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View Full Version : JBL-NOT!! - DIY 4351 Studio Monitor



saeman
07-26-2005, 06:56 PM
For some of you guys that have been following my current project, here's an update on my new 4351 Studio Monitor. Had to call it something. The project grew out of lack of acceptable space for my 4350's. They're currently sitting next to my big screen with a mere 1/2" gap between wall/speaker/TV/speaker/wall. Am affraid at full tilt that they might degause my TV???

Since JBL never found their way clear to make a verticle version of the 4350 I decided to give it a try. They take up less floor space than my Sovereigns and when the second cabinet is done, they'll sit on either side of the big screen with noticeable space left over. They kinda look like 4345's on steroids but the cabinet dimensions are identical to the horizontal sitting 4350. Since the baffle arrangement of the 4350 does not lend itself to placing them upright I had to come up with another idea. The jury is out right now as to how they will sound. Will keep you all posted.

The high freq drivers are up higher in these cabinets and should help solve a common complaint of the 4350 in home environments. Although my wife has never complained about my 4350's she will surely notice the difference when they're both in place. These are as close to livingroom friendly 4350's as you can get. For you guys that are thinking of building 4350's, you might give some thought of going higher instead of wider. More later when I get them both done and grilles made - any news on the blue cloth??? Regards - Rick

Zilch
07-26-2005, 07:02 PM
Any news on the blue cloth???Hi, Rick.

No word yet. Time for me to call and "expedite," probably.... ;)

[Gonna take plenty to cover the fronts of THOSE beauties!]

saeman
07-26-2005, 07:28 PM
Hi Zilch: Thanx for the update. I figured there was some delay but I didn't want to bug you. I will still commit to buying one BFC (big freakin chunk), 30 yards, when it comes along. Regards - Rick

johnaec
07-26-2005, 07:33 PM
Wow! :applaud:

John

boputnam
07-26-2005, 07:50 PM
Holy shit! A 4345 Wanna Be... :rotfl:

But we've had the debate before - my memory is VERY clear on one 2245H toasting two measly 2235's.... ;)

Just kidding - that is a really cool idea. Incredible design, actually. Wonderful attention to a mere re-orientation of orginal. I think this might be one of the coolest DIY'ers, ever. No kidding.

pelly3s
07-26-2005, 07:58 PM
those look beautiful. I wish I had a pair

saeman
07-26-2005, 08:17 PM
Thanx Bo: You're surely right on the 2245H, it's a serious driver and I don't currently own anything using them. I did have some surplus 4350 components though and that's what got this project going. That and the fact that I love making big wood into little wood and then making it back into big wood. After finishing my rosewood 4350B's I needed a project. Made a mess out of the garage for a few weeks putting this one together. I came up with the idea and couldn't leave it alone.

I've got some pics of the internals but can't find them right now. Will post them when they surface. Baffles are left/right mirror immaged like the 4344/4345. Baffle and all sides are 1" stock, more like the 4355 than the 4350. Empty cabinets weigh about 180 lbs. My son and I nearly killed out selves bringing the empty cab down the stairs. Put the components in afterwards.

Currently populated with 2231A'a, 2202H, 2440, 2405. 3107. I'd like to end up with 2235H's and 2441's with modified x-overs but need to correct my neg cash flow. Am spent out on all of my big monitor projects. Will give them a real good A/B comparison to my 4350's and decide which ones to keep. Sitting next to the 4350's they seem huge. Will have to get used to them and keep remembering that they take up 15" less floor space.

saeman
07-26-2005, 08:32 PM
those look beautiful. I wish I had a pair

Jump in there and start cutting the wood. I'll give you all of my plans. The total materials cost was a bit under $400. That and a bunch of hours and you're into a pair of nice cabinets. No exotic tools needed, just patience. I have a shop area where I normally do all of my woodworking, but it's in the upstairs loft of an industrial building, and it's impossible to work there in the heat with no A/C (John P. - you know what I'm talking about - you're seen my shop). Built this cabinet in my garage at home on a pair of saw horses with a piece of plywood layed over them. Took some extra time not having the extras but it came out ok. Besides a screwdriver, drill, sander and some clamps the whole cabinet was built with a skill saw and a router (true). Forgot about using my wife's clothes iron to lay down the veneer!!!

Ken Pachkowsky
07-26-2005, 10:26 PM
A job well done. Would love to hear them.

Congrats on the design. It appears well thought out. Keep us updated with your performance views.

Very nice indeed:applaud:

Ken

Mr. Widget
07-26-2005, 10:36 PM
Since JBL never found their way clear to make a verticle version of the 4350 I decided to give it a try. They take up less floor space than my Sovereigns and when the second cabinet is done, they'll sit on either side of the big screen with noticeable space left over. They kinda look like 4345's on steroids but the cabinet dimensions are identical to the horizontal sitting 4350. Since the baffle arrangement of the 4350 does not lend itself to placing them upright I had to come up with another idea.

Nice work!

You've obviously come to a point where you know the sound you like... :applaud:

If I were going the 43XX+ route I think I'd go with a 4345 but swap out the 2421 with a 2441 and a Westlake horn... just my take on it. As for tower configurations, this is what Westlake did. It is a real monster with dual 18" woofers!

Widget

Ken Pachkowsky
07-26-2005, 10:52 PM
Nice work!

You've obviously come to a point where you know the sound you like... :applaud:

If I were going the 43XX+ route I think I'd go with a 4345 but swap out the 2421 with a 2441 and a Westlake horn... just my take on it. As for tower configurations, this is what Westlake did. It is a real monster with dual 18" woofers!

Widget

The one thing you forgot about the Tower SM1's was the 110K+ price tag. By the way the MRX-2 and HR-X active crossovers are about 25K extra. Hmm now what 5 amps should we use to drive them?

One can dream though:)

Ken

Mr. Widget
07-26-2005, 10:59 PM
One can dream though:)


I would call it more of a nightmare! The damn thing is 6' tall and weighs 950lbs!

I just pointed it out as a different vertical option... I certainly wasn't advocating that direction. I do like the significantly more tame 4345s however.;)

Widget

Titanium Dome
07-27-2005, 01:28 AM
Looks terrific. Well done.

On the mirror-imaged twin did you simply take an identical baffle and turn it 180 degrees when you installed it?

