[warnerwh]

I have a friend with a room 14'-4" x 17'-5".  There's an alcove in the left front corner that is 4'-11" wide by 1'-8" deep, making the front wall 16' wide.  I have a diagram in a pdf  file so if anyone can help me upload it I'd appreciate it.

There's 8 of the 2x4x4" GIK traps in the room. One in each corner, one behind each speaker and one on each side wall at the reflection points. They are not mounted, just leaned up against the wall for now. Floor is carpet and pad over concrete. There's also have eighth nerve corner treatments in all the corners.

There's a 65" RPTV in between the speakers which I'm sure does not help. The back of the speakers are out 30" from the back wall and about a foot in front of the TV. They are 26" from the side walls and 7' apart. Seating position is 10'.

For whatever reason imaging and depth is suffering. Equipment is: Butler TDB5150 amp, Modwright pre, Ack dack feeding Music Hall CD player through Vmps RM 30 speakers. Bass could be better too. Any help is greatly appreciated. Thanks

[samplesj]

So its not toe in related?

What is the ceiling material?  Is there a ceiling first reflection point trap?  Is it a plush carpet or more like a commercial thin berber and pad?

I'm assuming that the 4' height is good enough to cover his ears, but maybe they could be sat on top of something to raise their height about 2' or so off the ground.

Are the GIK traps faced or not?  Rigid fiberglass facing is fairly reflective to mids/highs (I think) so it may not really help any more than just the wall.

BTW when you say 26" from the side walls you mean 26" from the normal corner and 26" + 1' 8" on the other right?

[mca]

No, I have tried all degrees of toe in
 
Ceiling is drywall, carpet is plush with heavy pad
 
The height of the panels is above my ears, but I could try raising them

I don't really know, can't find that info on their website

26" from the back outside corner, closest part to the wall

[samplesj]

I hadn't really tried to measure out everything before, but now that I am, I can't get the dimensions to sync up.  The front width given is either 14'4" and 16', but if the speakers are 26" from the side wall and 7' apart then we've only got 11' foot there.

Can you experiment with a ceiling panel to help kill that first reflection?

I'd try to get the panels mounted with a good spacing from the wall or straddling corners before trying to measure the bass since that will affect how much they absorb.

I can't really help too much, but I didn't want it to sit without any responses.  Maybe we'll get one of the experts to chime in with some help if this stays near the top.

[Bob Wilcox]

I also think you should damp the 1st reflection on the ceiling. As I added materials in my room, the ceiling became more of an issue. Using RM30s, you may have a fairly wide 1st reflection point across the ceiling.

You may also wish to put materials on the wall surfaces surrounding the the TV and consider mounting 2 of your panels on stands so you can move them in front of the TV when you are not watching it.

Bob

[mca]

I hadn't really tried to measure out everything before, but now that I am, I can't get the dimensions to sync up. The front width given is either 14'4" and 16', but if the speakers are 26" from the side wall and 7' apart then we've only got 11' foot there.

My HT sub and equipment rack sit in the alcove. The left speaker has a further distance to the side wall because of the alcove.

I was thinking of mounting a couple of the 2" thick traps to the sides of the TV. I may also try throwing a large, heavy blanket over the TV when listening to music.

[John Casler]

Hi Warner,

Happy New Year (a few hours early)

I assume this lack of depth and such is during 2 channel?

If so, I would try the following:

1) Throw a large Comforter over the TV to see what those reflections are doing.

2) Change convergence angle to more "on axis"

3) Elevate the RM30s 6-8"

4) If possible move listening position closer to 7'-8'

For bass, try pointing the woofs in and out to see which loads the room the best.

Good Luck!

[warnerwh]

Happy New Year to you too John!  Best wishes to you and your family!

 Those are good ideas. I read up on the Butler amp last night and learned it has a tubed output stage.  This may be an issue. Mike will try a SS power amp and see if that helps.  This same issue has come up before and has been cured with a powerful SS power amp.  One possibility too may be to run an ss amp like a Parasound with pots(to match levels) on it to the bass and the Butler to the top.  

 This just occured to me. Something else that could be a problem is some of the output from the sub may be cancelling out the bass output of the mains. Don't know if phase between the sub and mains has been dealt with or not.  Good bass helps imaging too.

[mca]

2) Change convergence angle to more "on axis"

Not sure what you mean, can you explain further?

3) Elevate the RM30s 6-8"

I think I have some bricks I can stack and prop the speakers on to try this out

4) If possible move listening position closer to 7'-8'

Should I move the speakers out or my listening position in to get this distance?

output from the sub may be cancelling out the bass output of the mains

Sub is not used in 2ch, only movies

Thanks for the suggestions and happy New Year to all

[John Casler]

2) Change convergence angle to more "on axis"

Not sure what you mean, can you explain further?

4) If possible move listening position closer to 7'-8'

Should I move the speakers out or my listening position in to get this distance?

Usually VMPS speakers are "toed in" (converged) to crossfire 1-2 feet in front of your face.

Sometimes at listening distances greater than 7 feet, it may be nessessary to gradually move that convergence point to be more "on axis" (or have the speakers firing more at your ears than in front of you)

This will require experimentation.

Moving the speakers "out" might also deepen the soundstage, at the expense (many times) of deep bass.

If you have a sub(s) then by all means move them further out as long as the sub still blends.

Make sure and not "overlap" sub frequencies with the bottom of the RM30 woofers too much, as those frequencies will get fuzzy and muddy.  This is especially true if you have the subs in a different firing plane than the woofers and no adjustment (phase dial) is available.