall ones for sure. ( talking about bookshelfs ) any other suggestions on how to get them up there (the ideal rear listening position). My rears are on unstable stands right now and as you read they are rear ported. what to do ? I dont want to screw in shelves in the walls (rental property) the stands we are currently using are telescopic and can go as high as 4ft with the tweeter at about 4.5 ft ( but not very stable they are leaning against the wall fo extra support)


Thanks

markw
01-09-2004, 06:10 AM
Rear ported speakers cannot be mounted directly against the wall. No harm will befall them, but they need to be at least 6" (or more, depending on speaker, check your manual) or else bass will be seriously degraded. Likewise, the rest of the range might sound a little funky as well due to the imbalance.

Now, if you can somehow mount them on arms that will keep then off the wall...

INHSHO, I find it ludicrous (sp?) to call rear ported speakers "bookshelf" speakers simply that term implies mounting on a shelf, most likely against a wall.

Then again, I can remember when a "portable" color television weiged over 50+ pounds andthe only way itdiffered from a table model was the flimsy "carrying handle" on the top. Woe to those who ever tried to actually use that handle. (Can we say "hernia", kiddies?)

Willow
01-09-2004, 06:54 AM
I thought so. After checking out the DD website im going to try putting them on thier backs right behind the seating firing upwards as depicted in 12B
http://www.dolby.com/ht/Guide.HomeTheater.0110.html#s3.2 seems to be the alternative for right now. Will placing a speaker near not over top of a heat source (baseboard heater) cause a problem or mess up the speaker ??

markw
01-09-2004, 07:02 AM
Good thinking to be concerned about this.

I had to refoam/recone a 14" JBL woofer after it was close to a heat source for less than two years. Of course, the heat was not on all the time (This is new joisey, not the north pole) but it did kerfutz up that nice rubber surround enough to make it brittle and fall apart.

Then again, this was a forced air system but, just in case, I'd try to keep them as far away from heat as possible. ...and sunlight as well.

Willow
01-09-2004, 08:16 AM
good to know...but geez if it's not one thing its another...no wonder my wife gets bothered when I start playing around with the system. I may resort to having them sit on the end tables but bookshelvs are not cubes....wish more speakers came with a design like polks power ports !!! now thats a good idea

Tarheel_
01-09-2004, 08:59 AM
can you mount them against the wall and increase the freq. crossover at a very high level and let most/all the bass go to your sub? I have rear ported speakers mounted onto a wall, but they are polks and have a 2" gap...I have the crossover set at 200hz...going on 2.5 years without problem and i listen at med to high volume. Just a thought....

Willow
01-09-2004, 09:07 AM
can you mount them against the wall and increase the freq. crossover at a very high level and let most/all the bass go to your sub? I have rear ported speakers mounted onto a wall, but they are polks and have a 2" gap...I have the crossover set at 200hz...going on 2.5 years without problem and i listen at med to high volume. Just a thought....

I could do that well thats what I am doing my rears are set to small but the JBLs I have for rears the port is flush with the back therefore flush with the wall. Come to think of it they don;t even have prefab holes for the wall screws....guess that answers my questions..keep like they are or try the way DD suggests with them facing upwards with the port firing towards the floor. this can be done with the stands I have and it may be more sturdy.

Tarheel_
01-09-2004, 09:53 AM
I could do that well thats what I am doing my rears are set to small but the JBLs I have for rears the port is flush with the back therefore flush with the wall. Come to think of it they don;t even have prefab holes for the wall screws....guess that answers my questions..keep like they are or try the way DD suggests with them facing upwards with the port firing towards the floor. this can be done with the stands I have and it may be more sturdy.

here is another idea...my polks came with rubber stoppers to extend them from the wall. Perhaps you can find some at Home Depot, etc... glue them on...and at the same time you can purchase some type of bracket...attach it to the speaker and then locate a stud in your wall. Drive a screw directly in the stud and mount. Thats basically what i did...cause the wife likes them wall mounted and they are above my listening position.
Not sure if you listen to multichannel music, but the speakers facing upward will not work well. Just more thoughts..

Willow
01-09-2004, 10:02 AM
here is another idea...my polks came with rubber stoppers to extend them from the wall. Perhaps you can find some at Home Depot, etc... glue them on...and at the same time you can purchase some type of bracket...attach it to the speaker and then locate a stud in your wall. Drive a screw directly in the stud and mount. Thats basically what i did...cause the wife likes them wall mounted and they are above my listening position.
Not sure if you listen to multichannel music, but the speakers facing upward will not work well. Just more thoughts..

might try that but how did you hide your speaker wire ?...and we don't listen to lots of music on it mostly radio or plain ole' cd's

topspeed
01-10-2004, 12:05 AM
A couple of ideas here Willow,

First, you might try ditching the stands and wall mount them, if your layout permits. I have these brackets and I like them because
1) I didn't have to drill into my speakers (the thought of which drove me crazy)
2) the bracket is strong enough to hold up a Hummer. It should also place your speaker far enough away from the wall where the port will have enough room.
http://www.crutchfield.com/cgi-bin/S-Sa5Mbjw4UMm/ProdView.asp?s=0&c=1&g=110700&I=121BT77B&o=m&a=0&cc=01&avf=N

Second, you could always just plug the ports. B&W actually supplies foam bungs for their flowports for situations much like yours. By installing the bung, it eliminates chuffing and the like when placing the speaker in close quarters or too near a wall. Bass is diminished of course, but at least you don't get weird noises. Keep in mind, you have to really be pushing your speakers to get enough air moving where chuffing becomes noticeable. As your surrounds, I doubt they ever get enough signal for that to be a concern. Multi-channel hi-rez is another thing altogether...

Good luck and let us know how it works out.

recoveryone
01-11-2004, 12:56 PM
I could do that well thats what I am doing my rears are set to small but the JBLs I have for rears the port is flush with the back therefore flush with the wall. Come to think of it they don;t even have prefab holes for the wall screws....guess that answers my questions..keep like they are or try the way DD suggests with them facing upwards with the port firing towards the floor. this can be done with the stands I have and it may be more sturdy.


My rears have rear ports, but where I have them mounted does not effect the sound. Also in the Dolby setup page shows mounting the rears high on the back or side wall then add a slite tilt downward to give the room needed for the rear port

joel2762
02-07-2004, 04:32 PM
I have rear ported speakers. They're on stands, the part of the stand that they're attatched to is a cirle shape and blocks a bit of the port. There's a bit open but not alot. They still sound fine! BTW: What's a Polk Power Port eh?

Mr Peabody
02-08-2004, 02:33 PM
I have rear ported speakers and I needed my speakers to be almost 6 feet high because of a high backed sofa. What I ended up doing was going to the hardware store and buying some L brackets and a couple shelves. I subscribe to the configuration were my rears are facing each other and I have about 2 inches between my ports and wall. I haven't noticed any odd sounds. I do have port plugs but haven't used them. I set the rear speaker setting to small. If you subscribe to the rear speakers facing the listening area, the tilt should give your speakers plenty of room to breathe. You have to hide the speaker wire? If you figure that one out let me know. Maybe we can plant a climbing vine next to them.