sub 4645c

[faulken]

Hello,

I'm searching internal plan of 4645c ? I got the 2242h but I would like to make the 4645c. :D

Thanks

[Zilch]

Justa box, looks like:

http://www.jblproservice.com/pdf/Theatre%20Series/4645C.pdf

http://www.jblpro.com/pub/cinema/4645c.pdf

[Don Mascali]

I have two of these and will be happy to provide measurements if needed.

[4313B]

Internal dimensions
External dimensions along with any recesses
Bracing
Port/Duct dimensions
Photos would be nice as well.

Thanks :)

http://audioheritage.csdco.com/vbulletin/showthread.php?t=3166

[Don Mascali]

I'll work it up over the weekend.

[faulken]

I'll work it up over the weekend.

Great great great :thmbsup:

I'm waiting.

Thanks you.

[Don Mascali]

Here are the notes for the cabinets.
I have pics (7mp), but don't have a clue as to how to post themhttp://audioheritage.org/vbulletin/images/smilies/banghead.gif
Perhaps some kind soul will step up?
Please feel free to ask for any further info,
Don



JBL 4645C cabinet dimensions

25 ½” W x 39” H x 17 ½” D

Front and rear baffle are made from 1” MDF

Top, bottom and sides are made from ¾” MDF

Internal brace is ¾” MDF 37 ½” H x 24”W with cutouts and centered front to back

The cutouts are 4” x 17 ¼” and 25” x 17 ½”

This leaves a 3 5/16” thick border around the inside of the box and 2” behind the driver

1” fiberglass behind the driver, on the bottom and lower sides

Above the driver area there is nothing except paint behind the port opening

Front to back stiffener at the top center of the driver cutout is 5 ¼” x 16”

Port ID is 7 1/4”, OD is 7 ½”, tube is 1/8” thick paperboard material

Port length is 12 ½” from front of baffle to end of tube

Tube is rabbeted into baffle 5/8” overall length of paper tube is 12 1/8”

The front and rear baffle boards are set in ½” from the edge of the side boards.




Disclaimer: I know that the spec sheet for these has different dimensions for the box.
BS, I say! I have two off these that were ordered at different times and both share the measurements shown.

[faulken]

Here are the notes for the cabinets.
I have pics (7mp), but don't have a clue as to how to post themhttp://audioheritage.org/vbulletin/images/smilies/banghead.gif
Perhaps some kind soul will step up?
Please feel free to ask for any further info,
Don



JBL 4645C cabinet dimensions

25 ½” W x 39” H x 17 ½” D

Front and rear baffle are made from 1” MDF

Top, bottom and sides are made from ¾” MDF

Internal brace is ¾” MDF 37 ½” H x 24”W with cutouts and centered front to back

The cutouts are 4” x 17 ¼” and 25” x 17 ½”

This leaves a 3 5/16” thick border around the inside of the box and 2” behind the driver

1” fiberglass behind the driver, on the bottom and lower sides

Above the driver area there is nothing except paint behind the port opening

Front to back stiffener at the top center of the driver cutout is 5 ¼” x 16”

Port ID is 7 1/4”, OD is 7 ½”, tube is 1/8” thick paperboard material

Port length is 12 ½” from front of baffle to end of tube

Tube is rabbeted into baffle 5/8” overall length of paper tube is 12 1/8”

The front and rear baffle boards are set in ½” from the edge of the side boards.




Disclaimer: I know that the spec sheet for these has different dimensions for the box.
BS, I say! I have two off these that were ordered at different times and both share the measurements shown.


Hello,

thanks a lot.
For the pics when you submit reply, I got an yellow icon with a moutain in the top. Click on it and you can insert a pic.

+
Nico

[Don Mascali]

There is a limit due to bandwidth and these pics are huge. I don't know how to resize them.

I can E-mail them to you if you like.

They need to be posted to the archive to keep them for future reference.

[faulken]

Look your private message :)

+

[Zilch]

Your photo editor program will have a "Resize" function, most likely. I edit down to 480 x 600 for posting here, after saving the resized pics as separate files so as to retain the originals as well.

See here also: http://audioheritage.org/vbulletin/showthread.php?t=817

[Don Mascali]

Ok

[4313B]

I guess we need just a few more dimensions -

Distance of port from edge
Distance of driver from edge
Distance of input terminal from edge

Thanks!

[Don Mascali]

Ok

[Don Mascali]

The driver and port cutouts are 4 7/8" from the top and bottom edge of the baffle board and centered.

The terminal cup cutout is 7 7/8" from the bottom edge of the baffle board and centered

[Don Mascali]

This is where they sit

[Don Mascali]

This is part of my E-mail to Nico, I felt it might be of interest to some.


