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JBLnsince1959
11-08-2006, 06:59 PM
Well, drove to spkrman57s' place in Columbus Ohio from Kansas City this last weekend to pick up the 250 boxes he had for sell. Loooooong ass drive back and forth, but it was worth it.:bouncy: believe or not we put them in the trunk of a Ford Contour. Ron really knows what he's doing when it comes to putting 10LBs of sh*t in a 5LB box

in the little time I was there, I had a great time. I had wanted to stay over Sat. night, play with speakers, get wasted and take pictures of his incredible house of goodies:applaud: , BUT, the lady had other ideas

Ron is a super nice guy and everything that's in his house is simply jaw-dropping..:jawdrop: amazing.... just amazing.

Ron, I really enjoyed listening to your horns and tube amps( in the pictures)...Once I'm done with the PS/250 stuff I'm back to horns and tubes myself for the next project. Wish we could have had the E130's ready to go with the horns..maybe next time...;)

Thanks again for the great hospitality..just wish I could have enjoyed a couple of "cold ones"

Here's some pictures of us..( I'm in the solid blue shirt) and Whit!!!!

Titanium Dome
11-08-2006, 11:50 PM
So, we going to see the boxes you got, and are you going to tell us what you plan to do with them?

JBLnsince1959
11-09-2006, 03:49 AM
So, we going to see the boxes you got, and are you going to tell us what you plan to do with them?

sure, when I get time. the trip didn't go as I had planned. We had hoped for a lot of pictures of the 250 boxes, Rons' house and all the goodies, the speakers in the trunk BUT...things didn't go as planned.


As mentioned in the thread in the Marketplace, I'll be putting the Transducers from the PS series into the 250 boxes. I guess that will be a thread in DIY forum. I'll try to get some pictures of the boxes and post them in a week or two but it will be around next March when I get going on the project for real.

Rolf
11-09-2006, 10:32 AM
Very interesting what you are going to do with the boxes. Looking forward to pics.

So you brought your "faithful" on the long drive? Guess she loved it. They always want to go no matter what.

spkrman57
11-09-2006, 12:33 PM
It was fun to meet and discuss our JBL ideas and such. Too bad we did not have more time together like you said.:(

The round wooden horns in the pics are Edgar 500hz tractix w/GP 399 driver(288-8K clones), they are 1.4" and sound nice to me at least.:p

I can't wait for Rick to install his performance series drivers in the 250(variant) cabinets.:applaud:

Thanks for stopping by!:D

By the way, Whit is a very well behaved dog! That's good as she hits the scales at just over 100 lbs. Too bad she did not have much room to get around inside my house!:bouncy:

Regards, Ron

Robh3606
11-09-2006, 07:43 PM
Are those the prototype boxes??? Would love to see them loaded up in someone's livingroom!! That would be cool! Talk about a unique one of a kind system:bouncy:

Rob:)

spkrman57
11-10-2006, 07:01 AM
They are traveling around the JBL fanclub circuit.

Who knows where Blaster got them from....


Ron

JBLnsince1959
11-10-2006, 08:37 AM
So you brought your "faithful" on the long drive? Guess she loved it. They always want to go no matter what.

By the way, Whit is a very well behaved dog! That's good as she hits the scales at just over 100 lbs. Too bad she did not have much room to get around inside my house!:bouncy:

Regards, Ron



yes, Whit goes everywhere with me and is with me all day at work too. If I go to the store and don't take her, she sits by the door "crying". God have I spoiled this dog. She's really a sweet, sweet soul and typical GS wanting to be with and please her owner. She does great on long trips in the car. We even took her to Yellowstone Park this summer. She get's a little edgy at someones house for the first hour or so because she doesn't know what's happening ( she was pound dog and maybe thinks shes going to be left off), but then she calms down and is just her regular self. When we stayed at Rusnzhas' house this Labor day weekend, she just stayed in the back yard and house ( SH*T - I forgot to do a thread on the visit :banghead: - sorry Russ, that was a great experience and I didn't "Doc" it)


Very interesting what you are going to do with the boxes. Looking forward to pics.

.

Are those the prototype boxes??? Would love to see them loaded up in someone's livingroom!! That would be cool! Talk about a unique one of a kind system:bouncy:

Rob:)

Rob:
yes, those are the ones, they even have the "infamous" GT proto type tags on each of them. I've only looked them over for 5 minutes or so once I got home, but DAMN if they don't look like the real thing:hmm: . The sides and top are even finished ( which doesn't show in the picture). Maybe we'll do a comparison of the cabs and construction techniques against the ones Dome has. Who ever built them did a great job.....

These are the perfect speakers for this experiment as they don't have the 250 Tweeter housing that sticks out of a normal 250. One thing that concerned me was having to "Cut" that out of a regular 250 cab to make the EOS waveguide fit. So these are a gift from GOD and the reason I jumped on them so quickly and traveled so far.

I'll go into more detail later ( got to work) and get pics this weekend...

the basic plan is this
1. have Ian build active crossovers between the LE14H-3 and 908Ti. for now I'll use the amp inside the PS1400 for the bass
2. Build passive crossovers using Clarity caps and other good parts for the "PT800" part ( I'll test out different caps and CC'ing over the years and post)
3. Make everything fit...I'm thinking of doing like the Ultima2 Series by Revel and making raised curved mountings for the trans to sit in....this will help "fit" the trans. into the baffle, help with the placement of the trans. for time aligment and may reduce refractions( will cover the mountings with felt)

One of my lady's uncles owns a cabinet making company up around St. Joe Mo. I may have to have his help making the correct mountings for the Trans...

Once I start the thread in DIY forum I may need all the help I can get from you guys as you know way more than I do on the tech end of things.

Well, the mystery 250 "proto type" cabs have finally found a permanent home. I'll never get rid of them...this should be fun:bouncy:

have a good day everyone:wave:

JBLnsince1959
11-10-2006, 08:38 AM
They are traveling around the JBL fanclub circuit.

Who knows where Blaster got them from....


Ron


I've been wondering about that myself...would be interesting to "trace' them back thru their owners...

Robh3606
11-10-2006, 10:18 AM
I saw them on E-Bay a couple years back. I am sure they were the same ones. Would be fun to find the lineage on them.

Rob:)

JBLnsince1959
11-12-2006, 09:18 AM
So, we going to see the boxes you got?

Your wish is my command...everything in it's own time....

below are pictures of the mystery XPL250 " Prototype" boxes. Seeing how I plan to put the PS series transducers in them the term "prototype" seems most appropriate

JBLnsince1959
11-12-2006, 09:22 AM
other views

Titanium Dome
11-12-2006, 10:46 AM
Those pictures really shed new light on the cabinets.

