FOA Uncle Eric, room problems with two Rel Storms

Phil Hinton

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Eric, and anyone else.

I have recently just got my hands on a second Rel Storm, but setting up has brought some problems to bear. I can't get them to sound correctly with huge missing octaves when performing low freq. sweeps.

I put this down to the room, and I am looking for suggestions on what i can do. I have not yet finished the cinema room, having ran out of cash, so i can change things around a little.

I have added a photo taken from the height of the Barco towards the front to give you an idea of position. I am also Using Boston 555THX speakers accross the front, with a 80hz cut off.

Any ideas?
 
Here is a plan (not to scale) of the room layout.

It is 13.5ft x 14ft and ceiling height is 10ft
 
Hi Phil,
The positioning of your front speakers and subs are very similar to mine. However, as my subs fire foward into the room, the close proximity of the wall behind effects them less than your downward firing subs.

My guess is that in these positions, the Storms would sound 'Bloated'.

Your problem is two fold. Firstly although your room shape is not exactly square, from your measurements (14ftx13.5ft) its not far off square either.
Square rooms are regarded as just about the worst shape for a HT room. I think I've gone into depth on this subject before so I wont bore you with why but instead try and find a solution.

The usual trick with a square room (apart from building one side in to make it nearer the correct shape), is to move everything (speakers and subs) over to one side or the other.
Even as little as 6 to 8 inches makes a hell of a difference.
Of course as your Barco and screen are now pretty much imovable, this solution is out of the question.

This is what to do. Divide the room lengthways into thirds. This would be three lots of around 4.6 Feet.
Then divide room width by 7th's. This would be just under 2 ft.
From the top or bottom centre of the subs (driver centres), place the subs on any of the two 'Third' Lines (I prefer the front third), that correspond to the first 7th line on the left width and the last 7th line on the right width.
Once this is done, one sub should be on the left wall side of the room, as you look at the screen, just under 2 ft from the wall(measured from the centre of the driver dont forget) and 4.6 feet from the front or back wall, and the other sub should be the mirror image of this on the right side wall.
As your room has odd shapes here and there, experiment a little while the subs are in these positions by moving them out a half inch at a time towards the room centre in order to acheive the right balance and weight.

One last thing and its very simple too. Go to your local DIY store and get yourself some polystyrene coving. This is sort of triangular in shape when you look at the ends. Try and find a thickish one at least around 4 inches.
Paint these first to match your decor and place them upright right into the four corners of your room from top to bottom. I use that Liquid Nail stuff (By Unibond I think).
This is a cheap way of making bass traps and will help reduce your problems no end I'm sure.

Hope this helps

Eric
 
Eric,

One last thing and its very simple too. Go to your local DIY store and get yourself some polystyrene coving. This is sort of triangular in shape when you look at the ends. Try and find a thickish one at least around 4 inches.

Excellent idea!! I guess most of us with (dedicated) rooms could use this to improve sonic performance.

Thanks!

Steve
 
Ok, I sat till 5am this morning playing around with the two subs and ghave come to this conclusion.

When using two they are cancelling each other out. This is very rare but can be the only explanation. Usig just one and it sounds brilliant deep and detailed. Use two and there are huge gaps in the response and more boomy.

I have read every peice of advice on the net and tried everything i can think off and no luck.

The room is obviously the pulprit.

So I have decided to get rid of one of the subs, either sell it or trade it for a scaler/doubler or pioneer 737. I have posted the thread in the classified forum.
 
And a big thank you to Uncle Eric for his superb advice.:blush: :D
 
Phil,

Do the subs have a "phase" dial or switch?

Try setting these to different/opposite positions if they do.
 
I played around again tonight,this is a post before I go to bed.

I finally got them singing together perfectly, and boy do I notice the difference.
I sat and read the Instructions for my new 3801 amp, and it appeared that as well as a sub vol, there was also a lfe volume, completely seperate from each other, you can also adjust the front channels seperately, something you cant do with Yamahas which I have owned since getting into HC. So I reset everything for reference volume, and then went about tuning the subs as Eric suggested.
They are close (12") to each other either side of the centre speaker and again 12" from the Screen wall. I spent 6 hrs with bassy excepts on a-b repeat, finly tuning the bass on each seperately until they were nearing excessive, then turned them down using the Amp -db setting, then switched both on and turned the Amp Vol down by -2db. Got out the SPl and checked ref vol, and they came up almost -8db behind the fronts, which is as near Ref level as i can get, and they rock big style, no boom, just lovely deep tight bass that makes your fillings rattle!

Thanks again everyone, and the For sale sign is now down.
P.s. Paul, I have both on Reverse Phase now.
 

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