Somebody stop me -

[clmrt]

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

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

PT2C-8 Ribbons ( http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=275-085&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. :yes:

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]

MAX SPL.............

[Zilch]

http://audioheritage.org/vbulletin/showthread.php?t=12791

http://audioheritage.org/vbulletin/showthread.php?t=5878

Jackgiff's got a pair of 1.5x upsized Baronets he built, a small EV corner horn originally licensed from Klipsch, that would be worth a try, too.

I'll send him a PM.... :thmbsup:

[clmrt]

Landed Doucanoe's 872A cabinets, (Thanks Ron!) parts should arrive tomorrow.

I think I'll tune for 40hz, so I can mess with plugging one for a change in tuning -

[doucanoe]

Looks like you are on your way!

Let me know when you are up and running so I can listen to them. I still have that other pair. Not sure what to do with them yet.

Hey, do you still have one of those small sealed sub cab for the SVS?

RC

[clmrt]

It's good to see the baffles screw out, should make the retrofit simple enough.

Parts arrived from PE, the ribbons are a little taller than I expected, but they should fit fine. I've been in camping mode for a while, getting things lined up for a trip up nort'.

I wound up giving those sealed cabs away for $5 / 3 at a garage sale. I should have kept one, but wifey said no.....

I do have the big cab I built, ifin ya wanna take it!

(Thanks for the mag, arrived today!)

[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.... :thmbsup:

[Thom]

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

[Zilch]

My understanding is 123A is D123 with a paper dome and Aquaplas.

Don't quote me on that; it's just what I read in the history files here regarding development of L88 and 4310.

[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?

[clmrt]

Well, the jury is still out on that. I fell asleep to Sgt. Pepper last night, which is a good sign - I liked it enough to stay put long enough to actually pass out. :applaud:


They're not bright, that's for sure. Both the woofs and tweets are highly directional so that sitting on the floor brings in more treble. I have the tone controls doing the smiley-face and it fleshes out the music pretty well.

I have some time this morning to let them run in for a while.

And about the bass tuning - I just ran the 1/3 octave warbles and...nice and strong down to 40. All I have is a rat-shack meter, but referencing 80db at 1K, the bass runs pretty clean from 100hz down. No buzzes to chase down!

[00Robin]

They are beauties. And you built them? Are you going to cover the front with that old upholstery or is that passe now? I ask because personally I LIKE the old ugly upholstery with the metallic threads running through the fabric,but I notice everyone's photos show all the works.

[clmrt]

The cabs are resurrected Altec 872A's that LH member Doucanoe had in his basement. I just cut the baffles.

There IS a guy in town who sells the guitar-cab tweed...

[doucanoe]

Boy, those cabs sure cleaned up well. I would imagine that a medium stain would be nice on those but I'm going to put in another vote for oil. That walnut veneer should really pop regardless.

They really fit the room nicely also without being overwhelming. I'm looking forward to hearing your work!

RC

[clmrt]

Two coats of tung, a rub-down with #0000 and a coat of lemon oil to kill the smell...:barf:

[00Robin]

LOVE the wood. Everywhere,the more the better for everything. resonance,beauty,colour....I hope you do get the fabric. I saw it available in antique new old stock,but I can't seem to remember where. It was for wooden speaker cabinets too. Maybe it'll hit me and the light will turn on.
Very,very nice.

[jackgiff]

They finished very, very nice. Congratulations on an excellent job.

For what it is worth, Antique Electronic Supply in Tempe Arizona has a nice selection of antique grill cloth. Their web site is <http://tubesandmore.com/>

I have used them on many occasions for grille cloth, and love what they sell. A small sample package of everything they sell in grille cloth is available, and much better than trying to decide by looking at pictures.

[00Robin]

Hey Jack,thank you for the link. I think I'll be frequenting that place a few times for sure. I didn't notice Hammond on the list but I can't have everything I guess. Thanks again,Robin