What is that black covering? It doesn't look like Neoprene in the pics. It looks like a glued on covering of some sort. Is it flush with the sides and front baffle, or does it stick out due to its dimensional thickness?

Are those baffle openings what we'd expect? Looks like maybe 035TiA was front mounted at the top. The mid must have been an 095Ti. The midbass probably a 108H with an LE14H-x at the bottom?

I see some wiring sticking out of the 8" opening. Are the rest of the transducer openings also wired?

Looks like an exciting opportunity for you. :bouncy:

JBLnsince1959
11-12-2006, 01:07 PM
What is that black covering? It doesn't look like Neoprene in the pics. It looks like a glued on covering of some sort. Is it flush with the sides and front baffle, or does it stick out due to its dimensional thickness?





Not sure it's like a rough woven fabric....spkrman57 may be able to shed more light on that. It is not flush but is glued on, so it sticks out.


Are those baffle openings what we'd expect? Looks like maybe 035TiA was front mounted at the top. The mid must have been an 095Ti. The midbass probably a 108H with an LE14H-x at the bottom?



the tweeter hole will fit a 35tia flush mounted perfectly ( not sure what was meant to be there) and the mid-range will fit a 93 perfectly according to spkrman57..

the bass looks standard and what we would expect.

Of course I haven't had much time to look at them or compare. I'll post more about them and the holes at a later date



I see some wiring sticking out of the 8" opening. Are the rest of the transducer openings also wired?



the wiring you see is the wire going thru the8" sub-cabinet... the sub cabs for the mid-range is no longer there ( I feel part of it inside - or what I think was it)

the tweeter has no sub cab either, but part of a ring of silicone appears to be inside..

the more I think about this the more strange they are..

I'll have to post more later..

looking at the back and upper corners, how do they compare with yours???

Titanium Dome
11-12-2006, 02:51 PM
My L250 cabinets have two removable panels on the back. At the top is a panel that must be removed to access the 044-1 from the rear for removal. Below that, the entire rest of the rear panel can be removed by taking out numerous screws. However, since all the rest of the drivers are removable from the front, there's no need to go to that trouble.

The cut outs on the back look typical for an L250 cabinet, with the big opening for the crossover and attenuation bars.

The sides look like stock L250.

The front is a bit of a conundrum. There are no speaker grille mounting holes on the baffle, so again it looks more like an L250 cabinet, but otherwise it's like a completely different baffle from the 8" hole on up, plus the solid wood quarter-rounds and 044-1 ring don't seem to be there. I wonder what it looks like underneath that black paint and that glued on sheet?

northwood
11-12-2006, 03:30 PM
Is Ron the long-haired one?He looks like a Hollywood actor very much,sorry I can't remember that guys name:D

JBLnsince1959
11-12-2006, 03:45 PM
Is Ron the long-haired one?He looks like a Hollywood actor very much,sorry I can't remember that guys name:D

No, I'm the long haired one... ..second picture I'm on the right side of the picture next to my dog Whit ( had to get her to look in the camera..)

as far as looking like a hollywood actor...:rolleyes:

Titanium Dome
11-12-2006, 03:57 PM
I'm staring at my L250s and there's at least another cosmetic difference. Your cabs don't have the routered black line about 4" up from the base. :hmm:

JBLnsince1959
11-12-2006, 04:40 PM
I'm staring at my L250s and there's at least another cosmetic difference. Your cabs don't have the routered black line about 4" up from the base. :hmm:

I've thought about that myself..however, if the solid wood quarter-rounds you're talking about are on the very top right and left rounded edges..yes, they're there..


Interesting boxes for sure..of course my main concern is getting the PS series in and I'm going to measure and start working on plans tonight...still they don't look like home made boxes someone just put together...:hmm:

compare the back and transducer cutout's with the only known XPL250 prototype..

JBLnsince1959
11-12-2006, 05:46 PM
All I know is someone did a good job of building these. They are much better than I expected and I'm really pleased with them. :bouncy:

They are perfect for what I'm wanting to do.

Now, I've been wondering, should I leave the EOS waveguide flush with the baffle or should I build a tweeter ring like the 250 has??? I'll need some advice from smarter people than me.

spkrman57
11-13-2006, 07:54 AM
It seems to me to be the same as pro-sound guys put on their gear. Almost like a fuzzy capet type.

Maybe Blaster will chime in here and give us more history on these!

Ron

Titanium Dome
06-09-2007, 02:37 PM
Hey '59, what ever transpired with this project? I think about it once a month and check the thread, but there's never any news.

JBLnsince1959
06-12-2007, 03:06 PM
Hey '59, what ever transpired with this project? I think about it once a month and check the thread, but there's never any news.

hey Dome....:wave:

Well a number of things got in way this year......Number one was my health and also something called "MS Vista". I write and design computer software so everything had to be checked out ( many surprises in that puppy). My health caused me to get behind so i've been working very hard and long days.

If I do this ( or WHEN I do this) I want it done correctly so there's much to consider. I had planned to start on the project last March BUT my body had other ideas.....

Number 1 issue to research is the crossover and see if it needs changing because of the different baffle, if so then I'll need all the data for the transducers and some help from those great people on the forum who know more about this than i do. If we can use the same design then it's just a matter of making a new CC crossover for the 800 part. I PM'ed a little ( very little really) with Ian last year on making an active to go between the 1400 and 800 but we haven't gotten into any real details...

2. the cut-outs for the transducers. I'll need to do a careful comparison of the holes in the 250 boxes to the ones in the PS series and then design and plan away to make the baffle fit them. ( will most likely cut out sections and refit new sections in the baffle) .

3. next I may need to build boxes for the tweeters and other 800 trans and get them inside the 250 boxes and mounted to the front baffle. Don't want to blow out tweeters. I think there's a box for the mid-range already.

anyway, i quess a thing called life got in the way. The project is still there in my mind, but i've just had other things to do and take care of and of course medical bills didn't help either. after the "scare" this year I'm spending more time with friends and family and less time on the forum. it did a real job on my thinking

Thanks for thinking about project. When i do start it for real i'll post in the DIY forum.

hope all is well with you Doug...

take care

sourceoneaudio
06-14-2007, 08:16 AM
compare the back and transducer cutout's with the only known XPL250 prototype..


The front panel of the prototype looks a lot like the 1992 German version.

http://www.lansingheritage.org/images/jbl/catalogs/1992-german/page08.jpg

Note the tweeter is flat, no angled ring to put the 044Ti driver on a 90 degree face.