I personaly don't pay much attention to the center channel as it just fills in dialog in movies. Same thing with surround and rear. I am not a "Golden Ear" type. I like music loud and clean. Mostly Blues and rock.

"I bought the whole cabinet because the drivers were $600us and I got the systems for $800us. I thought I could just veneer it with the wood of my choice whenever. That way there will be 1 1/2" panels and everything will be stiffer. I have grown to like the black cabinets below the screen. They aren't so noticeable. They don't seem to need equalization due to room gain and the Beringer PEQ-2200 are for room modes and the adjustable low cut. At $60 each I couldn't build any thing cheaper. I run them in stereo 20hz low cut and up to 140hz with the built in amp low pass. The amps are Yamaha P-7000 @ 700w per side and they have never even started the cooling fans."

[Zilch]

From this earlier thread: http://audioheritage.org/vbulletin/showthread.php?t=402, there's options, as well.



If you are going to build your own, the specifications to use are 8.0 cubic feet tuned to 25 Hz. Use 1" thick MDF liberally braced. The internal dimensions I personally use are 29-7/8" x 24" x 19-1/4". This puts the lowest internal standing wave at ~ 225 Hz. You can build your enclosure(s) to model the Synthesis One styling.

[Wonders what port configuration Giskard uses on these bad boys....]

[4313B]

I use dual 6-inch ports.

[faulken]

I would like to know the speaker use in the synthesis sub ? I listen the Hercule system, and my opinion :mad: . I hope it isn't the 2242h.

In the same think I don't like 2245h sound.

When I look the pictures of the internal 4645c, I think that Jbl optimise them box. Make a copy of it, seem to be difficult.

+

[johnaec]

I would like to know the speaker use in the synthesis sub ? I listen the Hercule system, and my opinion :mad: . I hope it isn't the 2242h.

In the same think I don't like 2245h sound.According to the JBL website, the 18" Synthesis S1S-EX 18" sub uses an "Aquaplas" cone - I've never heard of any of the current pro series 18" drivers to be using this. It also has a foam surround. This seems to make it most similar to the 2245H, which has both a foam surround and white damping material, (aquaplas?), sprayed on the back of the cone. The stated frequency response down to 20hz is also similar.

John

[4313B]

Ok, once again. The S1S is basically the Consumer version of the 4645. The S1S and 4645 originally used the 2245H. At that time enclosure tunings were 30 Hz. JBL later changed to the 2242H and retuned the enclosures to 25 Hz.

"When I look the pictures of the internal 4645c, I think that Jbl optimise them box. Make a copy of it, seem to be difficult."

I disagree.


According to the JBL website, the 18" Synthesis S1S-EX 18" sub uses an "Aquaplas" cone - I've never heard of any of the current pro series 18" drivers to be using this. It also has a foam surround. This seems to make it most similar to the 2245H, which has both a foam surround and white damping material, (aquaplas?), sprayed on the back of the cone. The stated frequency response down to 20hz is also similar.

John2242HPL - Originally it was the 2245H.

[johnaec]

2242HPL - Originally it was the 2245H.So does the HPL version of the 2242 have the foam surround as pictured at the JBL website, or is the pic outdated?

John

[4313B]

This is a picture of a 2245H in an S1S enclosure -

[4313B]

This is a picture of the S1S with the 2242HPL -

[4313B]

Old and new...

2245H and 2242H

[johnaec]

This is a picture of the S1S with the 2242HPL -'Hard to tell on my monitor - is that a foam surround on the 2242HPL? Is the rest of the speaker the same as the 2242H, (magnet assembly, voice coil, etc.)? I notice the Fs of the standard 2242H is way up at 35hz.

That wall of sound would fill one my walls just right! :p

John

[faulken]

If the 2242h and the 2242hpl are different, I understand why I prefer 4645c :D



+

[4313B]

The 2245H had the foam surround and aquaplas on the back of the cone.

[4313B]

If the 2242h and the 2242hpl are different, I understand why I prefer 4645c :D



+The 2242H and 2242HPL are the same except for the rubber tire. The 2242HPL lacks the rubber tire around the magnet disc. You can buy the rubber tire from parts for $40 if you want a 2242H.

[Zilch]

Unless there's something I don't understand, there's no magic in this. If you want a shorter, deeper box, you build according to Giskard's dimensions. Otherwise, use those of the 4645. In either case, you'll want to use heavy material and massive bracing. For more alternatives, and construction suggestions, check out this article from the library: http://www.lansingheritage.org/html/jbl/reference/technical/1983-subs.htm.

