A victrola case, a bookshelf, and a pair of Alpair 7p's

I want to make something that sounds reasonably musical, in a space that's not ideal, using mostly parts on hand. So I'm looking for ideas and suggestions that give a good return for the effort in the available space.

On one side of the TV is an old Victrola case with all the audio parts missing. I've refinished it, mounted my Dual 1009 turntable in the top, and hid a Crestron CNAMPX16x60 ($48 from Goodwill because it was dented and needed easy repairs!) amplifier underneath. I'd like to put a speaker where the original speaker was, which is 16" W x 12" H x 18" D. On the other side of the TV is bookshelves. The space is 20" W, flexible height, and 12" deep.

Yes, it's a HT system, but I care most about sound with instrumental music. I have a sub-woofer, so I'm less worried than I might be about the low frequencies. I still like the sound of my 30 year old Advent Legacys, but there's no room in the front so I'm moving them to the back to replace some cheap Sony bookshelf speakers. I could cannibalize those, not sure it would improve anything. I have a pair of Alpair A7p that I'm thinking would work well for this. :idea:

I've looked around at some of the speaker cabinet designs on line. The CGR Mar-Ken drawings with the driver mounted on different faces got me wondering if it would work well to make a pair of nearly identical enclosures with the driver mounted on the smallest face for one and the largest face on the other. Would I be likely to hear the difference? Similar thoughts on folded pensils, or folded Voigt pipes, or...? Are there designs that would do better with little space around them, and right and left being rearranged versions of that design? Things you could do to compensate for the differences between the sides?

Nearly all the designs I've seen look like things I'd be capable of building. My general electronics/woodworking shop and skills are up to it. Miters, mortises, dovetails, no problem:D. But I've never built speakers before.
 
I'll assume you're intent on integrating the four-inch Alpairs into the existing old Victrola case..do you want stereo or mono? For stereo, a side firing arrangement seems most logical...but of course imaging, beaming & a whole host of things go out the window. Dividing up the limited internal space into two left & right sections is likely "too tight", & system Q is going to be too high & way off 0.707...
Some pictures of your old Victrola would be nice, & maybe some sketches?


-------------------------------------------------------------------Rick.........
 
The CGR Mar-Ken drawings with the driver mounted on different faces got me wondering if it would work well to make a pair of nearly identical enclosures with the driver mounted on the smallest face for one and the largest face on the other.

Sure that would work, but — in open space — they will start to have baffle step at a different frequency. This is greatly affected by the room and what you have beside the speakers (given skinny i assume there is a space it needs to fit into?)

dave
 
Some pictures of your old Victrola would be nice, & maybe some sketches?


-------------------------------------------------------------------Rick.........

Right, I see a few important details didn't make it from my head into my post :blush:. This attached picture shows the spaces I have in mind.
 

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There is so much stuff around where the speakers are that any differences in performance based on the baffle width will be overwhelmed by the influence of all that stuff.

Go for it.

dave

Thanks, Dave. It's good to know the relative influence of things, and not put excessive effort into optimizing the smaller influences. Simplifying assumptions and all that. Open space it is definitely not. My wife is a librarian, and this is sharing a room with lots of book shelves, and even a large card catalog (full of small things other than cards).
I'm thinking skinny end out for the victrola case just because depth is the largest dimension I have to work with there. Also, I was thinking of leaving any space not taken up by the speaker case as storage. That would work better with the speaker on one side. I would want a panel or door over that space, flush with the speaker front baffle, I think.
In the interest of symmetrical baffle steps, I should be able to position the drivers the same distance from the inside edges of the victrola case and bookshelf.