3. next I may need to build boxes for the tweeters and other 800 trans and get them inside the 250 boxes and mounted to the front baffle. Don't want to blow out tweeters. I think there's a box for the mid-range already.



Also JBLsince1959, I would not worry about blowing out the tweeter. All of the 250 series speakers are open from top to bottom. The only drivers that require a separate cabinet are the 140H and the 108H, being ported I don't see the tweeter popping out on the floor.

Jeff
J/S-S1A :D

JBLnsince1959
06-14-2007, 01:36 PM
Hi sourceoneaudio:wave:

yes, I've seen those in germany and almost bought a pair for the fun of it ( didn't want to hassel HP too much). But also, those are not 250's but somethig else. I was mostly comparing directly to the Ti250 in this thread... I hadn't thought about those tho when thinking about this

I'm not going to build a Ti250, but instead put the transducers from the PS series in the 250 boxes.

as far as the tweeter, well it's not the tweeter per say that i was concerned about but the ESO wave guide, not sure how much pressure it can handle from the 14". Most likely won't be a problem BUT....Giskard and i discussed this a little last year but neither he nor I were sure....This maybe one of those things where better safe than sorry. I don't think the parts are available for that if something goes wrong.

Personally I'll like to find another tweeter, build my own EOS waveguide out of wood and redo the crossovers. But that maybe too much for too little ( welllllll.....a Be tweeter would be worth it;))

thanks for the comments...well Dome and you have me back thinking about this project again.....guess i'll have to pull the boxes out of storage and get real on this. Once i do start this feel free to join in on the tread...

take care

Titanium Dome
06-14-2007, 01:56 PM
If you go here, you can get a TM025F7 Ti 1" dome for under $20. This may be a better application than the PT800 tweeter and EOS Waveguide. It basically has a built-in waveguide, though it's non-EOS. You could always adapt it for your purposes, while keeping your PT800 tweeters intact.

http://www.amazon.com/s?ie=UTF8&rh=n%3A281407%2Cp_4%3AAudax&page=1

JBLnsince1959
06-14-2007, 02:38 PM
Thanks Dome...

some very good information there and i'll consider it.. I'll have to think seriously about a different tweeter, at least in the beginning.. for me it would be easier to fit the EOS waveguide into the boxes than to redesign the crossover for a different tweeter. If I were to go that route then i'll try to find a Be tweeter.

the tweeter that's in there is a good one, not great, but good. In the "first phase" I'll most likely use what's there as far as trans and crossover design ( CC'd of course) to keep it as simple as possible. From there we can get some measurements and do some listening to see if we need to do more or if I feel the need to experiement.

there's making changes that make it sound better and then there's making changes to just make it sound different. Knowing the difference is what separates the men from the boys...

I'm sure I'm going to need all the help i can get with this....

sourceoneaudio
06-14-2007, 03:28 PM
I knew you were referring to the 250's for your project. The reason I posted that link is the cabinet face design on the XPL Proto you posted, is the same as the German model.

Have you thought of using the 035Ti? That looks to be what was used in that XPL prototype front mounted, and that was the driver used in the 250Ti LE front mounted.

Here is a set of 035TiA's for sale on the bay as we speak.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=010&sspagename=STRK%3AMEBI%3AIT&viewitem=&item=200118882346&rd=1&rd=1

As in your tweeter mounting concern the 044Ti would not go anywhere since it is rear loaded, that would also be another option. If you don't have a rear shot of the 044Ti I have one for you to look at, and also the midrange enclosure. Midrange enclosure dimensions are 3-5/8" deep and 5- 3/4" outer dia.


Jeff
J/S-S1A :D

Titanium Dome
06-14-2007, 03:34 PM
Thanks Dome...

some very good information there and i'll consider it.. I'll have to think seriously about a different tweeter, at least in the beginning.. for me it would be easier to fit the EOS waveguide into the boxes than to redesign the crossover for a different tweeter. If I were to go that route then i'll try to find a Be tweeter.

Yes, Be would be nice. The reason I mention the Audax is because the PT800 TM025 is an identical driver in a different mount.

JBLnsince1959
06-15-2007, 05:42 AM
The reason I mention the Audax is because the PT800 TM025 is an identical driver in a different mount.

Thanks, I saw your other post where you discussed this at length. I figured when the time came I would call you and talk about what you found. As I said, I haven't been on the forum much lately nor have i really had the time ( OK, I didn't make the time;)) for in depth research.

love the work you did on this.

I'll most likely get real in late Sept as i have dead lines this July and august...

JBLnsince1959
06-15-2007, 06:44 AM
The reason I posted that link is the cabinet face design on the XPL Proto you posted, is the same as the German model.



Yes, I understand.. I originally thought about the design simularities when I first saw GT's speakers, and it did raise questions in my mind. I didn't think much about the Ti5000's because they are 3 ways using a 12" 2 5" and a tweeter... mostly tho it was because of the height of the tweeter in the Ti5000 that I didn't spend too much time on it.

the 250 boxes with their height raises ( excuse the pun) some interesting design considerations for the tweeter .

we have 3 situations here to consider
1. Flush with baffel ( used in Ti5000 and GT's prototype )
2. Mounted on raised area ( standard 250 design)
3. EOS wave guide

the main question is what mounting would sound best for the EOS wave guide on the 250 box.....While I'm aware of the Ti5000, the closest speaker to what I'm going to do ( as far as the tweeter is concerned) would be the new "version" of the ti5000; the L260. However, here again it's also a 12" and not as high as the 250 box.

Basicly my "mission Statement" on the project is this..

to place the tranducers from the PS series into a single baffle box and the 250 box is the most logical candidate

the reason for this is as I've said in other threads is simply that as I listened to the PS series in two channel I was amazed at how good they sounded. Basicly the PS series is a HT modular design and from an audiophile consideration the design has everything going AGAINST it. YET, seeing how good they sound as they are, I want to see how good they can sound in a more "audiophile" design. I made small half-ass changes to the baffle of the PS series and the changes were both noticable AND an improvement in clarity and imaging.....

well, i have to get to work
take care


to be continued....

Titanium Dome
06-15-2007, 08:11 AM
Basicly my "mission Statement" on the project is this..

to place the tranducers from the PS series into a single baffle box and the 250 box is the most logical candidate

the reason for this is as I've said in other threads is simply that as I listened to the PS series in two channel I was amazed at how good they sounded. Basicly the PS series is a HT modular design and from an audiophile consideration the design has everything going AGAINST it. YET, seeing how good they sound as they are, I want to see how good they can sound in a more "audiophile" design. I made small half-ass changes to the baffle of the PS series and the changes were both noticable AND an improvement in clarity and imaging.....

well, i have to get to work
take care


to be continued....

