PDA

View Full Version : 4688 TCB Monster Subwoofer



Zilch
08-03-2005, 02:12 PM
Triple Chamber Bandpass sub uses dual 18" drivers in "Push-push" configuration. Motors in center chamber.

Drawing shows center (red) and outer (blue) chamber details separately. Bracing comprising center chamber "port tubes" only shown.

[Oodles more bracing therein. :p ]

Tech note here: http://audioheritage.org/vbulletin/showthread.php?t=6289

JBL Lit here: http://www.jblpro.com/pub/obsolete/4688.pdf

JBLnsince1959
08-03-2005, 02:38 PM
at what power does this achieve "escape velocity" and orbit the earth :p

Zilch
08-03-2005, 02:53 PM
:hmm: Never thought of that.

More down to earth, we're construction contractors.

It's on the capital equpment list here under "Demolition." :D

richard c.
08-03-2005, 02:57 PM
Zilch,

I noticed this awhile back in your photo, and it got me thinking. "I bet I could build one of these IF I had some pictures and the plans for one. And here they are.

I wish I lived closer to you, so I could take a bunch of pictures, and take all measurements. I would love to build one of these monsters. I think it would be perfect for realistic pipe organ "power".

I could build this and install a couple of $29.95 "Super Woofers" that I could find in a surplus catalog somewhere, and I would be in heaven.:D

AND, than I could tell everybody that it was "genuine" JBL.:bs:

No, really I would like one to lay down and use it for a platform under a big screen TV. Talk about LF effects!

Richard C.

JBLnsince1959
08-03-2005, 03:04 PM
Zilch,


No, really I would like one to lay down and use it for a platform under a big screen TV. Talk about LF effects!

Richard C.

or better yet, make one and put cushions on it and sit on it while watching the movies... girls I think would REALLY like that......

richard c.
08-03-2005, 03:05 PM
Zilch,

Do you think this would require a medical release form to be signed by everyone in a normal sized room with this? Might reveal some underlying heart problems.;)

Richard C.

Zilch
08-03-2005, 03:13 PM
Yes.

"Informed Consent" forms are a necessity.... ;)

We need info on the 15" and 12" versions, now, models 4685 and 4682, respectively.

Who's got 'em?

http://www.jblpro.com/pub/obsolete/4685.pdf

http://www.jblpro.com/pub/obsolete/4682.pdf

Consider all of the homeless drivers out there.... :p

pelly3s
08-03-2005, 10:01 PM
Why does someone need that? Oh I know because its really cool

Zilch
08-03-2005, 10:22 PM
Why does someone need that?Surely you KNOW this ain't about "need."

[We're doin' RESEARCH here.... ;) ]

JBLnsince1959
08-04-2005, 05:10 AM
Surely you KNOW this ain't about "need."

[We're doin' RESEARCH here.... ;) ]

:applaud: :bouncy: :thmbsup:

Yes, that's the name of game....

Regis
08-04-2005, 06:56 AM
Gawd, Zilch, I thinketh you've gone over the edge! :p The graph is nearly jaw-dropping if I read it right. 100+ DB at 30hz!!! Car alarms will be going off for blocks around!

JBLnsince1959
08-04-2005, 08:05 AM
If I'm reading this correctly, it looks like it reaches 100 at around 13 to 14Hz and from there it's "all up hill"

Damn Zilch, you better have some protection with those puppies or put them really far away from the listerer. :applaud:

Cyclotronguy
08-04-2005, 09:57 AM
Hey Zilch,

If we're not living on the edge... we're taking up too much room. :D

Cyclotronguy

Zilch
08-04-2005, 11:19 AM
:hmm: What if I put 2242H's in it...? :hmm:

JBLnsince1959
08-04-2005, 11:47 AM
:hmm: What if I put 2242H's in it...? :hmm:

might as well and get rid of those whimpy speakers you're currently using. Hey, let's get some REAL volumn going here. :D

Zilch
08-04-2005, 12:54 PM
Hey, let's get some REAL volumn going here. :DI gotta be careful not to trigger a seismic event in Kansas. :p

Actually, it came without drivers from subwoof. Wasn't cheap movin' that from NY to here. :(

BUT, I have a pair of E155-8's I'm gonna load in it today. BB6P says I'd get about 3 dB more SPL with 2242H's, and probably even lower distortion. No retuning necessary. I don't have a pair of those, tho....

The results will be reported here: http://earthquake.usgs.gov/

:)

JBLnsince1959
08-04-2005, 01:59 PM
I gotta be careful not to trigger a seismic event in Kansas. :p

Actually, it came without drivers from subwoof. Wasn't cheap movin' that from NY to here. :(

BUT, I have a pair of E155-8's I'm gonna load in it today. BB6P says I'd get about 3 dB more SPL with 2242H's, and probably even lower distortion. No retuning necessary. I don't have a pair of those, tho....

