4333 layout/dimensions needed .....

[barkingdog]

Hey DIYers,

I have all the components for my DIY 4333-ish project. I'm using a 2235H, 2425J, 2405H, and 2312/L92 combo. I have the components for some home-built 3105 crossovers and I intend to bi amp the system using an Ashley active crossover between the LF and the MF/HF components.

What I don't have is dimensions for the cabinet or the layout and sizes of the baffle cutouts. Can anyone assist? I have searched the site but haven't found anything. Could be my search methods but any help would be appreciated. I'm figuring on a 5 cu ft cabinet so port info would be great too. My copy of Winspk is pooched ......

Thanks!

[remusr]

Here's the 4333B general model pdf from jbl pro website.

[barkingdog]

Thanks Remusr, I already have that document. Are the dimensions of the cabinet the outside or inside dimensions?

What I'm really looking for is the locations and sizes of the holes on the baffle. I can probably just lay them out in a way that makes sense but I was hoping for specific cutout sizes and locations. I'm sure somebody on this site has built a similar cabinet before, I'm hoping they might have some plans to share.

Thanks again.

[mech986]

Hi,

Original Brochure 4333A link as JPG's here at Lansing Heritage:

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1977-4331-4333.htm

Dimensions:

http://www.lansingheritage.org/images/jbl/specs/pro-speakers/1977-4331-4333/page4.jpg

Same from JBL Pro as Pdf's for 4333B model:

http://www.jblpro.com/pub/obsolete/4331b_4333b.pdf

Hope this helps. You should contact member riessen as he has done a lot of DIY and I think has the dimensions and cutouts.

See this thread:

http://audioheritage.org/vbulletin/showthread.php?t=5907

Regards,

Bart

[saeman]

I will look thru my notebooks to find the drawings I have for this cabinet and baffle. Give me a few days to find them. I will not have time to refine them so you'll have to sift thru my notes and drawings to determine what you need.

[northwood]

4333 is great

[speakerdave]

Here's a photo with the woofer out:

[speakerdave]

Dimensions:

Overall:
Height: 30 5/8"
Width: 24 3/8"
Depth: 17 9/16" from back edge to nose of bevel on the front.

Baffle details: Made of 3/4" fine-ply stock
Width: 22 1/4"
Height: 28 1/2"
Backset from nose of the edge: 3/4"

Location of holes: All distances are from baffle edge with my ruler butted up against the inside of the nosing.
Woofer: 3" from the right, 2 1/8" above the bottom.
Tweeter holes: 1 1/2" from the side, 5" down from the top
mid horn: 4 1/2" down from the top, centered on baffle
These three holes are all centered on the same horizontal line (with speaker upright).

You can get the hole diameters from specs or from your components, and then locate the centers.

Port: 4 and a fat 1/8 inside diameter; it's 4 1/2" long; 1 3/8" from the side and 2" up from the bottom.

[speakerdave]

The back is as you see it; the dimensions are the same as for the baffle.
The stock is 3/4" MDF (I guess). The stock for the sides measures a fat 1 1/16"; it might be a metric size--25mm.

The upper hatch gives access to the back of the horn. The lower one is for the entry panel, obviously. You may want to size and locate these for yourself, though here are some measurements:

The compression driver hatch is 8 1/8" by 9", 2" down from the top and it is centered in the baffle side to side; it's corners are radiused as you can see. I have not had this off, but I think the outer screws mount the hatch and the inner ones mount the cradle for the driver, which is also padded with two layers of the thin foam padding you will often see thrown into a box by your favorite ebay seller.

The cutout for the input posts is 4 1/4" by 5 1/2", but you may want to make you own arrangement here.

The inset of the back is 1/4"

The larger screw heads with washers (one has a tag saying not to remove them) are for mounting hanging hardware. The large Philips head screws you see in the back and in the baffle are also related to that.