It would be interesting to hear and compare the in-wall units from the Synthesis Four system (S4VC) that duplicates the PT800s drivers. This THX version would certainly have a "lot of baffle" when mounted flush on the wall.

The downside of course is that there's no LE14H-1 in that mix, but it would still allow a comparison of the three Ti drivers in two design applications. Unfortunately, I have never met anyone who had any of these units, so...

JBLnsince1959
06-15-2007, 02:31 PM
It would be interesting to hear and compare the in-wall units from the Synthesis Four system (S4VC) that duplicates the PT800s drivers. This THX version would certainly have a "lot of baffle" when mounted flush on the wall.

The downside of course is that there's no LE14H-1 in that mix, but it would still allow a comparison of the three Ti drivers in two design applications. Unfortunately, I have never met anyone who had any of these units, so...

yes, it would be interesting...Seems like someone would have have them on display in Ca.

while we're here talking about both the 250's and PS series I'll ask a question about something you posted in another thread ( didn't want to take it off track)



1st Place: Performance Series stacks–clear, articulate HF, gorgeous MF and LF, stupendous cannons!
.
7th: L250–weak HF, strong MF and LF, weak cannons

The PS really set the bar for the power of the cannons, and I was very disappointed by the L250's performance in this regard.


do you think the difference in performance with the canons between the LE14 in the 250 and the PS is the fact that the 1400 has a 400 watt amp built-in? BTW what amp were you using with the two systems....

By all accounts the 250 should have a "deeper" bass since it's volumn for the 14 is ~4CF and the 1400 is smaller.

another reason maybe the 908Ti...I'm not sure what the fundamential note of a cannon blast is BUT if it's below 130 then several harmonics would be played by the 908Ti and seeing how clear they are, that could help also. For example, when Russ ( Rusnzha) was here, we stuffed the 800's with speaker stuffing and Russ could hear "better" bass. Of course it was only changing the harmonics of the bass notes ( at a certain point we mainly perceive bass notes by their harmonics and not the fundamential itself)

an interesting comparison would be the PS series and the 250 bi-amped with a 400 watter for the bass.

Titanium Dome
06-15-2007, 03:52 PM
do you think the difference in performance with the canons between the LE14 in the 250 and the PS is the fact that the 1400 has a 400 watt amp built-in? BTW what amp were you using with the two systems....

By all accounts the 250 should have a "deeper" bass since it's volumn for the 14 is ~4CF and the 1400 is smaller.



an interesting comparison would be the PS series and the 250 bi-amped with a 400 watter for the bass.

They were driven by a Hafler SR2600 (600W/ch @ 8 Ohms), so the L250 shared 600W among all the drivers while the PT800 shared 600W among its three drivers and the PS1400 had 400W all its own.

I also think that the dual, front-firing FreeFlow ports might have had something to do with it. The L250's rear port needs good placement for maximum operation, and it didn't have that. My impression is the the FreeFlow ports work well in virtually any environment that has clear space in front.

4313B
06-15-2007, 04:31 PM
Was the crossover frequency between the LE14H-1 and 108H in the L250 the same as the crossover frequency between the LE14H-3 and 908Ti in the Performance Series? Was the system damping the same for both systems?

By all accounts the 250 should have a "deeper" bass since it's volumn for the 14 is ~4CF and the 1400 is smaller.The increased enclosure volume of the L250/250Ti box is a very desirable thing, something the PS1400 unfortunately couldn't take advantage of due to design contraints.

BTW - many people who have upgraded to the 250Ti networks from the L250 networks have remarked about the improved low frequency response and that can only be attributed to a change in system damping and transducer bandwidth.

I think a DIY project consisting of putting Performance Series components in an L250/250Ti-type enclosure could be a worthwhile endeavor. I would set it up for bi-amp only.

Ron is a super nice guyAgreed!

Titanium Dome
06-15-2007, 07:55 PM
L250: 400Hz, 1.5kHz, 5kHz @ 90dB sensitivity
PS stack: 130Hz, 650Hz, 3.2kHz @ 91dB sensitivity

MJC
06-16-2007, 09:59 AM
It would be interesting to hear and compare the in-wall units from the Synthesis Four system (S4VC) that duplicates the PT800s drivers. This THX version would certainly have a "lot of baffle" when mounted flush on the wall.

The THX in-wall system is designed for HT. I've read elswhere, that having HT speakers in-wall tends to hide the speakers(I don't mean visually) to give an enveloping all around sound.
But for audiophile stereo setup you want your speakers well away from all walls. As one speaker designer I know in Reno has said, "walls never did speakers any good."
He had his speakers at least 15' away from all walls, and the soundstage was amazing.

Titanium Dome
06-16-2007, 10:09 AM
He had his speakers at least 15' away from all walls, and the soundstage was amazing.

He's lucky to have a room that is 40' wide. That's assuming at least 10' between the speakers themselves; maybe he has them closer together than that.

That's a seriously huge room, probably bigger than my whole middle floor if it's 40x50 or so. Most of us have rooms far smaller, like about 2530% of that.

Aspira para ser un peon.

MJC
06-16-2007, 11:01 AM
He's lucky to have a room that is 40' wide. That's assuming at least 10' between the speakers themselves; maybe he has them closer together than that.

That's a seriously huge room, probably bigger than my whole middle floor if it's 40x50 or so. Most of us have rooms far smaller, like about 25–30% of that.

Aspira para ser un peon.
It was on the second floor of his office building. The guy is an electrical engineer, who's main game is designing coffee roasting analyzers, that are used around the world. Speaker building is his "side job".

JBLnsince1959
06-17-2007, 06:51 AM
They were driven by a Hafler SR2600 (600W/ch @ 8 Ohms), so the L250 shared 600W among all the drivers while the PT800 shared 600W among its three drivers and the PS1400 had 400W all its own.



thanks for the info Dome, that clears up a few questions I had in my mine....



The increased enclosure volume of the L250/250Ti box is a very desirable thing, something the PS1400 unfortunately couldn't take advantage of due to design contraints.



thanks for chiming in Giskard. Sometimes I think I should write a book titled " Everything I know about L250/Ti250's I learned from Giskard";)



BTW - many people who have upgraded to the 250Ti networks from the L250 networks have remarked about the improved low frequency response and that can only be attributed to a change in system damping and transducer bandwidth.
quote

Can you explain the details on this a little more if you have time?


I think a DIY project consisting of putting Performance Series components in an L250/250Ti-type enclosure could be a worthwhile endeavor. I would set it up for bi-amp only.


