[machine]

I'm setting up my office for 2 channel listening.  I may a t some point sneak a center and surrounds in there, but for now I'm just worried about 2 channel performance.

I've read all the posts on here and googled around and am at the point I need some input.

I plan on putting corner bass traps in all corners and to treat for at least 1st reflections.

Room is 12'w x 17'l x 9' h.  Speakers are on one short end, the other short end has two windows which will be coverd by heavy drapes.

Facing the speakers, the right wall is solid, while the left has a door opening starting ~16" back from front wall.  This may force the corner trap in that corner to being different from the standards 45% across corner.. If this is the case, it would be duplicated in other front corner to keep it symetrical.

Now to the questions...

(NOTE: the 3lb 3" fiberglass is in stock, the mineral wool is a 6-8 week wait)

*A*Which would be the best for corner traps (floor to ceiling using 2'x4'):
These wll be covered in burlap
1) 3lb 3" unfaced fiberglass doubled to 6" thickness ($1.50 sq')
2) 6lb 2" unfaced Roxul mineral wool doubled to 4" ($0.50 sq')
3) same as 2, but 3" doubled to 6" ($0.80 sq')
4) 8lb 2" unfaced Roxul mineral wool doubled to 4" ($0.60 sq')
5) same as 4, but 3" doubled to 6" ($0.90)

*B*Cutting the insulation into triangles and stacking in corner to fully fill it seems to be better than just straddling the corner leaving the space behind empty.  I think the stacking them would be easier so I want to do it this way.  How much better is this method and is it worth it?

*C*Would the 3lb 3" fiberglass be ok to use for the 1st reflection point or should I go with someting else in 2".

Thanks in advance for your help

[Ethan Winer]

> Which would be the best <

Thickness matters more than density, and six inches of any of those materals will be great.

--Ethan

[richlo]

> Which would be the best <

Thickness matters more than density, and six inches of any of those materals will be great.

--Ethan

Ethan

for a two channel only setup - its it appropriate to have bass absorbers where the possibility that you may be only dealing with Mid-High Frequencies..I guess it will be dependent on the speakers if they go low

[machine]

Thanks for the info Ethan - would you fill in the corner with triangles or just go across it?  Also, does the 6lb or 8lb get me better performance?

As far as bass goes, I'm going to have a dual GR-Research 12" subs with passive radiators driven by the reccomended modified plate amp which should go down flat close to 20hz.  I'll run the speakers full range and from the second pre-out, i'll fill in from the bottom.  Trying to keep the signal path as pure as possible.

Going to be running the GR-Research 'un-named' Open Baffles, once I get them built.  Have a lot of projects going on....

[bpape]

Even with 2 channel you'll be dealing with the bottom.  

If you're going to go solid, use the 3lb material.  You'll have plenty of thickness.

Bryan

[Ethan Winer]

Rich,

> for a two channel only setup - its it appropriate to have bass absorbers where the possibility that you may be only dealing with Mid-High Frequencies. <

Yes, all rooms need as much bass trapping as possible. While you could definitely have too much absorption at mid and high frequencis, it's not possible to have too much bass trapping. The more you add, the flatter and tighter the low end becomes. Most people will stop adding bass traps - cost, appearance - long before the room is perfectly flat.

> I guess it will be dependent on the speakers if they go low <

Not necessarily. The main bass problems in most rooms are from about 80 Hz up to 300 Hz.

--Ethan

[richlo]

Rich,

> for a two channel only setup - its it appropriate to have bass absorbers where the possibility that you may be only dealing with Mid-High Frequencies. <

Yes, all rooms need as much bass trapping as possible. While you could definitely have too much absorption at mid and high frequencis, it's not possible to have too much bass trapping. The more you add, the flatter and tighter the low end becomes. Most people will stop adding bass traps - cost, appearance - long before the room is perfec ...

Thanks Ethan, BPape for all the free teachings you guys provide continually