[speakerdave]

The cabinets are veneered on all four sides, not a necessity if you plan on always using them vertically, and an integral base might be a worthwhile addition. With the cabinet sitting on the floor the tweeter and midrange are two low (unless you sit on the floor too; then it's perfect). You will notice that the arrangement of the midhorn and tweeter openings permits both mirror imaging in the vertical position and also horizontal positioning, which, with the tweeter right over the midhorn, may actually produce better imaging.

If you need more photos let me know. I can't do much with the foilcal with my digital camera, but if you want to try and have one made, let me know; I can get a high definition shot of it with a film camera and get it to you.

[speakerdave]

Nosing profile and other details.

I can't see what the cabinet joinery details are, although riessen probably knows. I'll sketch the nosing tomorrow.
And then there's the grille frame. It's not too soon to order your grille cloth from Mr. Zed.

By the way, you should look into building the updated version of the 3133 crossover for this speaker; here's the thread: http://www.audioheritage.org/vbulletin/showthread.php?t=166&highlight=3133

The edge detail on the front is interesting because the inset of the baffle is greater that the apparent depth of the beveled piece. It may be that there is no solid walnut trim piece here, but I am not going to dig out any paint to find out. It could be that the front of the side, top and bottom panels is beveled and veneer applied. I am trying to get a drawing installed here, but I am not adept with the software. Inset of baffle is 3/4"; angle of bevel is 118 degrees from the plane of the side or top/bottom. The bevel distance is 1". It is not sharp at the front; there is a 1/8" flat running along that edge. The extension of the bevel from the edge of the casing panels is 7/16". Not very clear, I know, but the drawing, when I can get it posted, will help.

[speakerdave]

Interior photos: Several shots of the interior arrangements of the bracing and hardware. The bracing is made of 1" by 2 1/2" stock, and it feels like it was kiln dried, so I wouldn't ask green lumber to do this job (that is, don't just use scraps of 2 x 4 unless it's been drying for a few years and you can cut and plane it square and true). Each panel has two braces which divide it roughly into thirds of its long dimension, except the back, whose braces are vertical. There is some deviation from exact thirds to provide offset of the braces in the corners where they meet at the top and bottom of the back. Everything is glued and screwed and then covered with wrap-on insulation (except the inside of the baffle). As you can seen, the baffle was sprayed next.

[4313B]

What I don't have is dimensions for the cabinet or the layout and sizes of the baffle cutouts. Can anyone assist?

That's exactly what I like to see posted in response Speakerdave. :applaud:
Thanks.

[saeman]

Keep the faith. I'm still looking for one of my notebooks that has all of my drawings for this enclosure. I'll look again tonight. Hopefully it will surface as it has other info that I don't need to lose. My drawing will give you the complete baffle layout with location of all holes.

Baffle and back were 3/4" baltic birch from JBL. Here's some pics that may help in the interim. I used MDF for the backs so the screws on the back show where I screwed thru the back into the braces. JBL screwed the braces from inside thru the brace and into the baltic birch back, and there are no screws showing on the back side.

Back with more info when I find my notebook.

Regards - Rick

[saeman]

I may not be completely correct saying that the back was always baltic birch. I seem to recall seeing a pair that had the back made of particle board. You may want to ask other owners to see what they have. Baltic birch is the only baffle material I have seen, on many many pairs. The cabinet top, sides and bottom were 1" veneered particle board.

My pics show the cabinets before they were complete. The finished product was an accurate copy of the factory cabinets. The back had the holes for eye-bolt hanging along with the steel brackets inside the cabinets. I believe my drawings show them too.

[speakerdave]

Here is the promised drawing. It is kind of hokey, I know. I've discovered in moving to my present version of OS X I have left my drawing software behind and have had to use what is offered in Word. I had to take it into PowerPoint and make a slide of it and store it as a JPG. There it is. I think it is clear enough for you to get the idea. The measurement for the set back of the baffle face from the outer edge of the nose is not clear for some reason; it is 3/4".