10-4 on the bi-amp BIG TIME.....first thing I though about( OK, second thing:p).

as far as a worthwhile endeaver I beleive it is. I'm not usually a DIY kinda guy. Dont get me wrong, I'll make changes to a system but only after i've talked to people more knowledgable than me and ONLY after seriously thinking about it, I'm very careful in that regard. I guess you could say I'm not a Q&D kinda guy ( not knocking anyone who is either - each to his own). Thats why I didn't just slap the trans in the box ..not my style. Even if life had given me the time or opportunity to work on it, I'll most likely still be researching. So this is a competely new situation for me and i'll certainly need the advice and help of people "better" than me. When i do this I want it done right and do the speakers justice.....

these PS series Trans just seem to want to go into a 250 box, it feels natural somehow......and i think it would be exciting to take 2 great GT designs and put them together. To repeat myself from other threads, the pS series as it is ( stereo - stacked ) beats almost all other speakers, even those costly MUCH more..it's really amazing.


L250: 400Hz, 1.5kHz, 5kHz @ 90dB sensitivity
PS stack: 130Hz, 650Hz, 3.2kHz @ 91dB sensitivity

in many ways we're comparing apples to oranges here....nice review Dome..very nice...

JBLnsince1959
06-17-2007, 07:14 AM
it's Sunday morning and everyone is still asleep here in the house so I have a few minutes to play....Since Dome "reopened" this thread and it has casued me to dust off those parts of my brain about the project, I'll use this opportunity to use this thread for general brain storming..if anyone cares to add suggestions feel free...

In another post I mentioned the mission statment, now I guess is the time to discuss the project itself in general( In a top-down design method)

1. put the PS series transducers into 250 boxes ( given in mission statement)
2. Bi-amp between the LE14H-3 and 908Ti ( affirmed by Giskard)
3. I have 2 2235's in custom boxes that I'll use for the VLF, that should free up the LE14H-3 from the lower Freqs and give us more flexiblity with tuning the 250 box

well, I can hear my lady and mother moving around upstairs so it's time to switch hats and do the "family" thing...

BTW way...Happy Fathers Day guys...:applaud:

MJC
06-17-2007, 07:44 AM
One thing to keep in mind when building the CC networks is to build a separate card for each transducer, which is what I did on my L212s. In that case, I mounted one on the left side, one on the right side and the third mounted vertically across the rear opening of the 212 box. That helps to eliminate any cross talk.
The guy in Reno, I mentioned earlier, even went further by mounting each card right next to each transducer, in the speakers he designed.
Being the EE that he is, he also had calculated the lengths of ALL the wire used in the XO, including the wires going from the XOs to the speaker terminals.

4313B
06-17-2007, 08:25 AM
The guy in Reno, I mentioned earlier, even went further by mounting each card right next to each transducer, in the speakers he designed. Yeah but those things had stray magnetic fields so I wouldn't put the inductors too close to them, especially the 112H.

MJC
06-17-2007, 09:43 AM
Yeah but those things had stray magnetic fields so I wouldn't put the inductors too close to them, especially the 112H.
Of coarse you know how the original XO was mounted in the 212. That is where I put mine, two of the three, to each side in the upper section. I don't have any in the mid-bass section.
Although in the PT800, the card is mounted to the bottom, inside the mid-bass section. But completely different driver. And I doubt there is enough room for three cards for a CC network.

JBLnsince1959
06-17-2007, 11:22 AM
Well, I have a few minutes free so I'll complete what I was going to say in post #41. Might as well write down my musings for later reference and give people a chance to know where I'm at( and provide a structure should anyone post).....The main questions I have are more general and structual in nature ( staying with the top-down approach)

The only thing I've decided on at this point is that each of the 800 trans will have their own box and will be optimized to eliminate as much vibration as possible and reasonable from
1. Internal vibs
2. External from the 250 box
3. Baffle

the questions I find I have take the shape of:

1. Best tuning of the 250 box, taking into consideration the external 2235 subs

2. Crossover:
A. Best freq crossover for the LE14H-3 and subs
B. Best freq and slope for the active bi-amp between the Le14H-3 and ti908. If we can use the same 130 freq that's used now great, but if there's something better once their in the 250 box OK
C. Can we use the same basic crossover design in the 800 ( CC'ed of course)

3. Baffle..
A. In keeeping with the 250 philosophy of time alignment and placement of the trans, how does PS series line-up on the baffle as it is. It may be easier to just over-lay another baffle on the one there ( double box so to speak) to line everything up. This could also make it easier to place the trans on the baffle and eliminate cutting up the old one. It would also allow for a stiffer baffle and the opportunity to get fancy in eliminating vibs.

B. EOS wave guide and tweeter- should it go flush or should we build a box like the standard 250's. I'm not to sure of the characteristics and nature of the EOS wave guide ( Ok, I know what it does - BUT I don't know the math)

3. Should we place a covering on the baffle like the one that's there and on the XPL 250 and if so what would be the best material.

well, that's where I'm at. When I get the time, those are the questions I have so far as to the basic design. If anyone has an answer or two much appreciated

take care

Hey Dome, thanks for opening this back up. You know when I first saw you reply to this, I had forgotten it was my thread and I didn't look at it at first ( the reasion for my delay in answering)

Robh3606
06-17-2007, 02:30 PM
Just looking over your project. Looks like fun!! Bet it will kick some butt when your done.:D My thoughts on using the Le-14H-3 with 2235 subs??? In that volume the 14's can give you some very impressive low end. I also think the 14's are a better sounding transducer and you may be better off just tuning them for extended bass and forget about the 2235's. Unless you go the B380 with a BX-63 you will not be gaining any more extended lowend and with the group delay in that set up I think the 14's are the way to go.

What I would do is try both ways and see what works best for you. I have LE-14H-3 in my active set-up being broken in as subs. They are in 4 cubic ft and are really impressive in that volume.

Rob:)

MJC
06-17-2007, 04:58 PM
JBLnsince1959,
After 3 years, I don't remember if you bought any SUB1500s, but if you did, that is what I would use for my subs (and I do, with my PT800's) and forget the le14-3, and the 2235's. If the SUB1500's were good enough for Revel, they're good enough for the PT800's.
And bi-amp them with a Crown K2.

JBLnsince1959
06-17-2007, 07:36 PM
Just looking over your project. Looks like fun!! Bet it will kick some butt when your done.:D My thoughts on using the Le-14H-3 with 2235 subs??? In that volume the 14's can give you some very impressive low end. I also think the 14's are a better sounding transducer and you may be better off just tuning them for extended bass and forget about the 2235's. Unless you go the B380 with a BX-63 you will not be gaining any more extended lowend and with the group delay in that set up I think the 14's are the way to go.