Either driver (2245 or 2242) will work an any of the boxes. The JBL Tech Note says 2242 replaces 2245. They have done so in their product offerings, so I take them at their word. Both require EQ to reach 20 Hz. BUT, it doesn't matter. In home use, room response augments the low end to obviate the necessity of EQ.

You want more, build 2 or 4 of them, and mutual coupling will push the response further down there as well. JBL recommends using arrays of 8. :applaud:

[Don Mascali]

http://www.lansingheritage.org/html/jbl/reference/technical/1983-subs.htm

That is thesame article that I used to design my B-380 clones. They are great speakers, I just needed more eficiency to match up with the others. Doubling up with the 4645Cs does a fine job.

[4313B]

Agreed Zilch and Don :yes:

[JBL 4645]

This is part of my E-mail to Nico, I felt it might be of interest to some.


I personaly don't pay much attention to the center channel as it just fills in dialog in movies. Same thing with surround and rear. I am not a "Golden Ear" type. I like music loud and clean. Mostly Blues and rock.

"I bought the whole cabinet because the drivers were $600us and I got the systems for $800us. I thought I could just veneer it with the wood of my choice whenever. That way there will be 1 1/2" panels and everything will be stiffer. I have grown to like the black cabinets below the screen. They aren't so noticeable. They don't seem to need equalization due to room gain and the Beringer PEQ-2200 are for room modes and the adjustable low cut. At $60 each I couldn't build any thing cheaper. I run them in stereo 20hz low cut and up to 140hz with the built in amp low pass. The amps are Yamaha P-7000 @ 700w per side and they have never even started the cooling fans."

http://audioheritage.org/vbulletin/attachment.php?attachmentid=4553&stc=1&d=1105212551

Don

That’s the same JBL 4645C that’s used at the Empire Leicester square only they use x16 of them with a staggering 20KW alone for the LFE.1.:p:D

[lm324]

JBL 4645C cabinet dimensions

25 ½” W x 39” H x 17 ½” D

Front and rear baffle are made from 1” MDF

Front to back stiffener at the top center of the driver cutout is 5 ¼” x 16”[/quote]


I have a question: D= 17 1/2", front= 1" and rear= 1"

As can be the measure? Front to back stiffener 16" .

Thanks.

Roger

[neils]

First off, Dan thanks so much for posting the dimensions for the 4645C cabinet. Usually when you build a speaker box, you run down to your electronic parts store to purchase a pre-made port or run to your hardware store to pick up some raw PVC pipe to turn into a port. Only issue with this is that pre-made ports are usually in the 2-4" range, and PVC pipe probably up to 6".

Where the heck would I be able to find a very precise 7-1/8" paper or PVC port, used in the 4645C??

I plan on building this cabinet, but am lost where to find such a big and specific size port. Any help would be greatly appreciated.

Please toss me an email as I am not always on this forum: [email protected]

Thanks so much for your time !!!

Neil

[Eaulive]

Yup, I'm building one also so I will need to source that somehow.
We can get close like with 6" or 8" and change the port length accordingly, but I still would like the real deal :D

[Eaulive]

JBL 4645C cabinet dimensions

25 ½” W x 39” H x 17 ½” D

Front and rear baffle are made from 1” MDF

Front to back stiffener at the top center of the driver cutout is 5 ¼” x 16”


I have a question: D= 17 1/2", front= 1" and rear= 1"

As can be the measure? Front to back stiffener 16" .

Thanks.

Roger[/QUOTE]

Now that I'm drawing the plan I end up with the same doubt. If the box is 17½" deep and the baffle and back are 1" thick and recessed by ½", how can the center brace be 16" long ?
Did you measure it or you just assumed? I guess it's more like 14½" no?

[Don Mascali]

I just measured it and it is 15" deep inside.

There is a company that makes concrete forms called Sonotube. It can be purchased in 8".

PVC pipe can be found in 8" also.
http://www.mcmaster.com/#pvc-(schedule-40)-pipe/=f84nyj (http://www.mcmaster.com/#pvc-%28schedule-40%29-pipe/=f84nyj) @$59.41 for a 5' length.

[Eaulive]

I just measured it and it is 15" deep inside.

Hi Don.
Still doesn't add up, maybe then the front and back recess is only ¼" ? :dont-know:


I was trying to get the measures as close possible to the original so I didn't have to tune the box, but now since the port size will change, I will have to retune it anyways so ½" difference in depth won't kill me :D

[JBL FOREVER]

I just measured it and it is 15" deep inside.

There is a company that makes concrete forms called Sonotube. It can be purchased in 8".

