D140F cabinet build

rpsands · #1 07-30-2010, 12:12 AM

Hey,

I need some quick advice on the design of a cabinet for a JBL D140F I picked up out of my dad's storage crap. He had it in an old PA cab and I grabbed it when he was getting rid of stuff.

Figured I'd make him a nice little cabinet for his old silvertone tube amp. Trouble is, I can't find any designs or measurements for the Showman cab it's supposedly quite good in. I can't find any TS specs either.

Anyone have a good box layout for it? Port tuning and box volume should be all I need to get rolling.

It seems to have a pretty bright top end based on some testing in the PA cab, so I am thinking it'll do OK as a guitar cab -- anyone know different? I realize it's marketed as a bass speaker.

gbarchus · #2 07-30-2010, 03:22 AM

I think the perfect cabinet for that speaker is a JBL Cabaret 4625B. I've owned quite a few of them. Still have one with a JBL K145 loaded in it. It's my "go to" 1X15 cabinet.

http://www.audioheritage.org/html/pr...bl/cabaret.htm

You should be able to find some plans for it somewhere on the net.

Here's a pdf file from JBL on Yahoo ("Please click here to check the current page"): http://74.6.146.127/search/cache?ei=...euVzR5Od6hQA-- Sorry, it's the best I could do.

Gale

Bassmec · #3 07-30-2010, 06:31 AM

This might help, I used to have a Pair of JBL K140 MI cabs they sounded great, lots of bright top end as you say, not a reggae
speaker but a totally classic Rock tone:
http://www.audioheritage.org/vbullet...nclosure-Plans

rpsands · #4 07-30-2010, 09:38 AM

Thanks guys!

JimmyM · #5 07-30-2010, 09:48 AM

b-15 double baffle cab. no idea what the specs are, but it's not very complicated. except for the baffles, and they're not even that complicated for a high intelligence dude such as yourself.

rpsands · #6 07-30-2010, 10:43 AM

Got some measurements of one, Jimmy? I don't have the foggiest idea what a double baffle is though

John D · #7 11-07-2010, 02:44 PM

Just stumbled on to this old post and was wondering what the outcome was. Any updates, additional suggestions?

billfitzmaurice · #8 11-07-2010, 02:57 PM

The D140 pre-dates T/S. The specs are probably close to the K140, fs 30, Qes 0.22, Qms 4, Vas 297L, Xmax 5mm, Re 5.5.

JimmyM · #9 11-07-2010, 02:58 PM

btw, there was a whole thread about building double baffle cabs recently with diagrams and measurements.

John D · #10 11-07-2010, 03:06 PM

Quote:

Originally Posted by JimmyM

btw, there was a whole thread about building double baffle cabs recently with diagrams and measurements.

Thanks Bill. Yeah, Jimmy, I saw that and have been thinking about a couple of B15 style cabs or a couple of TL style. They will be paired with an old Showman amp. Which do either of you suggest? I'm not looking for super volume. I just have the old Showman and a couple of D140s laying around and thought I might but them back in service.

tdvt · #11 11-07-2010, 03:15 PM

This will give you outside dimensions. You'll have to work specifics from there.

BLACKFACE SHOWMAN

(There are other versions on the same site)

I also have a not-great scan of a "tone-ring" cabinet sketch from a brochure if you're interested in that.

JimmyM · #12 11-07-2010, 03:15 PM

been decades since i plugged into an old ev cab. i love the double baffle, though. some don't think it goes low enough but it goes low enough for me.

John D · #13 11-07-2010, 03:25 PM

Thanks for the input guys.

lbwdog · #14 11-07-2010, 03:44 PM

RP;
I'm sure you've already made your move on this but I am curious if you were planning a guitar or bass cab?

You're knowledgeable on cab building, but I was wondering if you thought about an open back cab which would be non-critical for guitar. One of my old guitar players always used JBLs for his steel amp which calls for extended bass response, so his cabs were closed back. In fact, he was a Peavey endorser so he used one of their amps designed for steel.

For guitar, I'd try open back at first.

rpsands · #15 11-07-2010, 04:52 PM

I wound up making a 3 cubic foot or so ported box (tuned pretty high, I think around 70hz) with a port plug to seal it if desired, as the first option. My dad is a bass player too and likes pretty bassy guitar tones, so figured he'd like something that had a decent shot at doubling - not really sure. If it doesn't work out, I figure at that size I can fool around with it some - cut the back open or whatever.

Or I could tune the port lower and put a 3015 in there and he'd have a nice bass cab.

Probably not ideal, but the idea was more to be flexible than perfect, since I couldn't find anything really concrete at the time.

The cab's all built and mostly done, just need to do some finishing work and put the driver in.

John D · #16 11-07-2010, 06:16 PM

Quote:

Originally Posted by rpsands

I wound up making a 3 cubic foot or so ported box (tuned pretty high, I think around 70hz) with a port plug to seal it if desired, as the first option. My dad is a bass player too and likes pretty bassy guitar tones, so figured he'd like something that had a decent shot at doubling - not really sure. If it doesn't work out, I figure at that size I can fool around with it some - cut the back open or whatever.

Or I could tune the port lower and put a 3015 in there and he'd have a nice bass cab.

Probably not ideal, but the idea was more to be flexible than perfect, since I couldn't find anything really concrete at the time.

The cab's all built and mostly done, just need to do some finishing work and put the driver in.

Let us know how it turns out.

D.M.N. · #17 11-07-2010, 08:16 PM

Wait, you have a couple D140s? Build yourself a Sunn cab and live happily ever after. Either the 2000s or 200s model cab.

mark107 · #18 11-07-2010, 10:20 PM

Quote:

Originally Posted by D.M.N.

Wait, you have a couple D140s? Build yourself a Sunn cab and live happily ever after. Either the 2000s or 200s model cab.

I had lots of these in Sunn cabinets back in the day, and they made me very happy. Though I am not sure they would make me happy today. BTW, I also had them in a Dual Showman cabinet, and that was NOT good. The cabinet was rather shallow, and the back would rattle something fierce if I turned it up. NOT recommended!

BTW, speaker DO get old, and I personally would not waste my time on 30-40 year old speakers. The surrounds dry out, and who knows what else. I inherited a pair of old (and VERY expensive) JBL hi-fi speakers from my parents, which were fantastic sounding speakers in their day, but they now sound weak and wimpy now, They have effectively "died".

JimmyM · #19 11-07-2010, 10:34 PM

they can be fixed. sure, it's not cheap, but it beats getting rid of classic speakers. also, there are some folks who actually took care of their speakers and didn't let them rot, and they're doing quite nicely. i just happen to have a set of old cts's in my 73 super reverb that came with it and were never reconed and i wouldn't trade them for the world.

johnk_10 · #20 11-07-2010, 11:45 PM

if it's a single 15 cab, i'd build a 1/2 size Sunn 200S cab. IMO, the showman is an awesome cab for a D(or K)140, but you'll need a double baffle/tone ring and braced back to build it right and they ain't cheap. they are also pretty heavy cabs.