Somebody stop me -

[clmrt]

Before I make a mistake. Actually, I'll just do this, so don't bother.

D123 in 3.3 cubic feet tuned to 30hz, .33mH inductor for low-pass.

PT2C-8 Ribbons ( http://www.partsexpress.com/pe/pshow...75-085&scqty=2)

4.8uf for hi pass.

XO is estimated at 4500.

I might buy a few extra caps and inductors and mess with the XO outside the box, and I'll be able to passively bi-amp with a T-amp and a tube amp. Sounds like a good way to piss away a few weeks...

[Zilch]

BB6P likes 40 Hz better, though 30 Hz is more "banana-oid."

They both end up about the same place at -10 dB.

30 Hz has significantly less LF power handling capacity (bottom).

[Well, maybe. I'm not sure how to interpret that, actually.... :dont-know ]

[doucanoe]

I for one thinks it's a smashing idea. But then again, I have an alterior motive.

I not sure about the particulars, but I think that move might just gain me 6.6 cu-ft plus in my basement

RC

[clmrt]

G -

I'll buy the goods for 2K / 12db and 3K 6db as well. I had some 414's XO'd at 3K in the 847A, seemed to work fine, been a few years...

I don't know why I settled on 4.5.

I might buy a few caps for 8K hipass too, and let the wooger run free.

I think (think) the D123 specs out close to 94db, same as that tweet, and in any case, both of my amps have volume pots. I should be OK there.

*scratches head*

I ran the box sim in Win ISD and power handling was around 15w all the way down. Might have to revisit. Max SPL never went below 101, so that gives me about 10db headroom as I never listen louder than 90 or so.

[clmrt]

Tuning, 45, 40, 35

[clmrt]

Power...

All conjecture. I should have something to report on by Monday, although it'll just be full range impressions until XO parts arrive.

[clmrt]

Proposed baffle layout....

The ribbon tweet was bigger than I expected, and can't do vertical alignment.

Should I be concerned with XO frequency vs driver spacing?

Is there a best position for the ports? I'd prefer to keep them on the front so I can snug the cabs up to the back wall if necessary.

*not to scale....

[Thom]

I've seen D123 frames that have been cut so they look like 123A frames and will front mount. Have no idea pros and cons.

[clmrt]

That ties into my other little problem to overcome - I bought carriage bolts to insert through the face, and lock washers and a pair of nuts to secure it all. But the nut goes below the frame "vanes" and I cannot secure them with any tool.

So I'll try to find a spacer or just a stack of flat washers to elevate the nuts above thr frame...eep.

[Zilch]

Aluminum tubing from the hardware store. Part off spacers of any desired length....

[Thom]

With the paper off is the 123a the same speaker, other than the visually obvious? Can a 123a be made a D123?

[clmrt]

And there we go. I finally got off my ass and did something. They sounded wonky when I first hooked them up. I forgot to change the taps on the amp, so I moved them from 4 to 8, and while I was at it, I decided to pull the inductors from the XO. Now the D's run full range, I like it. Ribbons still come in around 4500hz.

Next - Grilles.

[clmrt]

And stain - gotta stain them...

[hjames]

They look very nice - the wood looks like it has some character - maybe just oil them down?

[Zilch]

And.... ???

How do they sound?

Who all's out there nearby?

Briang, Doucanoe, Redboy, more?