What I would do is try both ways and see what works best for you. I have LE-14H-3 in my active set-up being broken in as subs. They are in 4 cubic ft and are really impressive in that volume.

Rob:)

Thanks for the tip Rob. yes, the 2235's may be over kill or just not needed. My thinking was to take the lower ( 40 - 60) freq off off the LE14H-3 in the hope that maybe it would make the LE14H-3 a little cleaner and tighter in it's freq range ( 40-60 to 130). It was mostly to do as you mentioned with the B380 with a BX-6 ( only with two of them)

I'm not real big on blasting bass anyway.... Mostly I'm just brainstorming and thinking out loud..also, I've got two 2235 subs in storage waiting to see day light again. For certain I'll test things out before anythings really written in stone;)

BTW, what are your subs connected too. Since I haven't been on the forum a whole lot lately I may have missed your current complete setup...

JBLnsince1959
06-17-2007, 07:40 PM
JBLnsince1959,
After 3 years, I don't remember if you bought any SUB1500s, but if you did, that is what I would use for my subs (and I do, with my PT800's) and forget the le14-3, and the 2235's. If the SUB1500's were good enough for Revel, they're good enough for the PT800's.
And bi-amp them with a Crown K2.

No, I didn't buy a sub1500...

read my clarified mission statement below- so no can do on forgetting the LE14H-3, it's part of the description...

I'm not really looking for a sub, I was just thinking to relieve the 14 of the lower duties( see post above to Rob and new post below)

I used a K2 with my 2235's and it was sweet( and might pull it out again if i use the 2235's). However, for the LE14H-3s I'll use a BIG MAC to match up with my MC402 ( used on the 800 part)to keep the sound the same..

JBLnsince1959
06-18-2007, 05:09 AM
after re-reading Robs and MJC's reply I realized that in my haste to write, I may have been too general in my general statements ( mission statement and project outline) and people may not have a clear understanding of what I'm planning to do or exactly what my intent is ( My Bad)

so for the sake of clarification I'll rewrite those.....

Mission statement ( clarified)
to take the tansducers (LE14H-3, 908Ti,904Ti, TM025) from the PS Series Stack (PT800 and PS1400 ) and place them in 250 boxes.

Project Outline ( clarified)
1. Place transducers from the PS Series STACK into a 250 box ( given in mission satatement)

2. Bi-amp between the LE14H-3 and 908Ti ( affirmed by Giskard)

3. 2235 subs nixed

I'll most likely start the project for real around Sept to Oct of 2007 ( research and calculations) HOWEVER, it has been over 35 years since I've attemped a DIY project of this complexity so I'll need all the help and advise I can get. I do NOT have the knowledge and experience of Giskard, Rob, Widget, Zilch and the rest of the LHF gang in system design so a lot of learning is my first step. Any help, particularly with the tuning and crossover considerations would be greatly appreciated.

this thread can be used for brain storming if anyone wishes to contibute, once I start this for real I'll create a thread in the DIY forum

Thanks to all who have posted in this thread and shown an interest....:bouncy:

MJC - I'll keep your suggestions about the crossover in mind...very interesting ( In my haste I missed that earlier)

to be continued....

spkrman57
06-18-2007, 07:22 AM
After hearing LE14H-1's myself I have to say the 2235's would not really be necessary.

While the 2235's have more output, the LE14's have a more "pitch-perfect" response that did not leave me feeling the need for more re-inforcement on the bottom end.

Ron

JBLnsince1959
06-18-2007, 07:46 AM
Thanks Ron:

well, that's three people advising me against it so forget the 2235's for now. I'll revise my project outline and focus only on the PS/250 setup.
I've got two 2235 subs in custom made boxes just sitting in storage..maybe I'll have to sell them...


BTW..did you get the E130's finished and hooked up, I may have missed that

spkrman57
06-18-2007, 12:44 PM
Thanks Ron:

well, that's three people advising me against it so forget the 2235's for now. I'll revise my project outline and focus only on the PS/250 setup.
I've got two 2235 subs in custom made boxes just sitting in storage..maybe I'll have to sell them...


BTW..did you get the E130's finished and hooked up, I may have missed that

E130 in 100hz Edgarhorn is not best solution. but running them now as no time to play with anything else. I posted to my "Edgarhorn" thread just the other day.

Ron

JBLnsince1959
06-18-2007, 02:18 PM
Ron:

I'll look for the thread and see what you posted. Frankly I've been too busy to really pay attention to very much here. Hell, I even forgot that this was my thread when Dome reopened it. Now that's sad:p...

Well, I never was going to get rid of the LE14H-3, what I was thinking was to use the 2235 sub boxes to take the VLF (somewhere around 40 to 60 and below)and retune the 250 box to make the LE14H-3 behave more as a midbass speaker so to speak...but that's on the back burner.

I'll look up your thread tonight when i get chance..

Next time I'm in Ohio I'll plan more time to hang around and hopefully Catz and I won't be having "discussions":rotfl:

spkrman57
06-18-2007, 03:21 PM
I'm sure you have more than one system laying around!:p

Ron

4313B
06-18-2007, 04:34 PM
make the LE14H-3 behave more as a midbass speaker so to speak...Cut the moving mass in half and maybe so...

JBLnsince1959
06-19-2007, 04:37 AM
Cut the moving mass in half and maybe so...


which half do i cut off of the cone - the left or the right?:rotfl:

seriously tho, this project is a good time for me to dust off some old books and buy new ones so I can learn more about design. I learn best from doing a project. That way I can make every mistake and learn from them. That's why I'm not in too big a hurry ( also, I've got a business to run with some serious deadlines coming due)

Glad i'm using this thread for brain stroming so you guys can keep me straight;)

JBLnsince1959
06-19-2007, 04:41 AM
I'm sure you have more than one system laying around!:p

Ron


Not really, they were built some time ago to go with my 4430's which I sold to Audiobeer a few years ago. Once i'm done with this project I do want to get back into horns. Those subs just don't fit anything I have in mind.

spkrman57
06-19-2007, 06:20 AM
I'm not really looking for a sub, I was just thinking to relieve the 14 of the lower duties( see post above to Rob and new post below)

I used a K2 with my 2235's and it was sweet( and might pull it out again if i use the 2235's). However, for the LE14H-3s I'll use a BIG MAC to match up with my MC402 ( used on the 800 part)to keep the sound the same..