[Mr. Widget]

My pics show the cabinets before they were complete. The finished product was an accurate copy of the factory cabinets. The back had the holes for eye-bolt hanging along with the steel brackets inside the cabinets. I believe my drawings show them too.I have a couple of questions about the solid walnut moulding that makes up the nose as Dave is calling it. How did you hide the seam between it and the walnut veneered sides? How did you make the moulding?

A couple of years back I was going to build some 4355s and when it came time to make the moulding, I ripped some strips on the table saw and most of it warped pretty significantly due to inner stress that was released during all of the wood removal... I thought I might glue rectilinear blocks on the cabs and rout them in place, but I never finished the project so my problem went away.:)


Widget

[saeman]

Hi Mr. Widget: I attached a pic that should show the two different ways that I have done the trim molding on the Pro monitors.

The dwg. labeled "A" is how JBL attached the front trim. The trim was glued to the face of the finished cabinet and the visible seam was on the top, side, etc. The exposed top edge of the trim varies from near nothing to maybe 1/8". JBL was very good at blending the trim wood and veneer colors and the seam was barely visible. I have sometimes bleached the trim to match the veneer and had good results. You have to keep in mind that their cabinet shop had all the goodies and craftsmen on hand to make this problem go away.

The dwg. labeled "B" is how I do it (most of the time). I attach the trim (before the bevel is cut) to the bare cabinet and veneer over the trim. I then cut my beveled face and cut thru the trim and veneer at the same time. Since I'm a glue and hot iron veneer guy this gives me great results. 90% of my work is with 10 mil. paperback veneer so the exposed edge of the veneer is barely visible after the bevel is cut. I have a few colored permanent markers (made by Sharpie) that are intended for furniture touchup. With the wood not oiled the seam is usually not visible. After oiling is when you'll see it. Before applying oil I run a damp cloth across the edge to see what shows and about what shade the wood will be when oiled. I then take the appropriate marker and run it along the edge where the veneer meets the trim. Let it dry and then apply oil. Since the veneer is only 10 mil. I rarely see the seam and that's upon close inspection. From a foot away you'll likely not see anything.

If you're using phenolic backed or other types of veneer that are real thick, you need to use the method in Dwg. "A". With thick veneer I have had little luck hiding the edge seam that will show on the beveled face.

If I was using a vacuum bag and epoxy the thicker veneers would be easier to apply. Laying it down with wood glue and heat is a nightmare. I consequently always try to use 10 mil paperback.

Most of the pro cabinets I have seen have a face trim that is only 3/8" to 7/16" thick with a width coinciding to the thickness of the cabinet walls. It's very hard to cut this thin trim accurately and even harder to cut the bevel on it. Then try to clamp the beveled piece to the face of the cabinet without it rolling over under the clamp jaws. When restoring a pair of 4350B's some time back, I was cutting off the old face trim with a router and edge guide. I found myself cutting thru small trim nails. It appears that on some cabinets they did more than just glue it on.

Cutting the face bevel after the trim is applied and after the cabinet is veneered is a bit risky but gives the best results. I use a clamped edge guide in addition to the pilot bearing on the router bit, to keep the router from going anywhere it's not supposed to go. Along a 4 foot edge I may take 8 cuts before reaching the final depth. The first couple of passes will tell you if you're running "with" or "against the grain. If I'm running against the grain I usually take lighter cuts and pull the router instead of pushing. Having said all that I'll keep my fingers crosses. I haven't splintered a piece of trim yet but the risk is there. If that happens - cut it all off and go to Dwg. "A".

When doing this trim cutting I use my big 3HP porter cable router in-hand and a 1/2" shank bit - plenty of ass. The 30 degree bevel bit is expensive, maybe $30 to $40, and make sure it's sharp with no burned edges. If you mess up at this point :banghead:

Hope this helps - It's worked good for me on many cabinets.

Rick

[speakerdave]

Good ways to apply trim, for someone making a set of these speakers at home, but I'm puzzled by the fact that the inside of the nosing on my 4333A's is sprayed baffle blue. Why? When? I doubt they would do any spraying after the trim and veneer were applied just so the inside of the trim would be blue.