The results will be reported here: http://earthquake.usgs.gov/

:)

:applaud: :rotfl:

Man, I've GOT to make a trip out to Ca. and see everyone...to many goodies out there

Zilch
08-04-2005, 10:48 PM
a) View inside from one of the end chambers. Box is face down; end of duct in opposite chamber peeks in at the right. Gaskets in place, ready to load.

b) E155-8 Loaded.

c) View in through one of center chamber ports shows motors back-to-back. Only about 1" separates them. Might have to shim 2242H's to make 'em fit.

d) RTA measures actual performance. Mic at 1 M aimed midway between center chamber ports (where the action is). Mackie amp low pass at 125 Hz. Low end bars are 20, 22.5, 25, 28, 31.5, 35.5, and 40 Hz.

It plays better than JBL spec, basically. +/- 1.25 dB here from 28 to 100 Hz, down maybe 7.5 dB at 22.5 Hz.

As subwoof earlier observed, these are very efficient. Just a coupla watts rattles doors and windows throughout the house. That gets boring pretty quickly.

They have full bass tonality, i.e., no boominess. They don't do subsonic like paired B460's do tho. Could give 'em a little boost down there, probably, but only so long as I don't crank it.... :p

JBLnsince1959
08-05-2005, 05:29 AM
a)
They have full bass tonality, i.e., no boominess. They don't do subsonic like paired B460's do tho. Could give 'em a little boost down there, probably, but only so long as I don't crank it.... :p

could try a pair of 2245's and a little eq. for more subsonic stuff if needed. the E-155's aren't subwoofs in the true sense.

JBLnsince1959
08-05-2005, 06:34 AM
Maybe I've miss this ( sorry if I have), but what are these tuned to.

also, try running the software with some 2245's. Those were the big sub's JBL made. E-155's are more of a musical instrument speaker ( but then you know that) :D

Zilch
08-05-2005, 09:29 AM
It's instructive, actually. While we don't think of E155 as a true subwoofer, and it certainly doesn't play like one in traditional alignments, the T/S parameters are very similar to 2240, the drivers that came standard in this box. Same with 2242H. What can be achieved with box design is quite amazing.

Also, we think of bandpass boxes as the boomy-sounding fabrications installed in pickup trucks. Having heard the surprising Control SB-5, I expected this TCB configuration to distinguish itself from those conceptions. It certainly does. Once again, the JBL specs on the design are reliable to the last decimal place. :D

The tuning is on the spec sheet. 24 Hz for the outer chambers, 68 Hz for the center one. Now that I know how good this is, I'll play a little with box designs for 2245. BUT, I'm most tempted to try the designs proposed by GordonW using 123A's or LE14's now that I know how they go together and operate. The one for LE14's is more appropriately scaled for HT and the drivers are plentiful. Check both out here:

http://audioheritage.org/vbulletin/showthread.php?t=3922

Zilch
08-06-2005, 03:41 PM
If we're not living on the edge... we're taking up too much room. :D :bouncy: :bouncy: :bouncy: :bouncy: :bouncy:

Floors are bouncin' here.

Zilch dubs the 4688 "impressive".... :rotfl:

subwoof
08-06-2005, 11:10 PM
Nice to see someone was able to use this monster to it's intended duty.

Um..I know of 2 more of these still in the original factory boxes at a freinds garage.......his family has expanded which means the wife wants the garage back....:o)

anyone interested??? PM me

sub

johnaec
08-07-2005, 06:50 AM
......his family has expanded which means the wife wants the garage back....Use 'em for bedrooms for the kids. :p

John

loach71
01-06-2007, 03:10 PM
Triple Chamber Bandpass sub uses dual 18" drivers in "Push-push" configuration. Motors in center chamber.

Drawing shows center (red) and outer (blue) chamber details separately. Bracing comprising center chamber "port tubes" only shown.

[Oodles more bracing therein. :p ]

Tech note here: http://audioheritage.org/vbulletin/showthread.php?t=6289

JBL Lit here: http://www.jblpro.com/pub/obsolete/4688.pdf

This looks to be quite the subwoofer. Do you have any more dimensional information on the center chamber? I am interested in building four of these beasts -- I just acquired qty. 8 JBL 2245H drivers from a government auction. Do you think these drivers would work OK in this particular enclosure?

Thanks!:bouncy:

Zilch
01-08-2007, 06:56 PM
Do you think these drivers would work OK in this particular enclosure?My initial thought was "No way," but first looks in BB6P say 2245H will work fine.