Guido
07-27-2005, 03:43 AM
Gorgeous! :applaud:

yggdrasil
07-27-2005, 03:51 AM
Beuatiful Rick.:applaud:

Tom Loizeaux
07-27-2005, 05:07 AM
Those look great!
I had the same thoughts on the 4350...why didn't JBL ever make a tall version...and, if I were to get 4350s, I would want to make new vertical cabinets for them. You did it!
(I assume the other vertical is a mirror image of the one shown)

One reason I went for the 4343s was that they were able to be set up in the vertical position. I love them to death, but I suspect a second 15", and changing to a 2" throat driver, and a 12" mid (to match the larger driver), could only improve on the 4343.
Since you're bi-amping these, you could use an upgraded crossover for the 4345 (from Ian) and make these "state of the art"!
Congratulations!

Tom

Lancer
07-27-2005, 05:31 AM
Since you're bi-amping these, you could use an upgraded crossover for the 4345 (from Ian) and make these "state of the art"!Use the 4355 network.

Ian Mackenzie
07-27-2005, 06:07 AM
I recall there is a new equivalent of the 4355 crossover somewhere.

Ian

Tom Loizeaux
07-27-2005, 06:52 AM
Hey, you guys are right!
With the 12" and 2" throat compression driver, you'll need, not a crossover for the 4344, but a crossover that is optimized for the 4350/4355 componants.

Sorry, my mistake.

Tom

Robh3606
07-27-2005, 07:20 AM
Well those are nice!!
Curious to see what you think compared to the stock 4350. You did a great job!

Rob:applaud:

Regis
07-27-2005, 08:07 AM
Very nice work Rick! Amazing what you pulled off with the simple tools you had. The results look like you had a whole woodshop at your disposal. Looking forward to the A/B comparison. I'd almost be willing to bet that you'll like the vertical format better, as the midrange and the horn is higher up vs. the lower position of the horizontal position. Congrats on a job well done! :D

Alex Lancaster
07-27-2005, 08:18 AM
:applaud: They look really good; How do they sound?, just Your opinion, no fancy testing.

saeman
07-27-2005, 09:14 AM
Very nice work Rick! Amazing what you pulled off with the simple tools you had.

I cheated a bit as I did use my table saw and joiner at my shop to cut the face trim and internal braces. But - to all interested in taking on a project like this - don't let the lack of fancy tools scare you off.


I'd almost be willing to bet that you'll like the vertical format better, as the midrange and the horn is higher up vs. the lower position of the horizontal position. Congrats on a job well done! :D

I'm betting they will sound better. My first JBL's (1974) were my Sovereigns and I always thought they were great sounding. One day a few years ago I got the bug to put the S8R system into a vertical configuration. I built two tall towers with the same internal volume as the sovs and populated them with varying components (S7R, S8R, etc.). Getting the 075 and 375 up off the floor created a totally different sound stage. JBL was certainly aware of the problem as the Sovereign and Olympus baffles are slanted back. Just not enough to make the difference. Getting the mid/high components up to ear level made a big difference. Thanx for your comments. Rick

saeman
07-27-2005, 09:17 AM
:applaud: They look really good; How do they sound?, just Your opinion, no fancy testing.

The second cabinet is still in pieces but I'll soon start working on it and will let you know when I have a finished pair.

saeman
07-27-2005, 09:38 AM
Those look great!
I had the same thoughts on the 4350...why didn't JBL ever make a tall version...and, if I were to get 4350s, I would want to make new vertical cabinets for them. You did it!
(I assume the other vertical is a mirror image of the one shown)

One reason I went for the 4343s was that they were able to be set up in the vertical position. I love them to death, but I suspect a second 15", and changing to a 2" throat driver, and a 12" mid (to match the larger driver), could only improve on the 4343.
Since you're bi-amping these, you could use an upgraded crossover for the 4345 (from Ian) and make these "state of the art"!
Congratulations!

Tom

Hi Tom and thanx for your comments. I hope to make some improvements in these monitors as time goes on. I spoke to Giskard some time back about building custom 4355 x-overs with these speakers in mind. Now that they're coming to life I will start to rethink that goal. I hope to end up with 2235H's in them along with 2441's and tailor the x-overs accordingly. I'm with you on the 4343's. I loved mine too but had an opportunity some time back to pick up a mint pair of 4350's. I unfortunately had to let my 4343's go to fund the new ones; Tough choice. If we were to keep all the toys we ever owned, we'de have no place to sleep and if we did, we'de be sleeping alone.
Rick http://audioheritage.org/vbulletin/images/smilies/smile.gif P.S. How about 6 channel 4350 Surround ?? How's that for a sick thought ?? My wife would no doubt say I've gone too far.

Mr. Widget
07-27-2005, 09:56 AM
Tough choice. If we were to keep all the toys we ever owned, we'd have no place to sleep and if we did, we'd be sleeping alone.:rotfl:

So true!

Are these using original 4350 dimensions so they are approximately 48" tall?
How far from the floor is the center of the 2202?

Widget

saeman
07-27-2005, 09:57 AM
Nice work!

You've obviously come to a point where you know the sound you like... :applaud:



Wig: Thanx for your "very correct" statement. I am in my own groove for sure with my JBL's, big horn loaded enclosures. I got into this groove over 30 years ago and have just stayed there. What scares me about my association with this forum is all of the other systems and options that are being discussed regularly. I'd be in real big trouble if I deviated off into some of these big $$$ exotic systems. My JBL's have kept me happy and so far I've not gone over to "The Dark Side". I did once own a big pair of Polk reference series towers. All they did was suck the life out of my 250 wpc mac power amp.

Mr. Widget
07-27-2005, 10:07 AM
I'd be in real big trouble if I deviated off into some of these big $$$ exotic systems.

Bigger??? More exotic???

You are already deep in the trouble zone! Keep it up!;)

Widget

saeman
07-27-2005, 10:14 AM
Found some pics of the cabinet under construction. Although the end result looks good, one of my primary goals with these monitors was to have a finished baffle, kinda like the Westies. Something that looked real nice when the grilles were off. I decided to have an oak baffle finished in blue stain and satin polyeurethane. That way all of the grain would be highlighted, instead of the traditional JBL blue paint.

I intended to veneer either baltic birch or particle board in oak veneer. Was about to do that when I found some 1" oak plywood. Plywood would not be my first choice but since it was 1" thick and I braced it to the hilt I suspect there will be no problem. Anyway, I went to all this effort and then had no end of problems getting an even stain coverage on the baffle. Spots and irregularities everywhere. I finally gave up and painted it blue. BIG dissappointment since the stained blue baffle was a major goal. Will try again when I build the second cabinet. If I pull it off I'll take on the nasty job of stripping the blue paint on the first baffle.

saeman
07-27-2005, 10:22 AM
A couple more pics

saeman
07-27-2005, 10:24 AM
More pics

saeman
07-27-2005, 10:35 AM
:rotfl:

So true!

