A7 internal volumn

[mrbill]

I have A7 cabs that I want to use for my home theatre. Problem is with the horn on top it is too tall and covers too much of the screen. I am looking for a way to handle this problem. Would it work to cut the box down some? If so how much could I get away with and not reduce the internal volumn too much. Are there other ways to do this? The L & R speakers are no problem, just the center. Thanks for any help.
Bill

[just me now]

maybe mount the horn inside the cabinet (with the cabinet upside down), in the bass reflex area, with one of the wood slats taken out....

[mrbill]

That was my first consideration, however the horns I have are 8058s which due to size are not conducive to inside mounting.

[GM]

Greets!

It will depend on which model driver is loaded, but probably best to
cConvert them to superior performing 816 style cabs (the early version with the vents across the bottom), set the front channels to 'small' and let the sub system handle the extra load if it can. Otherwise you'll need to upgrade it to handle the extra ~5.77 dB of dynamic headroom required.

GM

[ngccglp]

Another suggestion is to put the A7 on its side, if you have the lateral width in your room.

[mrbill]

GM, I should have been more specific. I have the early version with the vents across the bottom. 515C driver.

"Another suggestion is to put the A7 on its side, if you have the lateral width in your room."

I have the witdth to put it on its side but was concerned that having the center on its side and the others upright would not sound right. How would this affect it?

[GM]

Greets!

The loading will be somewhat different, so will the tonal balance, but probably the biggest difference will be with a horn at ~face height Vs two firing down at you. If you sit far enough away, even this probably won't matter since your hearing is predominantly visual specific when watching a movie.

Hmm, the early cabs had dual vertical vents, the later series had a mid-low horizontal vent, with the last version having a low horizontal vent. Anyway, I was referring to something along the line of the 816A: http://www.lansingheritage.org/image...pro/page10.jpg

For the 515C, a ~3.27 ft^3 net rear chamber volume (Vb) looks good in a sim. For an 80 Hz XO point, somewhere around 66.5"^2 assuming a 3/4" baffle thickness.

Anyway, all that said, why not just DIY an acoustically transparent screen and space them up so that the HF horns are at 2/3 screen height like in a cinema?

GM

[mrbill]

I appreciate all the helpful answers and have gained some new ideas from them.
My question is simply can I cut the cabinet down to make it shorter and then put in a new port, or will this decrease the internal volumn too much or adversly affect it in some other way.

[GM]

Greets!

Simply put, no.

GM

[mrbill]

Thanks GM, I will take that as the definative answer and proceed in a different direction. I'm sorry I misunderstood your previous reply about the cabinet. Mine is the 828 with 515C driver. Ignorance is no excuse but Im stuck with mine so please forgive me for not giving all the information you needed up front.
Bill