Subwoof knows where there's a couple available for sale. Paying the freight and acquiring an original to build from would be my suggestion. That way, you can try it out first to be sure, too.

If you do that, prepare detailed construction drawings for the benefit of the forum.

I'm still looking for a 4685 and a 4682. Those smaller ones would also be fun to build. I have a preliminary design for 4685 in BB6P that I may build while the search continues.... :thmbsup:

loach71
01-09-2007, 02:08 AM
My initial thought was "No way," but first looks in BB6P say 2245H will work fine.

:applaud:Subwoof knows where there's a couple available for sale. Paying the freight and acquiring an original to build from would be my suggestion. That way, you can try it out first to be sure, too.

If you do that, prepare detailed construction drawings for the benefit of the forum.

I'm still looking for a 4685 and a 4682. Those smaller ones would also be fun to build. I have a preliminary design for 4685 in BB6P that I may build while the search continues.... :thmbsup:

I'm modeling this thing with BB6 Pro - but I only get gibberish on the center chamber and its vents. I've tuned the two outer chambers to 24 Hz ... and your 4" x 14" vent fits the model. I've tuned the center chamber to 68 Hz -- but BB6 Pro says NO WAY for the 4" x 14" vent. I must be doing something wrong..:banghead:


The 4688s for sale on E-Pay are in upstate N.Y. and the seller wants $400 each for the cabs with no drivers. Shipped to rural Montana, the costs would be huge. So that is why I am doing the math... Sweat and sawdust equity for the impecunious..

Here are my initial results: (don't laugh too much!)

Internal dimensions quoted.

Outside chambers - 25.5" x 25.5" x 19.5" - single vent 5.991" I.D. x 14" long

Inside chamber - 25.5" x 25.5" x 22.6" - vent data comes out totally silly!:banghead:

After I get this worked out I'll publish the complete data set and cut sheet info.

Any insights would be welcome.... thanks in advance for your kind help offered to this n00b...

4313B
01-09-2007, 02:16 AM
I just acquired qty. 8 JBL 2245H drivers from a government auction.Nice! That's four pairs of 4345's. :)

8.0 surround sound :p (won't need subs) ;)

loach71
01-09-2007, 02:21 AM
Nice! That's four pairs of 4345's. :)

8.0 surround sound (won't need subs) ;)
With the right enclosure and all my old BGW 750s I might be able to generate the "brown note" <YIKES>:jawdrop:

Guido
01-09-2007, 03:30 AM
I felt (heard?) those beasts once in a club. Believe it or not 4 each stacked per side.
It was definitely an "adventure".

YEAH! Those where the times!

Zilch
01-09-2007, 08:54 AM
I believe I paid $400 to have it shipped across the country.

The ports are 8" diameter, not 4".

mikebake
01-09-2007, 09:12 AM
And why do you suppose JBL dropped these from their line-up?

loach71
01-09-2007, 09:22 AM
I believe I paid $400 to have it shipped across the country.

The ports are 8" diameter, not 4".

I'll post my BB6P model here later today....

AAHHH -- a light switches on :idea: in my n00bish brain!

Thanks for the help Zilch!

Zilch
01-09-2007, 11:20 AM
And why do you suppose JBL dropped these from their line-up?They dropped them because of a Bose patent infringement allegation.

That patent having expired, the TCB approach has crept back into some recent JBL designs.... :thmbsup:

mikebake
01-09-2007, 11:36 AM
They dropped them because of a Bose patent infringement allegation.

That patent having expired, the TCB approach has recently crept back into some recent JBL designs.... :thmbsup:
No way! Where'd you learn that? I figured it was a performance, or performance vs. cost issue. Not to mention weight.

Zilch
01-09-2007, 12:01 PM
No way! Where'd you learn that? I figured it was a performance, or performance vs. cost issue. Not to mention weight.http://audioheritage.org/vbulletin/showthread.php?p=38782#post38782

Zilch
01-09-2007, 12:20 PM
BB6P model 4688 now appended in post #31, above.

Here's an unverified version 4685 for 15" woofers; never had one to actually measure, tho. Response w/2226H pair.

Compare to original w/2225H specs:

http://www.jblpro.com/pub/obsolete/4685.pdf

subwoof
01-09-2007, 01:22 PM
I spoke with Mark Gander at the 1997 NAMM show ( ORIGINAL tent sale ) about these. That's where I bought the three of them.

There is no love for Dr Bose in northridge....

:D:D:D

sub

Originally Posted by Zilch http://audioheritage.org/vbulletin/images/buttons/viewpost.gif (http://audioheritage.org/vbulletin/showthread.php?p=142624#post142624)
They dropped them because of a Bose patent infringement allegation.