Are these using original 4350 dimensions so they are approximately 48" tall?
How far from the floor is the center of the 2202?

Widget

The center of the 2202 is about 37" off the floor. Original 4350 is 47 5/8" wide by 33" tall sitting on a base about 2" tall. These cabs are 48" tall on top of a 2" base and are 33" wide (dimensions of the 4355 cabinet).

Mr. Widget
07-27-2005, 10:40 AM
The center of the 2202 is about 37" off the floor.

That should work well. If you have well matched drivers and have the network set up properly, I would expect your vertical alignment to sound quite good.

Widget

Titanium Dome
07-27-2005, 10:49 AM
Found some pics of the cabinet under construction. Although the end result looks good, one of my primary goals with these monitors was to have a finished baffle, kinda like the Westies. Something that looked real nice when the grilles were off. I decided to have an oak baffle finished in blue stain and satin polyeurethane. That way all of the grain would be highlighted, instead of the traditional JBL blue paint.

I intended to veneer either baltic birch or particle board in oak veneer. Was about to do that when I found some 1" oak plywood. Plywood would not be my first choice but since it was 1" thick and I braced it to the hilt I suspect there will be no problem. Anyway, I went to all this effort and then had no end of problems getting an even stain coverage on the baffle. Spots and irregularities everywhere. I finally gave up and painted it blue. BIG dissappointment since the stained blue baffle was a major goal. Will try again when I build the second cabinet. If I pull it off I'll take on the nasty job of stripping the blue paint on the first baffle.

Even though oak is a hardwood, treat it as a softwood when it's a plywood veneer. The thinness, the shaving process, and the bonding process all serve to open up and crush the grain in spots, and also to distort it microsopically. This can result in blotchiness and a sort of cloudiness in places when it is stained.

To minimize this, use a traditional softwood sealer, which will have two effects: 1) to prevent excessive stain penetration into the porous areas created by the veneering process described above, and 2) to lighten the overall cast of the stain, since all the pores will be less receptive. You offset #2 by using a slightly darker stain if need be.

You've got some big scrap that you can experiment on to perfect your system. Read the softwood sealer directions carefully to see how you can vary its effects. I have used this method successfully many, many times on hardwood plywood that otherwise would have looked unsatisfactory. :thmbsup:

Good luck.

Titanium Dome
07-27-2005, 10:55 AM
BTW your design goal with the stained baffles is a great idea and will be very sharp if successful. It will exceed anything JBL could produce for mass distribution and lend an air of class that no one else will have. :yes:

saeman
07-27-2005, 10:56 AM
That should work well. If you have well matched drivers and have the network set up properly, I would expect your vertical alignment to sound quite good.

Widget

Wig: Right now I have four 2231A's with new cone kits in them, two 2202H's, two 2440's with new JBL diaphragms, a mint pair of 2405's and a pair of NOS 3107's. This was my surplus stash and if I ebayed it I wouldn't see it again. To my ears the 2235H is a superior woof to the 2231A so now I go on the hunt for a quad set to replace the 2231A's. Since the 2441 has a better high end than does the 2440 I want to make that change too. In the 4355, what is the x-over point between the 2441 and the 2405?? After talking with Giskard I'm convinced that the x-overs will be the climax of the project. Thanx - Rick

Mr. Widget
07-27-2005, 11:02 AM
In the 4355, what is the x-over point between the 2441 and the 2405??
The crossover is at 10KHz which is similar to the 4350, but it is not at all similar to the 4350... it is a 3rd order network and is a significant step up over the 3107.

Keep going you will have a system that is superior to those 4350Bs!

Widget

saeman
07-27-2005, 11:03 AM
Even though oak is a hardwood, treat it as a softwood when it's a plywood veneer. The thinness, the shaving process, and the bonding process all serve to open up and crush the grain in spots, and also to distort it microsopically. This can result in blotchiness and a sort of cloudiness in places when it is stained.

To minimize this, use a traditional softwood sealer, which will have two effects: 1) to prevent excessive stain penetration into the porous areas created by the veneering process described above, and 2) to lighten the overall cast of the stain, since all the pores will be less receptive. You offset #2 by using a slightly darker stain if need be.

You've got some big scrap that you can experiment on to perfect your system. Read the softwood sealer directions carefully to see how you can vary its effects. I have used this method successfully many, many times on hardwood plywood that otherwise would have looked unsatisfactory. :thmbsup:

Good luck.

Thanx for the advise. Will keep trying. I used a cutout from one of the woofer holes and thought I had it right. I have never used water based stains before so this was a pilot effort for me. I asked about using a sealer ahead of the stain and they told me it wasn't necessary on hardwoods, but I can see from my failed efforts that they may not have been right. I hope to whip this problem as I would really like to end up with a stained blue baffle. Until then I'll have only achieved half of my intended goal. Regards - Rick

boputnam
07-27-2005, 06:26 PM
I got nuthin' new to add here, I just want it known that I am leering at your project. Very, very impressive, man.

I am floored with the attention to authentic detail, engineering and transducer assemblage.

Really well done, Rick! :thmbsup:

saeman
07-27-2005, 07:08 PM
Here's a couple more pics. The second cabinet shell is sitting together dry just to check fit-up and square. Have a little trimming to do and will then start putting in the rest of the braces and the mid-base box. The other pics show the mirror imaged baffles after I had them done.

Ian Mackenzie
07-27-2005, 09:00 PM
I got nuthin' new to add here,
:thmbsup:


Affirmative Will Robinson,


Just send him a tape measure you Dang Yankee...:rotfl:

Ken Pachkowsky
07-27-2005, 11:29 PM
Riessen, may I suggest you try a pair of Widgets wood horns on those new boxes (if the cabs are deep enough). Trust me, you will never go back to that short stubby JBL horn again. The 375's/2441's will smoooooooth out and won't be anywhere near as harsh. I know cause my 4350's had the same stubby horn (I forget the model number)and when I switched out to the longer horn with serpintine lens (same horn lens on the hartsfield) it was an amazing improvement.