For myself, I found the LE14H-1 to be a superior woofer to the 2235H as far as the tonal qualites. It will not match the total output of the 2235H, but I think you will not need any help on the bottom end with just the LE14H-1!

Ron

audiophile.1963
07-03-2007, 11:36 AM
This is a reply of JBL L250. The woodworker is the same of the first Italian Sonus Faber and the components are:
woofer 2231h
mid-bass 2118h
mid-high 2105h
tweeter 2403h (the best tweeter of JBL of all times)
wood 30mm block walnut
... what do you think about my personal italian L250?
Ciao
Giuseppe

Storm
07-03-2007, 01:32 PM
Very nice!

What was the total cost to produce those?

-Storm

;)

Titanium Dome
07-05-2007, 05:02 PM
May we see them with the grilles off?

gerard
07-22-2007, 07:02 AM
If you go here, you can get a TM025F7 Ti 1" dome for under $20. This may be a better application than the PT800 tweeter and EOS Waveguide. It basically has a built-in waveguide, though it's non-EOS. You could always adapt it for your purposes, while keeping your PT800 tweeters intact.

http://www.amazon.com/s?ie=UTF8&rh=n%3A281407%2Cp_4%3AAudax&page=1


I have the 035 Ti Tweeter on my 250 Clones .
Could the TM025F7 / SAN SPEAK 2904/7001 / SCAN SPEAK 2904/7000 ( very nice looking and expensive ) or 076 / 077 could make some improvment ? .And of course wich of those ones could be better ? :o:

Gerard

Ian Mackenzie
07-22-2007, 07:44 PM
Giuseppe,

Excellent work,

Did you re work the original passive crossover or design your own?

If you have finalised the system I would like to have a got at it or something very similar.

Ian

Fangio
07-23-2007, 11:52 PM
May we see them with the grilles off?
:yes: please

JBLnsince1959
07-24-2007, 09:43 AM
May we see them with the grilles off?

Giuseppe,

Did you re work the original passive crossover or design your own?

If you have finalised the system I would like to have a got at it or something very similar.

Ian

yes, more information please...are they the same size as the regular 250's, what are they tuned at, crossovers etc...more..more please:D

audiophile.1963
07-25-2007, 09:49 AM
Thanks for your compliments!
I built this pair of L250 in 1993 but I have not the crossover plan because It was assebled by another person. I will send you other pictures of my L250 (I must purchase a digital camera) and I would to see if it is possible to have more informations about the crossover.
Ciao
Giuseppe

JBLnsince1959
09-15-2007, 04:26 PM
Hey Dome.......

In all your research on tweeters did you every find any tech sheets for the TMo25 or TM025F7 Ti

I may be buying the TM025F7 Ti for testing

thanks

MJC
09-15-2007, 06:55 PM
Hey Dome.......

In all your research on tweeters did you every find any tech sheets for the TMo25 or TM025F7 Ti

I may be buying the TM025F7 Ti for testing

thanks
I found this sheet, if it does you any good

Titanium Dome
09-15-2007, 08:40 PM
Hey Dome.......

In all your research on tweeters did you every find any tech sheets for the TMo25 or TM025F7 Ti

I may be buying the TM025F7 Ti for testing

thanks

Start with post 916 of the Performance Series thread

http://www.audioheritage.org/vbulletin/showthread.php?p=170114&highlight=TM025#post170114

Titanium Dome
09-15-2007, 08:44 PM
Here's the main Audax tech sheet page with all the TM025 variants.

http://www.audax.fr/audaxdoc.htm

You'll find MJC's linked PDF there as well as all the others.

JBL 4645
09-16-2007, 12:04 AM
Not sure it's like a rough woven fabric....spkrman57 may be able to shed more light on that. It is not flush but is glued on, so it sticks out.

the tweeter hole will fit a 35tia flush mounted perfectly ( not sure what was meant to be there) and the mid-range will fit a 93 perfectly according to spkrman57..


My guess is its something to do with reducing the mid and high frequency reflections on the front baffle.

JBLnsince1959
09-16-2007, 05:14 AM
My guess is its something to do with reducing the mid and high frequency reflections on the front baffle.


yes, exactly....it's that and the lack of the tweeter housing that makes people think of the XPL250( that and the transducer cutouts, back panel etc). Dome was just wondering what it was composed of and how it was put on..

JBLnsince1959
09-16-2007, 06:02 AM
Thanks MJC and Dome....

I thought you had found something Dome, but then trying to remember where it's at on the forum is somethimes a challenge.

Wish the tweeter and waveguide was still available, wouldn't mind frying one if they were easily replaced

thanks again.

MJC
09-16-2007, 08:21 AM
Like Dome mentioned in the PS thread, you could always buy a pair of L810 surround speakers and harvest the EOS waveguides. The tweeters can be separated from the EOS if you wanted to use different tweeters.

Titanium Dome
09-16-2007, 08:30 AM
Here are some TM025 tweeters (in different Waveguides and in cabinets with woofers and networks):

http://cgi.ebay.com/JBL-S26-Studio-Series-Bookshelf-Speakers-NO-RESERVE_W0QQitemZ190151933133QQihZ009QQcategoryZ14 991QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

http://cgi.ebay.com/JBL-S38-STUDIO-SERIES-175-WATT-3-Way-SPEAKERS-BLACK_W0QQitemZ140157799425QQihZ004QQcategoryZ1499 1QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

JBLnsince1959
09-16-2007, 09:44 AM
Thanks guys...the S26 looks like the best candidate....Of course the top curve would have to be cut off and smoothed down...The nice thing about that over the S38 or even the waveguide that comes with the PS series is that the plate ( once cut) can be sunk and the top made flush with the top of the baffle. This should allow less diffractions over all, one would think. One thing I've always wondered about is the "ring" around the EOS waveguide

This is really an excerise in reducing edge and tranducer diffractions, reflections and enclosure vibrations, and if possible to time align the transducers.

As I've thought about this it really all starts at the top with the tweeter...as i said earlier in post 31...


the 250 boxes with their height raises ( excuse the pun) some interesting design considerations for the tweeter .


for example, as we all know the 250/250Ti enclosures have the tweeter housing which aligns the tweeter on a better axis since it's so high. This of course would produce more diffractions (info was confirmed this week )

Interesting tho, the XPL250 prototype does not have this housing. Of course with the XPL series, reducing diffractions was a major design issue and a housing would undo the general design most likely. One wonders how the XPL250 got around the tweeter axis situation, if indeed it did.