John
01-09-2007, 01:33 PM
Hi Subwoof do you still have those cabinets?

Zilch
01-09-2007, 02:07 PM
http://cgi.ebay.com/2-JBL-4688-Subwoofer-cabinets-2-X-18-NEW_W0QQitemZ180071491404QQihZ008QQcategoryZ47094Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem

loach71
01-09-2007, 04:11 PM
I believe I paid $400 to hav e it shipped across the country.

The ports are 8" diameter, not 4".

Thanks for the screen shots Zilch. I plugged in you values and the ports made sense. The darned software must not like me :screwy: Time for some Jack Daniel's to clear this mental fog...

Then it's tablesaw and router time... sober -- of course!

4313B
01-09-2007, 04:37 PM
Time for some Jack Daniel's to clear this mental fog... Then it's tablesaw and router time...Yee Haw!!!:applaud:


sober -- of course!Oh... :( I thought we had a new home video brewing there for a moment...

loach71
01-09-2007, 04:55 PM
Yee Haw!!!:applaud:

Oh... :( I thought we had a new home video brewing there for a moment...

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=21849&stc=1&d=1168389640

Well gosh, golly, gee -- I guess my Yew-All Southern heritage has shown up agin! My Montana buddies always thought I was more right-wing than them. ;)

I'm going to change the design a tad -- the internal dimensions will stay about the same, but I will be using 2.25" wall thickness -- .75" Baltic birch plywood laminated to .75" MDF laminated to .75" Baltic birch plywood. That should make a box with stiff enough walls and high enough wall resonance frequencies. They will also be theft proof - except for Paul Bunyan.

4313B
01-09-2007, 05:03 PM
I name the enclosure the 'DAISY DUKE" twin 45's heh heh heh

Sounds good to me!

loach71
01-11-2007, 07:04 PM
I've started laminating the .75" baltic birch plywood and the .75" MDF.
Looks like 2 sheets baltic birch and one sheet MDF per enclosure..
They will be heavy suckers. Ohh my acheing back. Thank god for 4" casters..
Plans are to run one BGW 750C per enclosure.... I have a few of these
amps just lying around -- don't want them getting lazy!

:dj-party:

Zilch
01-11-2007, 07:58 PM
Those'd be bigger sheets than we can get around here.... ;)

loach71
01-14-2007, 04:29 PM
Those'd be bigger sheets than we can get around here.... ;)

Everything is BIGGER in BIG SKY COUNTRY...
Even California expats are moving here...

jbl_man_uk
01-15-2007, 02:10 AM
I have come across lots of these 2x18 TCB subwoofers for sale over the past few years,mainly ex-club and install,and funny thing is,they are ALLWAYS either empty,or blown,or without the original drivers,which leads me to think that they are quite severe on drivers when pushed hard resulting in failures...they do go quite low,but have no bass punch at all.not one of JBL`s better designs.

Zilch
01-15-2007, 09:40 AM
they do go quite low,but have no bass punch at all.

Punch's not their job, mon.

They just supposed to relocate stuff and make ears bleed.

Yeah, I'm sure they REALLY suck.

Lemme see if I can blow this one up.

[I wanna put 2242Hs in it, anyway.... :p ]

loach71
01-15-2007, 11:13 AM
I've managed to construct two test versions (made of MDF) of the 2245H variant of the woofer described by el-Zilch-O in this article. The bass output is prodigious. It compares favorable with Greg Timber's ported monster (2245H loaded). It seems more efficient than the ported design - by about 6 dB in its passband. I think I will now start on the baltic birch- MDF laminated final versions of this sub -- it seems to move the earth on Dolby Digital / dts LFE tracks. Standing on end, a 30" footprint is not that intrusive...

:applaud: Many thanks to el-Zilch-O:applaud: for help with the BB6 Pro design -- maybe I should learn to read...:o:

Zilch
01-15-2007, 11:26 AM
I was HOPING you'd do a test box first before committing it to the full laminated construction, as 2245H is unexplored territory using this design.

Glad it's working for you.... :thmbsup:

loach71
01-15-2007, 03:53 PM
The test 4688 loaded with 2245H drivers compares favorably with Greg Timbers' 2245H ported sub (12 cu ft extended bass shelf). My first impressions are the following:

* The 4688 is more efficient than the ported box. (about 6 dB overall in the passband mentioned below)
* The 4688 gives a drier, more analytical bass.
* The ported sub seems to give a little more extended bass on the low frequency end of the passband - which is probably due to the EQ Greg recommends. When I supply the same EQ on the 4688 clone, the low bass seems about the same.
* My 1/3 oct spectrum analyzer and calibrated mike (el-cheap-o DOD unit) doesn't see much difference in the response in the passband 20 Hz to 90 Hz, using 48 dB / octave high and low pass filters at the above frequencies.