[saeman]

Good ways to apply trim, for someone making a set of these speakers at home, but I'm puzzled by the fact that the inside of the nosing on my 4333A's is sprayed blue just like the baffle. Why? When?

Dave: I'm not sure what you're asking. All the monitors I have seen have the inside of the trim painted to match the baffle. I assume JBL masked off the exposed walnut front edge and the rest of the cabinet (maybe with a mask frame sized for the cabinet) and shot everything blue, including a lot of the interior insulation. I'm only copy catting what they have done. The inside of my face trim is always blue too. I just don't spray the cabinet interior in the process.

[saeman]

I doubt they would do any spraying after the trim and veneer were applied just so the inside of the trim would be blue.

From what I have seen, the baffle was without a doubt painted after the trim was installed. I have seen cabinets with no evidence of a seam between the trim and cabinet where painted (no line, no crack, nothing). I would suggest that they either used a rigid frame type shield sized for the cabinet and then finish taped it in place or a paper masking frame taped in place. I have seen both methods used in cabinet shop production painting. Small amounts of overspray (if they encountered any) could easily be sanded off prior to applying oil.

[speakerdave]

It's just that the masking would be unnecessary if they were sprayed before the veneer and trim went on. I would think the spraying would be done in a special room. If the cabinets are veneered and trimmed when they are sprayed they would have to be taken into the room one at a time, masked off, handled by someone not into the paint, etc. It's not important; just wondering. I've looked at the brochures for the large monitor series, and they all seem to be that way as far as I can tell.

[saeman]

It's just that the masking would be unnecessary if they were sprayed before the veneer and trim went on.

You're forgetting that JBL wasn't a small time cabinet maker like I am. I quite often veneer after the cabinet is built - but JBL DID NOT. Their cabinets were made from pre-veneered stock. It's not likely they rolled their own veneer either (possibly) as they could easily order veneered stock, to their specifications, from the mill that supplied their material. The process of applying veneer on a large scale operation would have required a lot of expensive equipment, most likely cheaper to buy it already veneered. Somebody out there should be able to ask JBL to verify one way or another. Since their cabinets were assembled already veneered, they would have to mask the cabinet prior to painting the baffle - trim or no trim. So why not mask and paint after the trim was installed.

[saeman]

I've looked at the brochures for the large monitor series, and they all seem to be that way as far as I can tell.

Dave: You are correct. I have either owned, had possession of or closely inspected every 43XX series monitor. ALL have their face trim painted on the inside surface - black on studio grays and blue on walnut models.

[saeman]

Here's some info that should get you started. My notebook drawings were too busy with misc notes so I cleaned them up a bit.

If you're trying to closely duplicate the factory cabinet these will get you there. Keep in mind that there may be minor differences between cabinets made early and late in production. The information here was taken from a pair of factory 4331's that I had completely gutted for restoration some years back.

I am missing some info on the cabinet back panel drawings so I will try to post it later. Check with SPEAKERDAVE for the length of the port tube since he has a pair. I seem to have lost that info and I don't have a pair anymore to measure the length.

Hope this helps - Rick

[saeman]

Here's a couple more pics. One shows a little closer view of the saddle that supports the 2420 mid driver. It is integral to the rear access cover. I can hopefully post some details of this assembly later. Also there's a pic that shows the internal metal "L" brackets that are provided for support when hanging the enclosure. One is visible in Dave's pics too.

[barkingdog]

Rick,

Thank you. You are truly a gentleman and a scholar.

These are exactly what I was looking for.

Speakerdave? Can you assist with the port length?

Thanks to everyone who helped. All excellent information.

Cheers,
James.

[4313B]

These are exactly what I was looking for.This is exactly the kind of stuff we've been looking for with respect to various JBL systems since the forum first started. :)

Thanks Speakerdave and Rick! :cheers:

[speakerdave]

Speakerdave? Can you assist with the port length?