Ken

Lancer
07-28-2005, 09:17 AM
That's a slippery slope...

saeman
07-28-2005, 10:19 AM
Riessen, may I suggest you try a pair of Widgets wood horns on those new boxes (if the cabs are deep enough). Trust me, you will never go back to that short stubby JBL horn again. The 375's/2441's will smoooooooth out and won't be anywhere near as harsh. I know cause my 4350's had the same stubby horn (I forget the model number)and when I switched out to the longer horn with serpintine lens (same horn lens on the hartsfield) it was an amazing improvement.

Ken

Hi Ken: I've given some thought to breaking from my old habits on horns. I've thought about the smaller wood horns like some of the Westies use and also about bigger serpentine lenses. I have no experience with either and need some education before deciding what to try. These cabs "are what they are" with little ability to make changes without butchering the baffle. Inside cabinet depth is 15 1/4". Normal 4350 depth is 15 7/16" but I gave up 1/4" when I went to a 1" baffle. When these are complete I need to give my 4341's an overhaul. After that I want to start a new project, something less traditional. I'm sure I'll stick with JBL for my main drivers as I have no interest in TAD, etc. I am interested in learning more about some of the horn/lens options that will improve the high end. Will also look at improving the x-overs. I appreciate your comments and any suggestions in the future. Thanx - Rick

Ken Pachkowsky
07-28-2005, 10:21 AM
That's a slippery slope...

After looking at the photo's again, your right. The baffle does not have enough room where the horn hole is cut.

Ken

speakerdave
07-28-2005, 10:25 AM
That's a slippery slope...

Do you mean as in G.T. recommending against using a 1200 Hz crossover from a baffle mounted driver into a larger horn (for Project May)--the time alignment problems become audible at that frequency?

David

saeman
07-28-2005, 10:33 AM
After looking at the photo's again, your right. The baffle does not have enough room where the horn hole is cut.

Ken

Ken: If you get a chance, show me a pic of what you're talking about. Even though I'm neck deep in big monitors, I always look forward to building something new. I plan to keep these for a while but have had a couple of interested buyers. Since I only "REALISTICALLY" have room in the house for one pair this big something will eventually go. Rick http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

Mr. Widget
07-28-2005, 10:43 AM
Ken: If you get a chance, show me a pic of what you're talking about.
I am not exactly sure where Ken was going with this... but I did spend quite a bit of time messing around in these waters. Here are my explorations. I started with the test boxes in the lower right and ended with the system at the top of the page. Aesthetically I never fell in love with any of them.

As I mentioned earlier... I think you have found your sound... back when I was messing around with 4355s I never found mine. I kept looking and have since stumbled upon it.

Widget

Ken Pachkowsky
07-28-2005, 11:06 AM
Ken: If you get a chance, show me a pic of what you're talking about. Even though I'm neck deep in big monitors, I always look forward to building something new. I plan to keep these for a while but have had a couple of interested buyers. Since I only "REALISTICALLY" have room in the house for one pair this big something will eventually go. Rick http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

Well, I don't have a picture of exactly what I meant but I see Widget has provided several drawings. I know one thing, once you hear the difference between the standard 4350 horn and a wood horn, I would bet you will never look back. The ideal scenario would be loading the horn right on the baffle. I can see from the photos that would not be possible with the current baffle layout.

Ken

saeman
07-28-2005, 11:18 AM
Well, I don't have a picture of exactly what I meant but I see Widget has provided several drawings. I know one thing, once you hear the difference between the standard 4350 horn and a wood horn, I would bet you will never look back. The ideal scenario would be loading the horn right on the baffle. I can see from the photos that would not be possible with the current baffle layout.

Ken

Ken: Is it acceptable to mount the horn TOP/CENTER on the baffle with the 2405 and the mid-base below it, to the right and left of the baffle centerline ??? Looking at Widget's drawings-there's a ton of possibilities. If I build new cabinets they need to be upright for the sake of floor space.

http://audioheritage.org/vbulletin/images/smilies/smile.gif Rick

Lancer
07-28-2005, 11:51 AM
If I build new cabinets they need to be upright for the sake of floor space.Go completely modular then. Use 2234H's instead of 2235H's. The 4435 bottom end is excellent. Use the wood horn as Ken suggests. Put a titanium/aquaplas diaphragm in the 2" throat compression driver. Power the whole mess with active filters. Use a chip amp on the slot loaded ring radiator.

If you do use passive filters don't waste your time with anything less than full blown charge coupled versions of the 4355 filters.

saeman
07-28-2005, 12:57 PM
Guys - Thanks for the input. You have to keep in mind that I'm a plug-n-play JBL guy and I have ZERO experience with some of the off the wall stuff that's out there. Wood Horns - yep, I've seen them and know what they are but never used them. Charge Coupled Capacitors - those are used in Ray Guns, right ??? I'm all for trying something new but if you guys lead me in, you may be stuck baby sitting me thru the project.

How much room on the baffle (L x W) do these wood horns occupy?? Where can I find dimensions on different models?? What cabinet depth is required with a typical 2" throat driver hanging on it?? I would suspect that some sort of internal support is required for the driver. I have planned on building another big system but have not given much thought to WHAT. I guess I'm in the planning stage now. Thanx for your input.

saeman
07-28-2005, 01:36 PM
Cabinet Insulation - Who's the Guru out there that is all knowing on the requirements for insulating the inside surfaces of the cabinets? Why did JBL choose a medium density insulation that is usually about 1" thick? Is denser better? How thick should it be? All that is typically available is regular old house insulation from Home Depot - too soft, no stability, pain in the ass. I recently started using a much higher density fiberglass type that is used by HVAC contractors to insulate ducting. Great to work with, varying thickness available and holds it's form. I used this type on my new cabinets. Will try to get some pics to show it installed. Your comments would be appreciated.

Mr. Widget
07-28-2005, 01:46 PM
I use this stuff... I hate working with it, but love the results... I believe it is identical to the original JBL material.

http://www.audioheritage.org/vbulletin/showpost.php?p=35394&postcount=7

Widget

stevem
07-28-2005, 03:10 PM
The Wrap-on is what I use, but I have been doubling it up for 2 inch thickness in woofer cabinets. Is this a good or bad thing?

edgewound
07-28-2005, 03:13 PM
The Wrap-on is what I use, but I have been doubling it up for 2 inch thickness in woofer cabinets. Is this a good or bad thing?