Overall the 4688 seems the winner due to better efficiency and its 30" square footprint. I never got the 2245s in the 4688 clone to bottom out - even though I was using a bridged BGW 750C per woofer...

Now for the heavy work on the laminated enclosures... and lots of Jack Daniel's for the woman -- it is great WAF lubricant...

OGHinz
04-09-2007, 04:45 AM
Is the JBL 4788 identical to the 4688?

loach71
04-09-2007, 06:06 PM
Is the JBL 4788 identical to the 4688?

Never heard of that model. Seached the jblpro website and came up with nothing.

Now that spring is here in Big Sky Country, I am doing the finishing on the qty. 4 (yes Zilch -- FOUR) 4688 TCB subs. I am using Purple Heart veneer then followed by multiple coats of Tung Oil. Should be finished in a month. It has been a long journey - but the sonic results are quite pleasing. Thanks again for the BB6 Pro help.

JBL 4645
04-14-2007, 02:34 PM
So thatís what looks like inside I do love a good peek show. I would like to own just one of those I did have its baby the JBL Control SB-5 (TCB) many years ago
The only time I heard and felt the (TCB) range was at the Odeon Leicester square Last Action Hero 70mm Dolby SR (1993) and they had two of those beasts behind the screen and even in a large auditorium they shock the seats when Slater, comes crashing though the wall in 4x4! There also THX approved! :)

ďItís a mean, mean mother from outer space.Ē:rockon1::banana:

Zilch
04-14-2007, 03:46 PM
Somebody over there across the pond recently posted that two of them were available empty, and they only wanted one.

May be your chance! :thmbsup:

http://audioheritage.org/vbulletin/showthread.php?t=15719

discus96
09-05-2007, 02:29 AM
Following your suggestions and this thread I will start my "JBL 4688 Clone project"

I have just bought on e-bay two recently reconed 2240H and the "TCB Subwoofer system" looks just perfect for my HT and Music application.

Thanks to Zilch drawings, pictures and indications, I'll try to produce an exact copy of the 4688.

Dimensions are very well indicated in his BB6 pages, my doubts are regarding the ducts lenght and dia so I picked Zilch picture of the 4688 inerior and put few lines to see If I understood correctly.
Please check if this is OK.

Thank you

Zilch
09-05-2007, 01:08 PM
The duct length is 14" to the outside, of course.

Where you have written "No Ducts" is the blind closed box shown on the drawings. While there are no ducts there in the conventional sense, that box in combination with the bracing (left tip of your port dimension arrow) serves to constrict the areas (volumes) just inside the ports such that they function as ducts.

The BB6P sims show the approximate equivalent effective duct length, which for the center chamber is modest in comparison to the outer chambers....

4343
11-05-2007, 08:33 PM
Is the JBL 4788 identical to the 4688?
Found this at: http://forums.audioholics.com/forums/showthread.php?t=34477&page=2
Seems to be a cine version.

I started sawing scraps for the 2226 version, 2 short sides are 1" MDF, back and ends are 3/4" ply, baffles are 3/4" ply laminated to 5/8" MDF, removable panels are 5/8" MDF laminated to 3/4" ply. Not quite done with the removable side yet, but the rest of the pieces are cut and ready to glue up this week.

All I have to test with is 2205B's... Could the low chambers be tuned a little lower if I was to put 2235's in it?

Thom
11-06-2007, 06:27 AM
It felt like someone fired up something like that over here last week. Fortunately it was for only a few seconds and at reduced volume. They kept it under a 6.0.

4343
11-07-2007, 10:18 AM
It felt like someone fired up something like that over here last week. Fortunately it was for only a few seconds and at reduced volume. They kept it under a 6.0.

That wasn't me! Although, come to think of it, it was the day I got my "new" SB-5 running, maybe the straw that rattled the fault loose?:D

Wolf
01-14-2008, 02:48 AM
Hello,

a happy and healthy new year to all!

In the meantime i am a happy owner of an old 4685; at least i believe it's a 4685...

Here is a picture of that cabinet. Does anybody know this box? There is no label on the backside but i'm sure it's an original JBL cabinet. May be a predecessor of the established 4685?

Best regards
Wolf

Zilch
01-14-2008, 11:55 AM
Three chambers inside, with mounting for two drivers in the middle one?

Wolf
01-14-2008, 02:29 PM
Yes. I hope you can identify the cabinet with the following fotos.

Thank you in advance for your help!

Best regards
Wolf

Zilch
01-14-2008, 05:23 PM
It certainly looks right, but the square port was apparently not used on the production models.