PVC pipe can be found in 8" also.
http://www.mcmaster.com/#pvc-(schedule-40)-pipe/=f84nyj (http://www.mcmaster.com/#pvc-%28schedule-40%29-pipe/=f84nyj) @$59.41 for a 5' length.


Hi Don,

Sorry to disturb you with this but like EauVive from Montreal, I'm going to start to build two 4645C based on your given dimensions, I've found a carton tube manufacturer that will make an exact copy of tube, thus I will not need to retune the box but I'm still struggling with this 1/2 inch depth error on the box as previously mentionned, if I take your dimensions the inside depth is 14 1/2 inch and not 15, could you please confirm which dimension I need to use to get an exact copy of the 4645C?

Thanks

[Don Mascali]

OK I found the problem;

The actual overall depth is 17 3/4". I don't know where this measurement went wrong but this is the mistake.
The inset on the front and back 1" boards is 7/16". 15" inside from front to back between the boards.

7/16" |-- 1" -- |----------- 15" -------------|-- 1" -- | 7/16"

Sorry about the mix up.:crying:

[Eaulive]

OK I found the problem;

The actual overall depth is 17 3/4". I don't know where this measurement went wrong but this is the mistake.
The inset on the front and back 1" boards is 7/16". 15" inside from front to back between the boards.

7/16" |-- 1" -- |----------- 15" -------------|-- 1" -- | 7/16"

Sorry about the mix up.:crying:

I still have a 1/8th of an inch discrepancy, but that's close enough :D

[Eaulive]

OK I found the problem;

The actual overall depth is 17 3/4". I don't know where this measurement went wrong but this is the mistake.
The inset on the front and back 1" boards is 7/16". 15" inside from front to back between the boards.

7/16" |-- 1" -- |----------- 15" -------------|-- 1" -- | 7/16"

Sorry about the mix up.:crying:

And by the way Don, the measurements you have (39 x 25½ x 17¾) concurr with the JBL spec sheet for the 4641.

http://www.jblproservice.com/pdf/Theatre%20Series/4641.pdf

According to JBL, the 4645B/C measures 39¾ x 26½ x 17¾ and the original 4645 is 39¾ x 26½ x 17¼

The 4645C and the 4641 are quite similar, but they use 2242 and 2241 respectively, I don't know what to think about all this.

Anyways, I want to build 4641s since I have 2241 woofers so problem solved :D

[Don Mascali]

Where is the discrepancy? (15+1+1=17" and 7/16"+7/16"=3/4") It seems to add up to 17 3/4".

[maxwedge]

Where is the discrepancy? (15+1+1=17" and 7/16"+7/16"=3/4") It seems to add up to 17 3/4".

7/16+7/16=7/8??http://www.audioheritage.org/vbulletin/images/smilies/dont-know.gifhttp://www.audioheritage.org/vbulletin/images/smilies/tongue.gif

[Don Mascali]

I guess that's why I failed 6th grade math...:eek:

[maxwedge]

It's alright, outside looking in is always easier.:D

[Eaulive]

And if some day we could get rid of those fractions and get on the SI bandwagon it would be even simplier :p

[maxwedge]

Don't know what SI means but every thing I do at work is measured in metric but I cut wood in inches.:p

[Eaulive]

After a year, we finally started the 4641 project, My friend and me.
Thanks to Don who graciously took the time to take apart his cabinets in order to provide the dimensions and details needed.
We are not cabinet makers and we had the 1" and ¾" sheets cut at the local hardware store, the port is an 8" sonotube which fortunately does not have 8" ID but about 7"3/8, so pretty close.

Pictures are here, they are from last weekend, we should finalize the project and listen to it this sunday :bouncy:

http://www.flickr.com/photos/eaulive/sets/72157632495521211/

[Lee in Montreal]

Nice. Did you buy the pair of 2241s of Kijiji Montreal last week? ;-)

[Titanium Dome]

That looks like so much fun! I hope you enjoy the results as much as the effort. :)

[Eaulive]

Nice. Did you buy the pair of 2241s of Kijiji Montreal last week? ;-)

Nope, it's a pair I got from subwoof a year ago...
I think a friend of Stéphane grabbed the ones on Kijiji

[hlaari]

It would be nice to see how 2269 will work in 4645C enclosure
I think at 2269 will be better than both 2245 and 2242

have someone try 2269 in similar enclosure like 4645C

[Ed Zeppeli]

Hi all,

I plan on building a 4645c replica for a 2242H I picked up yesterday. My twist is that rather than front firing I'd like it to be down-firing.

Rather than start a new thread I thought I'd just add to this informative one.

Any special considerations for this alteration? Minimum distance from floor for cone and/or port? Is the suspension stiff enough to handle it? ( probably)

Thanks very much,
Warren