If it sounds good....it is indeed a good thing;) ...when in doubt..trust your ears... because you can't use anyone elses'.:)

Edgewound

Mr. Widget
07-28-2005, 03:53 PM
Yeah, ....what he said.:blah:


Widget

Ken Pachkowsky
07-28-2005, 07:21 PM
Riessen

The horn would work great mounted right on top and in the center of the cab but the WAF may cause you probs. Thats "wife acceptance factor".

Be aware, these are damned expensive horns and you may not have it in the budget? They are however built better than the original Westlake horns in MHO.

In the words of Mike Myers " They be smooth "like Butta".

PS: There was a guy on Ebay selling a beat up pair of old Westlakes that had the large wood horn just last week. I don't know if they sold but you could spend 20-30 hours repairing and refinishing them and save a bundle. Bummer, they sold http://cgi.ebay.com/Westlake-Hiddley-Monitors-Pair_W0QQitemZ7337818436QQcategoryZ47093QQrdZ1QQcm dZViewItem

At 200.00 they were a steal even in that bad a shape. Mine took some work to clean up as well.

In any case you have great looking speaker there. Please let us know how you like them.

Ken


Ken

saeman
07-28-2005, 08:29 PM
Ken: I've thought about some of the Westies and may well coast into a pair some day.

I think I'd prefer the horn mounted on the baffle and keep everything under the grille. Westlake has a similar sized vertical 4 way and 5 way with baffle mounted horn. If the price of the wood horns changes my mind I'll look into a longer metal horn with a serpentine lens. Who makes a suitable horn/with serp lens for the 2" throat drivers??

Guess I should keep an eye open for a pair of Westlakes that are beat and need work. I'd not hesitate to take on the restoration.

Thanx again - Rick

John
07-29-2005, 12:24 AM
Well the horns look like they could be the real deal,but the rest looks like crap. Those cabinets look like they would explode if they were loaded with some 2235,s Still if the horns are intact they would still sound pretty much the same as minty ones,they just would not be as pretty to look at.:applaud:

Ian Mackenzie
07-29-2005, 07:10 AM
Rick,

Great project and very nice job of the cabinets, would love to hear them.

Stick with the original idea and take it to the limit...forget the background noise, its a long way behind you.

Cheers

Ian

saeman
07-29-2005, 08:02 AM
Stick with the original idea and take it to the limit...forget the background noise, its a long way behind you.

Thanks Ian - I hope to hear them myself in 2-3 weeks when the second cabinet is done. From that point I'll work on component upgrades and as I said before, try to do something exotic with the cross-overs. It's not likely that I'll move them along as I have too much time into putting them together. Very few out there can look far enough into a project like this to see the $$$ value in the cabinets. Original always fetches the big $$$. I've sold custom systems in the past and realized about $5/hour for my time. I built these for myself and hope to groom them into something real nice. Time will tell. "Trivia" from the old Bill Cosby series in the 70's. He always talked about taking wood shop when he was in school. When asked how he did, his reply was that he made a lot of mistakes, many mistakes. When he made a mistake he would cut a notch or two in it and give it to his mother telling her that it was an ashtray. So...... if these speakers fail to turn out great I can always cut a notch in them!! Regards - Rick

JBLnsince1959
07-29-2005, 09:09 AM
Just a note to say how good everything looks. I'm not very good building stuff myself and I always admire someone who can. Also, design looks very well thought out.

Since I'm not good at building stuff, not much I can add to what the others are saying.

congrads :applaud:

John
07-29-2005, 11:05 AM
Just talked to the buyer on those westlake horns.

They are going to Hong Kong!!!:(

Mr. Widget
07-29-2005, 11:26 AM
I shipped a set of mine to Hong Kong too... I guess they like 'em big over there.

Widget

John
07-29-2005, 01:09 PM
Yes and even all beat up like that, that guy still got a steal at $200.00:D

Ian Mackenzie
07-29-2005, 05:06 PM
Rick,

Cool.

You can alway mess with it later and having a baseline JBL design from the beginning makes sense but its a journey that I hope you enjoy.

As for mine oddly I restarted the madness after a 26 year drought with a 2 way Altec/ JBL 2397 system about 9 years ago (thats 26 years after my 1st attempt at building 4343's). I then added 077's (since Robert's in NY)..that was a given, then added an 8 inch Audax mid, then a 10 inch 2122 JBL mid (via Robert) and got hold of some 2245's for a nice 4 way. Then I switched to 2344a's which I thought was nirvana at the time and was back to a 3 way. As fate would have it I then made the mistake of hearing my 4343's at my brothers place. The result of that demonstration started me hastled Bo for 4345 measurements...the dang Yankee I love him for that. I bought a pair 2307's off Jon, compared the whole mess.... 2307+2308/2344/2397 and rebuild the cabinets into 4345...that was hard work. I thought the 2307/2308 with the 2122 and 2405 had the most neutral and accurate sound at the time and I am yet to prove to myself otherwise! (Hovlands in the crossovers does wonders as does a mountain of class A power!)

Finished the 4345's .......Game over Man , Game over.

But had I not screwed around with all the other stuff first I would not have appreciated just how good a prime JBL four way design can be.

So go have fun with it and enjoy.

Ian

saeman
07-30-2005, 03:25 PM
Hello Ian: I loved hearing the itterations that you have gone thru before settling back almost to where you began. Sounds so familiar to what I have done. I did a bunch of custom things thinking my 4343's could be improved upon. Went to 2-way and 3-way as that's where I started with JBL, tried all sorts of driver combinations parked in cabinets from big to outrageous and then finally determined that my 4343's weren't so bad after all. I was a happy and settled camper until a buddy of mine gave me a demo on his 4350's running on about 1000 watts/channel of bridged Crown power. After a full demo of everything from Bach to Pink Floyd, I helped him move his house back on to the foundation and we started talking price. Brought them home 3 weeks later. Seemed logical to me. The 4350 was just one small step up from what I already had ??? I'm hoping that this 4351 project will yield some improvements in the system in a home environment. I'll surely keep you posted. Regards - Rick

Tom Loizeaux
07-30-2005, 06:16 PM
Rick,
Don't be haunted by "what you could have done". You are going to have a pair of speakers that will sound better and image better then original JBL 4350s...and that's saying a lot!
Though a Westlake horn could improve things, and trying newer componants might give you a little more, there are usually little problems that come from making these kind of substitutions. It's usually a lot of work (and expense) to make a small gain in these kind of situations.
I'm sure you'll love your 4351s.
Maybe, down the road, with specific help from fellow Forum members, you'll try to upgrade these 4350 componants, but it's not something I think you need to deal with at this point.
I restored my 4343s and, except for upgrading the caps in the crossovers, kept everything stock. I do run them in bi-amp mode, but they are stock componants in original cabinets...and they sound great!