The metal bracing between the woofers is of considerable conceptual interest. Until we see an actual production version, or plans for it, we won't know if that was part of the final design.

It would be interesting if someone would order a pair from the JBL Pro custom shop. This might generate some head-scratching in Northridge.... :p

johnaec
01-14-2008, 05:48 PM
Those look like 15" baskets to me - JBL's 18's have a completely different spoke assembly, don't they?

John

Zilch
01-14-2008, 07:03 PM
Those look like 15" baskets to me - JBL's 18's have a completely different spoke assembly, don't they?I believe Wolf said he had the 15" version, 4685.

Three sizes were available, actually. Links to the smaller ones are in this early post:

http://audioheritage.org/vbulletin/showthread.php?p=65266#post65266

Wolf
01-15-2008, 01:05 AM
Hello,

yes, it's the 15"-Version. I bought it as a 4685. Later i found out that the dimension are quite different to the dimensions stated in the flysheet (mine: H/W/D=57/114/87cm; original: H/W/D=75/125/51cm).

There is no model code at the input panel. But it is an original JBL-panel.

The quality of the construction is absolutely professional and analog to my other JBL gear.

The bracing looks good but i am not shure being original. Maybe someone of my predecessors had a good idea...

ASAP i will offer better pictures of the cabinet.

Best regards and thank you for your help
Wolf

Wolf
01-16-2008, 09:51 AM
Hello,
here are some new pictures. I hope they are not too large, sorry if so.

The front, the back and the rear input panel. There is no model number written on the panel. Funny.

Thank you very much in advance for your help.

Best regards
Wolf

Rudy Kleimann
01-18-2008, 10:52 AM
Looking at the pics, it sure does look like something built by JBL. Perhaps it was a custom shop cabinet to fit in a certain space?
Does it have the right metal grilles over the openings? Do they look like they were installed professionally?

RE: the metal braces and that square hole that Zilch commented on: seems to mee like it is an access port to install the woofers and braces on the backside, and then you put a cover over it...?

hmolwitz
01-18-2008, 01:15 PM
The center port looks correct, this design is 3 chambers with port(s) on each chamber, it is just square instead of round as the literature states.
It looks like the area of the center chamber porting is equal to the area of the outer chambers ports combined, which makes sense to me.
Harry

Wolf
01-20-2008, 07:04 AM
Hello,

there are no metal grills covering the openings; there ist no grill at all.

The cabinet has two access ports, one above and one downside, leading to the backchamber (of course). At the front of the backchamber for the two 2225 is one square port (18,7*18,7cm, length 100cm). The volume of the backchamber is about 75litres (net).

The frontchamber of each 2226 has about 155litres (net) and one round port with a dia of 15,1cm and a length of about 18,3cm.

@Zilch:
What kind of software do you use for the simulation of the 4685 and the 4688? I would like to simulate my "4685" and compare it to your simulation.

Thank you all for your advice and best regards
Wolf

Zilch
01-20-2008, 06:36 PM
BassBox 6 Pro. It has a triple-chamber bandpass option.... :thmbsup:

Wolf
07-04-2008, 01:37 AM
Hello @ all,

it seems to me i'd found the big brother of my custom JBL 4685:

http://cgi.ebay.de/JBL-Bandbassgehaeuse-2X18_W0QQitemZ300238779105QQihZ020QQcategoryZ75905 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It is a TCB cabinet too, but with square hole instead of the round one's of the 4688/4788. The same as mine (see above, 4685/4785), but for 18" driver.

Is there anybody who can tell me something about these cabinets?

Best regards and thank you in advance
Wolf

subwoof
07-04-2008, 07:45 AM
Looks like JBL ( harman ) had a cabinet shop and sold low-profile versions of the TCB's in the EU. The input plate wood cutout is the same as all the concert series cabs I bought back in '97 and the plate / jacks / printing look identical.

It sure would be nice to get plans for the cabinets since getting LF boxes under the stages and such is an advantage in cramped installs.

At the current price you can't go wrong and if you get it please share the specs!

sub

Wolf
07-04-2008, 10:37 AM
Looks like JBL ( harman ) had a cabinet shop and sold low-profile versions of the TCB's in the EU. The input plate wood cutout is the same as all the concert series cabs I bought back in '97 and the plate / jacks / printing look identical.

It sure would be nice to get plans for the cabinets since getting LF boxes under the stages and such is an advantage in cramped installs.


That's really a good point!

But why don't they have any serial nummber?



At the current price you can't go wrong and if you get it please share the specs!

sub


I'll tell the spec's, for sure, if i buy these big cabinets. But i don't know how to explain my wife that i must have one more pair of big cabinets. We have three big rooms full off JBL and Altec; maybe she is running out of humor...

