# Help me choose a Boxed In-Wall Surrounds



## hddummy (Mar 9, 2007)

I'm building a dedicated room-in-a-room theater in my basement and I'm working on speaker selection at the moment( build thread ).

I will be building surround speakers into the pilasters around my room to get a completely clean look. They will be fully enclosed sealed speaker boxes on the back side. I'm just looking for some opinions on which of these two designs to go with.

The In-Khan-Neatos are designed specifically for this purpose.
If my thinking is correct, the Zaph 5.3c can be built vertically and also serve well in this case.

Looking forward to your opinions or any other possible suggested designs. Thanks!


----------



## GranteedEV (Aug 8, 2010)

The nice thing about in-wall surrounds is that you don't need any BSC, so sensitivity gets a pleasant boost. On that note though, you can't build just any design without removing the BSC because your average bookshelf type speaker would sound boomy mounted in a wall. The other tough thing is all the diffraction from the wide "baffle", which creates a bit of a harsh treble effect.

I think a pair of these tilted slightly down, without BSC circuits, would be an optimal surround speaker:

http://www.audioheuristics.org/projects_gallery/ER18DXT/ER18DXT.htm

the DXT lens effectively becomes the baffle, so diffraction effects are no longer as frustrating. I would simply seal up the woofer though, no port, if you can get bass down to 80hz.


----------



## hddummy (Mar 9, 2007)

interesting concept...that is the same tweeter I am using on my main speakers. I am building the Idunn Kits. Perhaps I could use those instead. I do like the idea of using the DXT tweeter because of it's unusually consistent off axis response.

However, both of the kits I suggested above are designed with BSC circuits where the speaker is intended to be placed next to large flat surfaces.


----------



## hddummy (Mar 9, 2007)

http://www.seas.no/images/stories/diykits/pdfdataheet/idunn.pdf

I'm far from expert, but I don't see anything in this crossover that looks like a BSC circuit to me. If you look a their free air response graph, there is a small drop in SPL at around 250Hz. Is that because there is no BSC circuit in the xover?

PS...just using this to try and learn me something.
http://www.quarter-wave.com/General/BSC_Sizing.pdf


----------



## GranteedEV (Aug 8, 2010)

hddummy said:


> http://www.seas.no/images/stories/diykits/pdfdataheet/idunn.pdf
> 
> I'm far from expert, but I don't see anything in this crossover that looks like a BSC circuit to me. If you look a their free air response graph, there is a small drop in SPL at around 250Hz. Is that because there is no BSC circuit in the xover?


If I had to guess, they're using a much larger inductor coil to roll off the woofer earlier in order to compensate for the diffraction loss.


----------