Tom

Ken Pachkowsky
07-30-2005, 11:05 PM
As stated in my first message, you have done a great job and I am sure you will like the speakers you have built. When you’re ready to go to the next level you will find many opinions here.

I have had the privilege of owning factory built 4345's and 4350's as well as Westlakes. The 4345 systems smaller 1” 2421B combined with its longer horn assembly (2307/2308) sounds much smoother than a stock 4350 with (2392?) or whatever that stubby horn is. You can’t compare the sound of a stock 4350 horn to those of the 4345. The difference is staggering. A stock 4350’s horn is simply “ear shattering harsh”. On the other hand the 4345 horn is less harsh, even at high SPL’s.

That being said, a quality wood horn designed for and attached to any 2420/2421B/2440/375/2441 will simply out perform any of these older "stock" horn and lens systems hands down.

Take it from someone who’s owned all the above systems. Once you have listened to a JBL/TAD/Westlake wood horn system, you will never go back to the old standard metal series horns and plastic lenses.

In Ian’s well chosen words “Game over Man, Game over.

Enjoy your new speakers and if I can ever be of assistance don’t hesitate to ask.

Ken

Ian Mackenzie
07-31-2005, 01:47 AM
Rick,

One thing to watch out for is pipe organ resonances with long thin ports.

Probably not an issue below 250 hertz but might be worth checking into.

Ian

saeman
07-31-2005, 08:41 AM
Hi Tom and Ken: Your comments are much appreciated. This project was a deliberate effort to reorient the 4350 components into a more living room friendly array - floor space being the issue. To that end I'll be quite happy. Besides having my 4350's I now have a wall ensemble that will look much better. Any other improvements that arrise will be gravy. I expect getting the mids and highs up off the floor a bit will be an improvement. And as I said, I'll play with them and do some tweeking as time goes on. I'm sure they're here to stay - not remotely interested in carrying them up out of the basement.......But, you guys have peaked my interests in some other areas. Listening is half of my passion and building them is the other half. Nobody has to twist my arm to get me started cutting wood. I intend, later this year, to start another project and will definately tailor it to some of these great ideas. Thanks again http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

saeman
11-26-2005, 08:14 AM
With completion of the grille set, I've finally finished physical construction of my 4351 monitors. Here's a few pics showing the final look (poor light until I get my room refinished). I hope to continue the project with upgraded x-overs (Lancer Style) and upgrade the woofs from 2231A to 2235H when I can locate a quad set. For now I'll just listen and enjoy having a little more floor space (I'll always own a pair of 4350's).

Rick http://audioheritage.org/vbulletin/images/smilies/bouncy.gif

saeman
11-26-2005, 08:15 AM
pics

johnaec
11-26-2005, 08:19 AM
Outstanding! :applaud:

John

DRG
11-26-2005, 08:45 AM
Fantastic work Rick!

I hope you don't mind that I've forwarded these photos to Greg.

Titanium Dome
11-26-2005, 09:30 AM
Great work on the grilles and super set up all the way around.

What's your winter project this year?

saeman
11-26-2005, 10:22 AM
Thanx for the comments. I've burned through about 16 yards of blue Zilch cloth making 11 or so pairs of new grilles and covering a couple others. I now have grilles stocked for all of my projects. Am now cutting wood to finish the pair of 4344's I started a few months ago and hope to have them done sometime in December - not sure where they're gunna go yet as the house is full. I have one of my 4341 pair remaining to be restored and then I'm on to restoring a super early pair of 4350's that I've been anxious to bring back to life. Never a dull moment in JBL World !! I need to somehow put the stoppers on after that and just sit on my ass and listen for a while. We'll see. Rick




Great work on the grilles and super set up all the way around.

What's your winter project this year?

yggdrasil
11-26-2005, 01:35 PM
Very impressing work indeed.

Between those beauties that rather big TV looks really small. :D

Charlie4350
11-26-2005, 02:03 PM
Great work. I could look at those all day - actually takes my breath away.

chuck

bbrown
11-27-2005, 05:10 PM
Two places that could probably help you out to get the blue stain the way you want.

First, the Musical Instument Makers Forum. If you create an account, you can post questions, and they are VERY helpful. You aren't making a guitar, but you want to use a technique that they often use.

http://www.mimf.com/

The other is Luthiers Mercantile International. They have all kinds of finishing supplies, dyes, etc. that could be of use.

http://www.lmii.com/

Those are beautiful cabinets. It would be nice for you to get the blue the way you want them.

Bruce

4313B
05-03-2006, 04:47 PM
All the Solen parts for the biased 3155 equivalent filters.

saeman
05-03-2006, 05:41 PM
Can you say "Awesome" boys and girls? "It's a wonderful day in the neighborhood" for sure.

Most of you guys know me well enough by now to know that I'm FIRMLY stuck in my 70's 43XX/Sovereign groove and just can't see any merit in moving out. Having said that, there's nothing wrong with tweeking these old speakers to achieve their maximum capacity. The prospect of electrons flowing thru modern state-of-the-art x-overs is exciting.

Rick :bouncy:

Charlie4350
05-04-2006, 11:06 PM
Whenever I hear mention of these, it sure get the wheels turning.

Rick, you gonna run those with 40's or 41's?

chuck

Ken Pachkowsky
05-04-2006, 11:26 PM
Excellent work.

Congrats

Ken

QwertyAccess
05-04-2006, 11:28 PM
Very late into the post!, but amazing!, they look beautiful to me :), i hope to have such a project one day.

saeman
05-05-2006, 07:41 AM
Rick, you gonna run those with 40's or 41's?

chuck

Thanks Chuck

When I first built them they were populated with alnico 4350 components which I had on hand at the time. As parts came available I changed them to 2235H, 2202H, 2441 and 2405. They are currently running on 3107's and sound pretty good. I'm sure the new x-overs will lift them to a new level. Cabinet volume is the same as the 4350 and 4355. I'm a bit worried that my 4350 port arrangement may not be correct for the 4355 components. I'll need to get with one of our forum wizzards who has the knowledge and software to determine if I need a change in port size or duct tube length. As you know, building a box is one thing but making it sound the best is another story. This project will certainly be ongoing, at least for a while. I'll keep you posted.