Best regards
Wolf

subwoof
07-04-2008, 11:24 AM
I believe that only items that were in regular catalogs / price lists or such had numbers.

At the '97 NAMM show I bought some cabinets that were part of the Architectural series and because they had many finishing / component / hardware options the exact model numbers were just too long for the nameplates ( and had no serial numbers )

Even the concert series had hand-punched serial numbers so maybe it was not an option.

Tell the wife that your hobby *could* be old VW engines, beer steins, chainsaws or even motorcycles....at least your stuff is indoors and not on the lawn.

"das ist schade"

sub

Wolf
07-05-2008, 03:24 AM
I believe that only items that were in regular catalogs / price lists or such had numbers.

Okay, i understand. I was wondering, because my own little cabinet has no serial number too.


Tell the wife that your hobby *could* be old VW engines, beer steins, chainsaws or even motorcycles....at least your stuff is indoors and not on the lawn.

:D If i tell her this point, she will laugh and remember me at the time, about 30 years ago: my hobby were motorcycles and i had some of these... Later it was a VW Bully. Now i play drums in 4 bands, so about 4 evenings a week i am drumming. Excluding the gigs at the weekends. :(


"das ist schade"
May be not... If i can't buy these cabinets, i'll ask the highest bidder to give some informations.

Best regards
Wolf

JBL 4645
11-12-2009, 02:46 PM
I see a few are taking a peek at this thread, we know your names…:D so I had one question.

Why doesn’t JBL resurrect this classic JBL beast? It would sound so much awesome in THX cinema, because I want mindless out of control low frequency vibrations!:bouncy:

subwoof
11-12-2009, 04:16 PM
I will be building clones of these sometime next summer when the new cabinet shop comes online...stay tuned...

sub

Zilch
11-12-2009, 05:10 PM
12" and 15" too, I hope.... :D

JBL 4645
11-12-2009, 05:12 PM
12" and 15" too, I hope.... :D

Whatís wrong with the 18Ē JBL?:D

Zilch
11-12-2009, 05:18 PM
Nothin' four guys and a forklift can't handle.... ;)

JBL 4645
11-12-2009, 05:20 PM
They are large! I stood next to one at the night club at Tower Park back around the early 1990ís it was a monstrosity of a size.:blink::D

subwoof
11-12-2009, 05:25 PM
I have the 18 and 12 versions here...the 15's are IMPOSSIBLE to find. Find me one and I will clone it.

Also a special baffle mod on the 12 version so it can mount the 2217H ( 14 ) will be made. This would work very well with my array cabs I think.

So has *anyone* seen a 15" version?? let alone have one for sale??

sub

JBL 4645
11-12-2009, 05:57 PM
I have the 18 and 12 versions here...the 15's are IMPOSSIBLE to find. Find me one and I will clone it.

Also a special baffle mod on the 12 version so it can mount the 2217H ( 14 ) will be made. This would work very well with my array cabs I think.

So has *anyone* seen a 15" version?? let alone have one for sale??

sub
Sub

How much will it cost with the building materials and your time as well to build a clone?

subwoof
11-12-2009, 06:18 PM
I cannot do any planning or building until the new shop is ready - due to a 7 month delay getting the building the place will be storage only until spring.

sub

JBL 4645
11-12-2009, 06:36 PM
I cannot do any planning or building until the new shop is ready - due to a 7 month delay getting the building the place will be storage only until spring.

sub

I see. You couldnít have guess as to how much, just for a bit of fun.

Rudy Kleimann
11-12-2009, 08:53 PM
I will be building clones of these sometime next summer when the new cabinet shop comes online...stay tuned...

sub

Tuned... to what frequencies?:rotfl:

BTW- The "Coming to a fault line near you" title line was clever and on-target too, eh Zilch?

Seriously, the revival of this thread is very timely indeed, considering what I've been dreaming up lately. I need to refresh my memory on this before considering any 2245H's for "subsonic" work.

Eaulive
11-17-2009, 01:10 PM
or better yet, make one and put cushions on it and sit on it while watching the movies... girls I think would REALLY like that......

When we just got married, my wife used my two Cerwin-Vega 18" bass bins as a couch, she made some cushions for them and it looked OK for her, I didn't want to get rid of my system so she worked around it :applaud:

I was going to post a picture but I realize the only one I have is when she's laying on them, kind of indecently.
I won't post it because you probably won't pay attention to the cabinets anyways :bouncy:

mikebake
11-17-2009, 01:41 PM
Oh, go on and post the photo and we'll work around it.

Eaulive
11-19-2009, 11:28 AM
Oh, go on and post the photo and we'll work around it.

