[Marc B]

I need a bit of help regarding bass issues.

My room is about 15x11x8ft in size. Speakers are Dali Helicon 400s and I have 4x244s and 6x242s panels in the room at various points.

My problem is a large bass suckout. If I have the speakers placed across the short wall, I have a huge dip around 70hz and another at around 140hz.  If I place the speakers across the long wall I have a large dip right on the kick drum attack of 90-120hz.

As you can imagine this is robbing the music of dynamics and making it a bit flat. I either lose the musics impact or the underlying bass. I can't seem to win.

Pushing the speakers closer to the wall lessens the dip but swamps the midrange.

Changing the speakers to smaller standmounts won't do much apart from effectively HPF the lower registers.

Any thoughts ?

[MaxCast]

What do you have in the corners?
I would suggest the tri traps or 6" bass traps in the corners floor to ceiling.  If you can diy I would cut 2'x2' 703 into triangles floor to ceiling.

Also, have you tried moving you centerline to the left/right 6-12" or so?

[Marc B]

It's a pretty small room and there's only so many acoustic panels one can put it in without it looking like a padded cell

Good idea on the off centre placement , I usually measure from the side walls and get them spot on the same distance.

Will try that 

[max190]

Marc B,
When you had your spkrs on the shortwall, how far from the front wall where they measuring from the front center?

How far was the LP to the rear wall?

Since you have 10 panels are any of them mounted on the wall directly behind the LP?

[twitch54]

My room is about 15x11x8ft in size. Speakers are Dali Helicon 400s and I have 4x244s and 6x242s panels in the room at various points.
Any thoughts ?

Not sure where your 'various points' are but given your room demensions, corner bass trapping(all four) and first point of refection is where one should start.

[Marc B]

Marc B,
When you had your spkrs on the shortwall, how far from the front wall where they measuring from the front center?

How far was the LP to the rear wall?

Since you have 10 panels are any of them mounted on the wall directly behind the LP?

I had the speakers roughly 3-4ft off the wall behind them and about 2ft from from the side walls. (to front centre cone)
I also had the settee about 2ft from the wall.

I had it more or less at the cardas calculator settings but with a bit more space between the speakers.

I've changed the room around so they are on the long wall and they are 2ft from the rear wall and about 3ft from the sides.

As for traps , due to my room I can't have bass traps in 4 corners as I have a door in one corner.

The layout of the panels are ..

1x244 in each corner behind the speaker.

2x244s at rear of head behind settee

3x242 on each side wall from middle of room to rear wall, starting on first reflection points.

I know it isn't an ideal living room but I need to get the best from it either way. I also like the sound to have a good pin point centre image and tend to set the speakers up for that more than outright balance.

My other thread when I first got the panels ,

http://www.audiocircle.com/index.php?topic=71539.msg668534#msg668534

[max190]

Are you willing to try them again setup on the short wall?

[Marc B]

It depends ,

I found the short wall introduced too much room. I prefered it listening near field with the speakers pulled out to the half way point. Though this made the room unsuitable for normal living.

What do you have in mind ?

[bpape]

The fact that the nulls changed when you turned the room suggests one of two things, or both.

- Seating distance to rear wall (unlikely as you have 244's behind you already)

- Boundary interaction. 

My guess is boundary interaction.  Try taking off the rear most pair of 242's and placing them directly beside or directly behind the 2 front main speakers.  If this helps, try the other position.  If this helps more, then you may be better off using the 242's in those positions rather than for general decay control.

Bryan

[max190]

Sounds like this is not a ded space for just listening to music. Right?

[Nyal Mellor]

Sounds like speaker boundary interference. Try moving some of your bass traps to the reflection point on the front wall (behind the speakers). You'll need at least 6" to have an effect.

[Duke]

Try rotating the speaker-listener-speaker triangle about 25 degrees either clockwise or counter-clockwise as seen from above (and that 25 degrees is a very broad approximation).  The idea is, you want the speakers to be a significantly different distance from all of the room boundaries in the horizontal plane.   In my opinion, asymmetry is your friend when it comes to positioning bass sources within a room.

If that's not feasible and/or doesn't help enough, you might consider adding a subwoofer.  Get one with a steep-slope lowpass filter so you can place it well away from the mains, and just use it to add a little bit more energy in the bass region.  Its room-interaction peaks and dips will be different from those of your main speakers, so it should partially fill in some of those big dips.  You want just enough volume from the sub to improve the quality of the bass (by virtue of having asymmetrically distributed bass sources).  I have never tried this in a situation like yours, but as a general principle asymmetrically distributed bass sources works quite well.