Rick :)

Mr. Widget
05-05-2006, 09:18 AM
As parts came available I changed them to 2235H, 2202H, 2441 and 2405. They are currently running on 3107's and sound pretty good.They must sound a bit bright then.... or at least have fairly indistinct highs.

Even if your new networks weren't charge coupled and even if they were using standard mylars they would be a significant improvement.... as it is you'll be getting new speakers.:D


Widget

saeman
11-03-2006, 03:22 PM
For a friend in Aladambama I build another pair of my living room friendly 4351 Vertical Monitors. They're pretty much identical to mine in finish and components. They were temporarily parked in my wife's living room until this past Saturday when we loaded them for their trip to Birmingham (she was happy to see them go). At 300# a piece I was glad to finish the loading and kiss them goodbye. On to something new. :bouncy:

yggdrasil
11-03-2006, 04:56 PM
:jawdrop: ......

Chas
11-03-2006, 05:16 PM
Unbelievable! You are amazing churning out these masterpieces.
Damn fine work:applaud:

NancyJ
11-03-2006, 08:08 PM
As stated in my first message, you have done a great job and I am sure you will like the speakers you have built. When you’re ready to go to the next level you will find many opinions here.

I have had the privilege of owning factory built 4345's and 4350's as well as Westlakes. The 4345 systems smaller 1” 2421B combined with its longer horn assembly (2307/2308) sounds much smoother than a stock 4350 with (2392?) or whatever that stubby horn is. You can’t compare the sound of a stock 4350 horn to those of the 4345. The difference is staggering. A stock 4350’s horn is simply “ear shattering harsh”. On the other hand the 4345 horn is less harsh, even at high SPL’s.

That being said, a quality wood horn designed for and attached to any 2420/2421B/2440/375/2441 will simply out perform any of these older "stock" horn and lens systems hands down.

Take it from someone who’s owned all the above systems. Once you have listened to a JBL/TAD/Westlake wood horn system, you will never go back to the old standard metal series horns and plastic lenses.

In Ian’s well chosen words “Game over Man, Game over.

Enjoy your new speakers and if I can ever be of assistance don’t hesitate to ask.

Ken
Gentleman Ken, excuse me for butting in here but, I love the 4350a's I have and have like many of you guys, looked at the various horns, I love JBL stuff $$$$$$$$$.
Now I have a serious interest in the BMs planar horns. Anyone here familar with these animals?
A couple of weekes back I had joked about flipping my 4350s over to gain some floor space so with a very welcome heart I am enjoying these trials and tribulations. also what was the active crossover for the 4355?
No this is the best project that would solve so many problems for me.
Thanks Rissen! very nice! :D

spkrman57
11-03-2006, 08:10 PM
this is a great thread....;)


I like the end result of the vertical orientation......:D

Regards, Ron:)

cvengr
11-05-2006, 02:05 PM
I've been dabbling with the similar exercise on tranducer arrangment.

Several questions have arisen. I'll toss these out and hope some ight have particular responses to some of the questions and possible solutions I've pondered.

1) What minimum and maximum separation is recommended between the 2235H frames? ... baffle cutouts?

Minimal separation constraints:
a) Structurally, we could always go to a steel wide flanged angle idea between the 2 speakers to maintain cabinet structural integrity, thereby reducing the floor space. This means it might be as minimal as the width of say a 1/2" steel plate custom shaped to maintain a 90 degree (or variant) angle between baffle and cabinet base, thereby also allowing the plate to be drilled and tapped to allow 2235 mounting hardware attached to a common axis. Vibration analysis might be appropriate.

b) Electromagnetically, if we are inducing the same signal from the same source to both 2235Hs, then are we might be increasing some magnetic field interference between the 2 woofers. Negligible perhaps? I haven't quantified this to discern at what amplitudes such field interference might occur. If the effects occur, I suspect they would tend to oblate the field forces on the voice coils hence their respective cones, but perhaps no greater than transient overtones from a universal spectrum of music reproduced on the system.

c) Acoustically, once the sound wave emanates from the 2235s, are their harmonic separation distances one should discourage in the 2235 placements?

Maximum 2235 separation constraints:
a) In constructing a Helmholtz resonator, is the separation distance between the 2-2235H woofers integral to the cabinet depth? .. port distance from the cone? port depth? What eqns are generally assumed/used in speaker design for Helmholtz resonance? I tend to think symmetry wrt to the enclosure volume and the 2235 placement is simplest, but the original 4350/55 didn't respect that perspective, so maybe it isn't significant.

2) Location of the mid-bass with respect to the Bass? wrt the Mid range compression horn?

3) In considering the alignment of voice coils, some recommend aligning all voice coils along the same plane such that the electric signal from the sound system reach the voice coils concurrently and their conversion from electrical energy to mechanical kinetic energy occurs concurrently, thereby reducing timing problems between transducers and signal paths.

If I worry about cutting all my conductors to the same lengths between the electronics/ power amps and the speakers, then it would also seem significant to align the voice coils.

In my case I have 2-2235H, 2-2202J, 2-2440J with 2390 horns (12"deep) +serpentine lens, 2-2405s.

I'm experimenting first with some deeper boxes (24" ext, int 21-7/8") since the JBL enclosure guide recommended 5cuft per 2235 per encl) using some free plywood, playing with configurations, toying with integrating some sand filled walls, and incorporating the mass into cabintry to hold records, some electronics, and all the while playing with some architectural furniture themes.

The 2390s have given me cause to deepen the cabinets, and make some options open to also consider some horn loading on the low end.

If we align the voice coils, I'm afforded about a foot of depth in the front of the cabinets, but if calculated the reduced acoustical impedence of that effort may effect the xover design.

This leads me to quesry what the differential/integral format eqns are describing the acoustical impedence.

Probably enough here for several threads, but they all seem pertinent to the particular issue of a 4351 variant.

quindecima
11-06-2006, 06:39 PM
If you want to get a nice blue you need to bleach the fronts white and then go over it with a white stain that has blue added to it to make it the blue you want. I used to sand and finish hardwood floors and we would make floors different colors by this method. I know it sounds like the wrong way to go but believe me if you want a nice blue or any other color for that matter it will work well. Use a non-yellowing finish, swedish Glitsa or water base. Make sure the bleach dries for 2 or 3 days before it is stained. The bleach is a two part system.

4313B
01-06-2007, 08:41 PM
riessen,

I finally got around to tweeking the biased equivalent bandpass filter on the 2441 today and compared it against stock. I think I've nailed it.