Post # 8

[speakerdave]

Your frame dimension should be made to work with your actual box (things happen). Mine is 28 3/16 by 21 15/16 measured over the cloth.

The part of the frame that fits against the baffle is cut from one piece of 5/8" particle board; it is cut square on the outer edge.

The depth of the frame is 2 11/16", consisting of the particle board, short corner blocks and intermediate struts, and the outer rails which are made of 1/2" softwood and fastened to the ends of the corner blocks and struts. The bevel of the frame sides is achieved by cutting a 5 degree bevel on the outside lateral surfaces of the corner blocks, intermediate struts and outer rails. There is a cross piece reinforcing the outer rails in the long dimension. It is made of 3/4" solid softwood and fitted to the rails with a lap joint so that it's front surface is held back from the plane of the cloth. It is positioned to fit above the woofer and below the 2308. In addition, there are four small metal L brackets screwed to the outer rails to provide anchors for the tie tacks that mount the long metal badges to the front of the grille cloth, one pair for horizontal and one for vertical orientation.

These photographs may help:

[Hofmannhp]

thanks Dave for your grill pics.....searched for help to this in another thread.

I also try to find out how they fixed the cloth around the corners of the grill frame blocks.
I can not imagine that it is folded there?

HP

[speakerdave]

The cloth is folded around the frame and about 1/2-5/8" on the back. It is folded and lapped at the corner. That is much better than cutting it at that point, I think. The cloth is so light that it does not bunch up significantly at all.

David

[Hofmannhp]

The cloth is folded around the frame and about 1/2-5/8" on the back. It is folded and lapped at the corner. That is much better than cutting it at that point, I think. The cloth is so light that it does not bunch up significantly at all.

David

Thanks David for your comments,
additional question:
can you pls post a pic from the edges/corners how they folded the cloth, and what's the angle of the grill corners from side to front?
Thanks....

HP

[speakerdave]

. . . . additional question:
can you pls post a pic from the edges/corners how they folded the cloth, and what's the angle of the grill corners from side to front?
Thanks....

Right--I didn't quite understand your question. The cloth seems to be a stretch fabric. There is no folding and lapping at the corners except in back. The way the warp and weft run at the corners it does appear that the cloth is stretched over the frame so that at the corners it shrinks back enough to avoid the necessity of folding. Don't know if the Z-Blue material has this same elasticity. I will try to get a closeup, but I will need to use a film camera, and it will take a week or more to get the image up here.

The bevel of the frame is 5 degrees on top, bottom, and the sides. The angle at the corners may look like more from some perspectives, but in fact it is a little less (slightly under 4 degrees).

David

[Hofmannhp]

Hi again,

here's the raw grill construction.....need to be sanded at all corners, painted black and then the Zilch-cloth.

HP

PS: it's a lot more stable then my construction from 1980

[richluvsound]

Hi All,

can anyone tell me the width and length of the 4333a grill. I have and grill from a utility grey pair but, in seems to be about 3/16 short all the way round.

TIA ,Rich

[speakerdave]

Hi All,

can anyone tell me the width and length of the 4333a grill. I have and grill from a utility grey pair but, in seems to be about 3/16 short all the way round.

TIA ,Rich

Measuring over the cloth I have 28-1/4 by 22.

[richluvsound]

Many thanks Dave

Rich

[berlinhifi]

Hi All,

can anyone tell me the width and length of the 4333a grill. I have and grill from a utility grey pair but, in seems to be about 3/16 short all the way round.

TIA ,Rich



rich, someone over here in berlin is getting excited. some 4333 grilles on their way, it seems..... darius
:applaud:

[spirou38]

Hi All,

can anyone tell me the width and length of the 4333a grill. I have and grill from a utility grey pair but, in seems to be about 3/16 short all the way round.

TIA ,Rich

Hi RichLuvSound,

As I don't know how to insert an Excel file, here are some pictures of drawings I made with Excel :

87753

87754

87755

Best regards from France