Corner Boom

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ARCVT100

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Hi all, any ideas on how to eliminate or get under control the booming bass I ma getting with my Acsents? I have to put the left speaker in a corner (yep I know!). There are no other options really available for my room unfortunately.
 

risabet

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Good Luck!

It is nearly impossible, in my experience, to tame the boom that happens when you place a speaker designed to operate in freespace in a corner. The corner placement causes a boost in the bass of around 9db, I think, the frequency determined by the distance of the woofer to the three boundaries. Furthermore, corner placement will excite all of the room modes maximally, giving the one note boomy bass you are getting.

You might try rolling off the offending speaker's bass but then you have no bass at all. Can't you rearrange the room, the Ascents deserve better. :(
 
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Dan Osib

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Your best bet is to purchase a digital room correction preamplifier like the Tact RCS 2.0S to eliminate the bass boom. It will also give you a sound that is overall better than any analogue preamp available, even the Conrad Johnson ACT 2. It sounds crazy I know, but this is actually what I have heard with my own ears. Oh yes it's inexpensive as well.
 
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attyonline

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Sorry if this advice seems cold, but the Ascent is a great speaker that deserves good associated equipment and correct placement. If you have to place one in a corner you will never get good sound from it. I suggest you sell or trade it for some small booksheves that will not go much below 80 hz. Crummy deal but I suspect you will not be happy unless you can get different speakers or better placement options with the Ascents. :(
 

DavidG

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Traps!

Of course, you could try some room treatments, especially some bass traps located in the corners behinds your speakers.

This isn't a guaranteed fix, but it's got a reasonable chance of working.

Cheers,

David
 

roberto

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move from the corner when listening...

Hola. Why don't you move the Ascent from the corner, at least 3 feet forward when you are listening, and when you are not, put them back at the corner?...just another thought. All ML needs at least one meter from the back wall, this set up will kill the stand waves, will give you clean bass, and the best 3-D sound...then when you are not listening, put them back in the corner with no problem...hope this can help!
Happy listening and trust your ears!
Roberto.
 
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Kevin

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There are no bass ports on the ascent speaker so the woofer is forward firing, so placing it in a corner will not affect the bass. It is something else.
 

attyonline

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Kevin said:
There are no bass ports on the ascent speaker so the woofer is forward firing, so placing it in a corner will not affect the bass. It is something else.
I think it will affect the bass. The bass waves are sufficeiently long that they will interact with the corner regardless of whether the speaker has a rear port or not, especially when the speaker is in the corner :rolleyes:
 

Muad'Dib

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Room modes are a pain in the ass to fix without re-building/furnishing the entire room. Find where the standing waves are the worst and move a piece of furniture or acoustic damper there to see if it helps. Move your listening location - it's easier.

Ported or sealed is irrelevant - standing waves do not orriginate only from the back wall.

-D
 
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ARCVT100

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Thanks for the feedback all! What about Bi-amping with an Integrated AMP? One advantage i see immediately is using the balance control to phase out the left channel.
Bass is not a real need (though I do like the bass i do get from the ML's as a supplement,since I have two subs in the system anyway.(located on the listening side), and yes i have turned them to zero to see where the offending bass standing wave is coming from.
Are there any special considerations for the Ascents other than removing the jumpers between hi and lo?

FYI I am running Tranparent plus cables with an ARC VT100 MKIII and ARC LS15 PREAMP. 2 VELO subs HG10 SX.
 
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Kevin

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Tranparent plus cables
There is one problem, running that crap could affect something due to the poor construction. Go buy a set of cables from www.bluejeanscable.com or make a DIY.


I think it will affect the bass. The bass waves are sufficeiently long that they will interact with the corner regardless of whether the speaker has a rear port or not, especially when the speaker is in the corner
So you think that a forward firing woofer will send a sound wave across the room, bounce off every and anything in its path and hit the proper angle for a direct return path to the corner?
 
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Bonedust

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Kevin said:
There are no bass ports on the ascent speaker so the woofer is forward firing, so placing it in a corner will not affect the bass. It is something else.
its not something else....the position of the speaker in relation to the side wall definitly changes the bass sound.
 

garmtz

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Putting a speaker in the corner wil excite all the modes of the room and is BOUND to result in room boom, ported speaker or not! Because the woofer is SOME distance from the wall can be a bit advantageous, but not much. The best suggestion yet is to try the TacT RCS 2.0. No other way around a crammy set-up I'm afraid, apart from using speakers that do not excite the room modes as much (a very small speaker).

EDIT: I am HAA certified, so I know room acoustics.
 
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Barbados

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Your transparent cables are fine.

When a speaker is loaded in a corner, regardless of which direction it is firing in, each adjacent wall can produce room gain of approx 3 db (most noticeable in bass frequencies). The overall gain when you add it up will be more than enough to wreck your bass. The greater the acoustic power of the speaker the greater the excitation of the room nodes hence why people are recommending you switch to bass shy bookshelfs if you really are going to leave the Acent in the corner.

A digital equalizer cannot correct bass BOOM only peaks/dips. Reducing the level of output at certain frequencies at which you have boom will indeed reduce the level of the boom but will still leave the slow decaying bass intact. This will be clearly evident on string bass where certain notes will sound blurred (try Holly Cole - Don't Smoke in Bed or Temptations). I would suggest you really try rearranging the room or moving the speakers out from the wall on a platform as Roberto suggested.

Advice seekers beware of this Kevin person.
 
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risabet

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Kevin said:
There are no bass ports on the ascent speaker so the woofer is forward firing, so placing it in a corner will not affect the bass. It is something else.
Wrong! It couldn't matter less whether or not the speaker is ported. The size of bass waves renders the cabinet functionally transparent, actually the bass waves wrap around the cabinet rather effortlessly. The proximity of the woofer to a surface adds a bass boost of 3db per surface, a corner gives a 9db boost regardless of the type of woofer used.
 
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Kevin

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Advice seekers beware of this Kevin person.
That's right because I am right while most of you are wrong.

If your walls are really adding that much boom to your bass go out and buy some cheap sheets of cork from a home depot. For temporary use just to see if anything changes.

The proximity of the woofer to a surface adds a bass boost of 3db per surface, a corner gives a 9db boost regardless of the type of woofer used.
Depends on the wall. I can not see dry wall adding that much, maybe if your walls were thick dense cement.
 

risabet

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The Fact

Kevin, don't take my word for it, read the following article by Allison Acoustics, whose founder Roy Allison pioneered the study of room interactions, for a detailed description of the physics behind the bass reinforcement.

<a href=www.allisonacoustics.com/one_system.html>Allison Acoustics</a>
 

garmtz

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Kevin said:
That's right because I am right while most of you are wrong.
Right.... :rolleyes:

If your walls are really adding that much boom to your bass go out and buy some cheap sheets of cork from a home depot. For temporary use just to see if anything changes.

Depends on the wall. I can not see dry wall adding that much, maybe if your walls were thick dense cement.
The cork will do NOTHING to the sound... It will not change the weight of the walls in any significant way (weight would help to reduce the resonant frequency and damping of the walls) nor would it change the dimensions of the room (which would have an effect on the room modes). Bass is totally undisturbed by any objects or wall treatment that are/is small/thin. You of all people should know that voodoo tricks like cork on the wall would do zip to change the bass... :p

Kevin, please study room acoustics before making statements as if they were true, it destroys the believeability of both yourself and this forum.
 
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