This is real life:

saeman
03-23-2007, 10:17 PM
My 4351 project started out with the desire to create a 4350 system that didn't take up as much valued floor space AND to get the mid range and high frequency drivers up into the listening area.

Initially these cabinets were loaded with standard 4350 components, including NOS 3107 cross overs. One thing led to another and I decided to upgrade them to 4355 configuration, lacking the ability to include the factory 3155.At that point Giskard jumped in and offered to develop and build a custom charge coupled version of the 3155.

As of today the new networks are fully installed and the system is up and running as the JBL Gods intended. It may be just my imagination but they seem to have taken on a new image. One thing for sure - the 2441's are now on par and flat with the rest of the components. Running them with the 3107's gave them a dominating presence and at the higher end they literally screamed at you.

I spent a few hours so far listening to everything I could find that I have extensive listening experience with on this system, my 4350's, etc. and their performance is outstanding. It will be some time until I can get my speaker storage room converted back into my listening room. I will then be able to do some serious listening/testing.

All interested should give these new networks a spin - cost is very fair considering all of the R&D time involved and the cost of the high quality components used.

Rick :bouncy:

Ken Pachkowsky
03-23-2007, 10:20 PM
Always great to see reports on your projects.

Thanks

Ken

4313B
03-24-2007, 05:44 AM
http://audioheritage.org/vbulletin/showpost.php?p=110284

It has been awhile and some of the parts in that drawer were substituted with different values to get the networks "right" according to CLIO and LEAP. As G.T. heartily suggested third quarter of last year, LEAP ended up being the fourth Ace in the hand. I really like the way they ended up sounding.

The 3144/3145 bi-amp only networks should be finalized by the end of April at the very latest. There will be three versions. 1st will be with the stock 1" compression drivers and stock horns, 2nd will be with the 1.5" compression drivers (435Be) and subwoof horns, and 3rd will be with the TAD compression drivers on the stock horns.

yggdrasil
03-24-2007, 11:32 AM
Rick those speakers are awesome and really deserve the new networks.

BTW Giskard - your networks are truly beautyful.

MatthiasA
10-30-2007, 04:52 AM
very goood veryyy gooooood !!!!!!!!!!!!!!!! :applaud::applaud::applaud::applaud:

which material is the polyester cotton and the grill ?
and where do you get this ? how much is ist ?

thanks matthias

JBL 4645
10-30-2007, 05:55 AM
Now all that’s needed is special design for the centre channel because that small centre channel above the TV monitor will not cut it against those titanic monstrosities, wow there's enough of those 4351 in that room to sink a battle ship. :applaud:

Huynh Chau
05-22-2008, 08:33 AM
My 4351 project started out with the desire to create a 4350 system that didn't take up as much valued floor space AND to get the mid range and high frequency drivers up into the listening area.

Initially these cabinets were loaded with standard 4350 components, including NOS 3107 cross overs. One thing led to another and I decided to upgrade them to 4355 configuration, lacking the ability to include the factory 3155.At that point Giskard jumped in and offered to develop and build a custom charge coupled version of the 3155.

As of today the new networks are fully installed and the system is up and running as the JBL Gods intended. It may be just my imagination but they seem to have taken on a new image. One thing for sure - the 2441's are now on par and flat with the rest of the components. Running them with the 3107's gave them a dominating presence and at the higher end they literally screamed at you.

I spent a few hours so far listening to everything I could find that I have extensive listening experience with on this system, my 4350's, etc. and their performance is outstanding. It will be some time until I can get my speaker storage room converted back into my listening room. I will then be able to do some serious listening/testing.

All interested should give these new networks a spin - cost is very fair considering all of the R&D time involved and the cost of the high quality components used.

Rick :bouncy:
Hello Seaman
I am trying to find a measures CAD Raw cabinet of JBl 4351 .If You has the measurements available, I would be really grateful to get a copy!

My Email : [email protected]
Thank

dkalsi
08-22-2009, 08:18 PM
For a friend in Aladambama I build another pair of my living room friendly 4351 Vertical Monitors. They're pretty much identical to mine in finish and components. They were temporarily parked in my wife's living room until this past Saturday when we loaded them for their trip to Birmingham (she was happy to see them go). At 300# a piece I was glad to finish the loading and kiss them goodbye. On to something new. :bouncy:

I'm in the process of collecting components of my own JBL studio monitor build. I have been researching the forum for other DIY projects... but when I saw this ... I was in total aw...

Now this project is truely a work of art. -- (See post # 89)

bldozier
10-05-2017, 04:15 PM
Nice work!

You've obviously come to a point where you know the sound you like... :applaud:

If I were going the 43XX+ route I think I'd go with a 4345 but swap out the 2421 with a 2441 and a Westlake horn... just my take on it. As for tower configurations, this is what Westlake did. It is a real monster with dual 18" woofers!

Widget

where would the horn go? outside.

GUYGELLA
06-07-2021, 05:40 AM
I am trying to build my own 4351’s.. I need the outer overall measurements and the port size & length. Any help would be appreciated.

RMC
06-08-2021, 12:57 AM
Hi Guygella,

Since you said "Any help would be appreciated."

I think i have some of the 4351 information you are looking for. Well, there's one twist its in Japanese language i don't speak, not the easiest one to read either, however numbers remain numbers and that's what you're interested in. I was able to figure out a couple of things like dimensions, but certainly not all there is.

A professional translator would be expensive, see if you have a Japanese friend or neighbor, or better yet find a Japanese girlfriend (lol) and you might be in business! A not too expensive alternative could be to eat in a Japanese restaurant and have someone there do a little translation of important stuff for you in exchange of extra gratuity. Gotta do what you have to do...

The JBL speaker builder material on-hand gives port dimensions for a number of models, not for the 4351 though. However there are some ways to "reverse engineer" such port, not really difficult when having some basic data but it takes a little time... Btw the 4350B seems to use similar port diameter but length may be different.

Let me know here if you're still interested in the data.

I can't post it here but if you send me a Private Message with an e-mail address i could forward the info to you. Regards,

Richard

duaneage
10-01-2021, 08:42 PM
If you have a 4350 system it would be possible to test your drivers for box tuning and impedance then move to the 4351 and run the same tests. You can measure box volume accurately by closing all the ports and observing the change in resonance of the drivers compared to free air resonance. Both the 4350 and 4351 should have the same result and solid fill or fiberglass can be used to make them.the same.
With the same volume you can approach tuning. Cut just one tube of the 6 to fine tune them.