When I go putting the PS series transducers into the 250 box I'll be facing the same issues, but this could be more complicated as the EOS waveguide introduces a new set of issues. Unfortunately I've not found any information as to the exact dispersion nature of the EOS waveguide. My concern tho is NOT with the horizonal axis but with the vertical axis, there are only three cases here.
1. the dispersion is "widen" more than normal ( but not as much as the horizonal)
2. It stayed the same
3. It narrowed the vertical dispersion

number 1 would help us ( but how much who knows); number 2 leaves us at ground zero, or the same place as before; number 3 would take us two steps back so to speak.

Interestingly, the European speakers, the Ti5000 and and TL260 have the tweeters flush, but then again, they are not as tall as the 250, nor do i know the angle of the baffle. I'm looking for more exact information about them. It would be nice to find out how tall they are and at what height the tweeters are at.

IF push came to shove, I could always cut off the bottom of the 250 enclosure to drop the tweeter down and if needed extent out the lower back of the 250 box to add volumn.

well, we'll see what happens, :hmm: I think's it time to go get some chips and dip for the game..

JBLnsince1959
09-16-2007, 02:34 PM
The tweeters can be separated from the EOS if you wanted to use different tweeters.


Maybe some time down the road..however, in the beginning I need to keep it as simple as possible by using the same transducers. Using the same transducers reduces any need for major re-design work with the crossovers. I'm going to have enough trouble as it is......I'm not a Giskard

spkrman57
09-17-2007, 11:55 AM
....I'm not a Giskard

Nor am I unfortunately!

Ron

JBLnsince1959
11-17-2007, 07:33 AM
Just a note to let my friends, those people who have shown an interest in this project and to those who have taken time from their busy lives to help..( much appreicated, thanks)

the project has to be put off again:o:

Unfortunately my lady had some NEW problems starting 4 or 5 weeks ago and now she has to go back into the hospital for another operation the 28th of this month. ( she had two operations in August) I've chosen to just spend my time with her, not be selfish and just do my suff ( which I can easily do - ha)


I haven't on here much because of this...so if i'm not back soon...wish all of you a great holiday season..

enjoy the sounds.......

take care
rick

Robh3606
11-17-2007, 08:30 AM
Hello Rick

Hope all goes well with your lady.

Rob:)

Rolf
11-17-2007, 08:26 PM
Rick!

Your friends here in Norway wish you and your wife, and other family the best.

Don't take any trouble in advance. (hope I got this right)

We love you.

Ruth& Rolf in Norway.

JBLnsince1959
11-19-2007, 07:51 PM
thanks guys, much appreciated...you've seen me before and you've seen Whit of course...but never her...well here we are, all dressed up and no where to go...

jblsound
12-26-2008, 07:01 AM
Thanks guys...This is really an excerise in reducing edge and tranducer diffractions, reflections and enclosure vibrations, and if possible to time align the transducers.

As I've thought about this it really all starts at the top with the tweeter...as i said earlier in post 31...

for example, as we all know the 250/250Ti enclosures have the tweeter housing which aligns the tweeter on a better axis since it's so high. This of course would produce more diffractions (info was confirmed this week )

Interesting tho, the XPL250 prototype does not have this housing. Of course with the XPL series, reducing diffractions was a major design issue and a housing would undo the general design most likely. One wonders how the XPL250 got around the tweeter axis situation, if indeed it did.

When I go putting the PS series transducers into the 250 box I'll be facing the same issues, but this could be more complicated as the EOS waveguide introduces a new set of issues. Unfortunately I've not found any information as to the exact dispersion nature of the EOS waveguide. My concern tho is NOT with the horizonal axis but with the vertical axis, there are only three cases here.
1. the dispersion is "widen" more than normal ( but not as much as the horizonal)
2. It stayed the same
3. It narrowed the vertical dispersion

number 1 would help us ( but how much who knows); number 2 leaves us at ground zero, or the same place as before; number 3 would take us two steps back so to speak.

IF push came to shove, I could always cut off the bottom of the 250 enclosure to drop the tweeter down and if needed extent out the lower back of the 250 box to add volumn.

well, we'll see what happens, :hmm: I think's it time to go get some chips and dip for the game..
I just looked at the TL 260, its 47" tall, is that about the same as the 250?
In comparision, my PT800/SUB1500 stack is 46.75" with the tweeter @ 42.5". Not sure how that compares with the PT800/PS1400 stack.

Of coarse the TL 260 uses drivers more like the Studio L series, that being Polyplas.
And the array is different from the 250; being 3/4" mylar, 1" Ti, 4" poly, 6" poly, 12" poly.
The tweeters are in the waveguides w/o the baffle offset.
Not sure, but I think the use of the waveguides eliminates any diffractions, as they control the radiating pattern.

JBLnsince1959
12-26-2008, 07:32 AM
I just looked at the TL 260, its 47" tall, is that about the same as the 250?
In comparision, my PT800/SUB1500 stack is 46.75" with the tweeter @ 42.5". Not sure how that compares with the PT800/PS1400 stack.

Of coarse the TL 260 uses drivers more like the Studio L series, that being Polyplas.
And the array is different from the 250; being 3/4" mylar, 1" Ti, 4" poly, 6" poly, 12" poly.
The tweeters are in the waveguides w/o the baffle offset.
Not sure, but I think the use of the waveguides eliminates any diffractions, as they control the radiating pattern.

To be honest, I've forgotten most of the details, I'll have to re-read my notes on this. As I've said before personal matters ( and business) has consumed most of my time and thinking over the last 2 years.

First thing I'll do when I get serious on this is to do some "real" numbers so we know exactly what we are dealing with. So far it's mostly just been me "Thinking out loud" on the forum and doing some half-ass quicky stuff.

When I'm doing this for real, there will be a new thread in DIY forum. Who knows, maybe someone will beat me to it and save me all the design work ( ha)

thanks for the interest...:wave:

rick

hjames
12-26-2008, 01:38 PM
thanks guys, much appreciated...you've seen me before and you've seen Whit of course...but never her...well here we are, all dressed up and no where to go...

Nice to see you both - great picture!
Hope all the problems have resolved themselves and hope she is doing better!
Speakers is speakers, but family ... is all important!

JBLnsince1959
12-26-2008, 01:53 PM
Nice to see you both - great picture!
Hope all the problems have resolved themselves and hope she is doing better!
Speakers is speakers, but family ... is all important!

Thanks.. it means a lot. Yes, she's all better now - so that means she can now tell me what to do ( ha);)

It's been a rocky ride for a long time, even Whit( My GS) had some operations the last year. Hopefully I can get back into some form of a normal life here. I have to admit, my quota of JBL'n is next to zero for a long time and my ears are feeling deprived... not mention the many projects that have been set aside for myself and other people.

all the best and thanks again