I don't want to get banninated from the site :D:D:D

louped garouv
11-19-2009, 03:33 PM
I don't want to get banninated from the site :D:D:D
for posting a lovely picture of your... speaker?


;)


J/K

hjames
11-19-2009, 06:23 PM
I don't want to get banninated from the site :D:D:D

We are yur frenz - really, its ok - please show us yur speakerz ...

Eaulive
11-24-2009, 01:11 PM
We are yur frenz - really, its ok - please show us yur speakerz ...

I rather avoid any kinky comments about her rear loaded horn... :D:uhmmmm:

4343
11-27-2009, 11:44 AM
Nothing horn loaded here, unless you count the 2402's in the background... This was made following Zilch's BB6 sim from earlier in this thread. Currently loaded with 2225H, looking for a pair of 2226H for it.

Halfway through gluing it up I decided to put wheels and handles on it just to be able to move it! Casters might be a better way to go, for reference, those are 3" wheels!

I had to coat the inside of the handles and wheels with a thick coat of Liquid Nails (thick glue) to get a good seal. The carpet glue also acts as a good anti-resonance layer...

Sounds Great! Solid to 30Hz, drops like a rock below that.

BTW, those floor monitors (15's with 2402's) are due for an EWAVEing as soon as the 6X6 waveguides arrive.

JBL 4645
11-28-2009, 08:47 AM
What does (TCB) stand for! Terminating Chest Banger! :D

Nice looking TCB you have got there and the wheels make it easier to move it around as that is one hefty heavy enclosure!

Allanvh5150
11-28-2009, 11:49 AM
Triple Chamber Bandpass. The Patent is owned by Bose I believe. Did you not know that?...............

Allan.:)

Eaulive
11-28-2009, 04:40 PM
Triple Chamber Bandpass. The Patent is owned by Bose I believe. Did you not know that?...............

Allan.:)

Apparently the patent has expire...

JBL 4645
11-28-2009, 05:20 PM
Triple Chamber Bandpass. The Patent is owned by Bose I believe. Did you not know that?...............

Allan.:)

I know that I was just having a laugh with the (TCB) name. Yeah I seem to recall someone mention Bose in the past. Please wash your mouth out with bleach! :D Bose! lol


Apparently the patent has expire...
Oh thatís good news so JBL can resurrect it. :D

Allanvh5150
11-28-2009, 05:54 PM
Please wash your mouth out with bleach!. :D

Don't need to Ash. I have used and installed every bose speaker system over the years and have always found them to perform pretty well. However, as with every speaker system, if they are used outside of thier design parameters they will fail to do a good job.

Allan.

analog addict
08-09-2012, 01:21 PM
A pair of 4685's for less than the cost of the drivers. I'll lift a glass to your memory when the dust settles.....

Don't mind my non JBL center channel....:D

http://i443.photobucket.com/albums/qq158/analog_addict/audio%20tech/3760fded.jpg

http://i443.photobucket.com/albums/qq158/analog_addict/audio%20tech/3bb37566.jpg

Oldmics
08-09-2012, 02:30 PM
Thats just one side of the system-right ??? :confused:

Oldmics

Lee in Montreal
08-09-2012, 02:51 PM
How tall are the A4s? Let me guess, 8ft tall. That's a huge center channel :applaud:

Krunchy
08-09-2012, 03:31 PM
Thats Great! :applaud: I absolutely love it (dig the poster too), how does it sound...........to your neighbors.
Whats that, 10' ceilings?


Enjoy! :D

analog addict
08-09-2012, 04:51 PM
Thats just one side of the system-right ??? :confused:

Oldmics

No, it really is my center channel. Here is my left channel. The right is a mirror image....:p

http://i443.photobucket.com/albums/qq158/analog_addict/Altec/c3019e64.jpg

Yours truly at about 6' added for scale. And yes the ceilings are 10' in the ol mancave....

http://i443.photobucket.com/albums/qq158/analog_addict/Altec/7b9464d1.jpg

Lee in Montreal
08-09-2012, 05:17 PM
Impressive. Can I suggest do to "something" so that you don't breath all that fiberglass. It's not good for your lungs. ;)

NickH
08-15-2012, 06:33 AM
So did anyone ever create finished plans for the 4688? Im thinking about building one.


Or is there just the BBpro screen shots?


Thanks,
Nick

Champster
05-10-2014, 07:43 AM
So did anyone ever create finished plans for the 4688? Im thinking about building one.


Or is there just the BBpro screen shots?


Thanks,
Nick


Anyone???

Phil Collins
03-19-2015, 08:52 AM
Anyone???


I've just finished building the 15" version using 2226H's.

Struggling with the port length though if anyone can shed some light :D

Will post some pics when i've finished the second one and had both painted