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Royd
10-03-2004, 08:26 PM
I won a pair of L150A cabinets w/crossovers on eBay. I have 044, 044ti, le5-2, le5-5, le5-9, 104h-2, 122A, 123A, 2213, loose drivers. I don't have the passive radiators. Is it possible to install a pair of functional woofers where the passive radiators should go? Can they be wired so that both woofers in each cabinet would work, or is the passive radiator mandatory? Thank you for your assistance.

Robh3606
10-03-2004, 08:31 PM
Well until you get them why not figure out the port needed for that cabinet size and just make a cover plate with a port?? Then you have a functional design where if you try the passives and don't like them you can always go back to just a simple reflex port.

Rob:)

Royd
10-03-2004, 08:39 PM
That sounds like a plan. Since I have so many loose JBL 12" drivers, I was wondering if 2 woofers would be better than 1 woofer and 1 passive radiator. Thank you.


Originally posted by Robh3606
Well until you get them why not figure out the port needed for that cabinet size and just make a cover plate with a port?? Then you have a functional design where if you try the passives and don't like them you can always go back to just a simple reflex port.

Rob:)

Zilch
10-03-2004, 09:40 PM
Originally posted by Royd
Is it possible to install a pair of functional woofers where the passive radiators should go? Yes, BUT,

1) Unless the them woofs are 16 ohm, the impedance gonna be wrong for the crossovers, and,

2) You'll have to cut a port to tune the box and perform the function of the passive radiator.

SO, bad idea probably.

Not gonna hurt anything to try it on an interim basis, tho.

Maybe just use speakers in place of the passives without hooking them up. Tuning will be wrong, but, again, we're talking "interim," no?

Royd
10-03-2004, 09:57 PM
Good point about the 16 ohm requirement. Look like 2 8 ohm woofers will not work. I'll have to shop eBay for the PR300 radiators, or try fashioning my own ports. Thank you.


Originally posted by Zilch
Yes, BUT,

1) Unless the them woofs are 16 ohm, the impedance gonna be wrong for the crossovers, and,

2) You'll have to cut a port to tune the box and perform the function of the passive radiator.

SO, bad idea probably.

Not gonna hurt anything to try it on an interim basis, tho....

GordonW
10-03-2004, 11:46 PM
If you strike out trying to find PR300s to buy, I may be able to build you something functionally equivalent. Since it's a passive, the basket isn't that important... a generic 12" basket would work OK, as long as it'll fit into the cabinet. That, loaded with a JBL-spec 12" cone and spider (like that used to recone a 128H) and set up with the right hardware to allow mass adjustment plates/washers to be installed, should probably work.

That, and the pair of 122A woofers you have, should work OK in those cabinets. The 122A isn't that terribly much functionally different from a 128H (a little more mass on the cone, so it's like a fractional dB less efficient than the 128H)...

For a midrange, I'd be inclined to try the 104H-2. Should be more like the sound of the LE5-12 that was in the later model L150s.

As for tweeters- rather than cutting up the cabinets, I'd be inclined to find someone where you could buy/trade for a pair of 033 or 034 tweeters. But, if you wanted, there's no reason that pair of 044 tweeters shouldn't work- you'd have to turn down the L-pad on the tweeter lower than stock, but it should work.

Regards,
Gordon.

Royd
10-04-2004, 06:31 AM
Thanks for the offer on the passive radiators. I'll be in touch if nothing shows up on eBay. In the meantime, would putting in a woofer without hooking it up work? Thank you.


Originally posted by GordonW
If you strike out trying to find PR300s to buy, I may be able to build you something functionally equivalent. Since it's a passive, the basket isn't that important... a generic 12" basket would work OK, as long as it'll fit into the cabinet. That, loaded with a JBL-spec 12" cone and spider (like that used to recone a 128H) and set up with the right hardware to allow mass adjustment plates/washers to be installed, should probably work.

That, and the pair of 122A woofers you have, should work OK in those cabinets. The 122A isn't that terribly much functionally different from a 128H (a little more mass on the cone, so it's like a fractional dB less efficient than the 128H)...

For a midrange, I'd be inclined to try the 104H-2. Should be more like the sound of the LE5-12 that was in the later model L150s.

As for tweeters- rather than cutting up the cabinets, I'd be inclined to find someone where you could buy/trade for a pair of 033 or 034 tweeters. But, if you wanted, there's no reason that pair of 044 tweeters shouldn't work- you'd have to turn down the L-pad on the tweeter lower than stock, but it should work.

Regards,
Gordon.

Robh3606
10-04-2004, 07:07 AM
It might but you would be much better off tunning the box correctly instead of hit or miss. You really won't know what you have going that way. Do you have software?? All you need to do is plug in the woofer you want to use and then change the box volume to your box size. Then adjust the tunning frequency to see what the response will be.


http://www.linearteam.dk/default.aspx?pageid=winisd


That is a link to WinIsd. It's a free box program you can use to play around with. Your bass drivers are all preloaded all you have to do is select them from the driver database.

Rob:)

Alex Lancaster
10-04-2004, 07:55 AM
Since You have them, I would try the woofer as a PR, tell us how You like it.

Robh3606
10-04-2004, 10:42 AM
OK

Here are the numbers to port. Using 2 2" ports 5.23 long 3.97 Cu Ft. 25Hz

Rob:)

DavidF
10-04-2004, 11:16 AM
The closest match to box and components seems to be the 122A woofer (close to 128H in spec), 104h mid (similar acoustically to LE12), and the 044 tweeter (actual driver). I would not suggest using another woofer, unconnected electrically, as a passive substitute. The mass loading would be too low and would not compliment the bass response without modifying the woofer. A round plate fitted to screw into place over the hole for the passive would work much better, with a vent 4 inches in diameter and 6.5 to 8.5 inches in length. This could easily removed if later you find a pair of original passives or you use another make.

David F

Zilch
10-04-2004, 12:09 PM
What passive network could be connected to the teminals of a speaker substituting for a passive radiator to "tune" it for desired performance? :D

Royd
10-04-2004, 05:00 PM
I'm amazed at the knowledge base here. I really appreciate all the advice from you experts. I'll try the 2nd woofer first as an experiment. If that doesn't sound good, I'll purchase some wood and plastic pipe to fashion the baffle cover and port. I still haven't given up on getting a pair of passive radiators, but I now have other options. Thanks again.

GordonW
10-04-2004, 09:01 PM
Man, actually, you guys are right... the 044 IS the right tweeter. Dunno where I got it in my head from, that it was an 033. No futzing about required- just bolt the 044 in!

As for the PR- does anyone have the cone assembly effective moving mass measurement on a factory PR300? If so, it'd be EASY to duplicate it. As long as the mass and cone area are right, nothing else will matter much...

Regards,
Gordon.

mrbluster
10-06-2004, 06:40 AM
Any thoughts on using one or more Me12OHS drivers in a L150 I have T/S parameters, If someone could cruntch the numbers for me. Also, what about sub dividing the cabinet Ala K2 S5500 and using Two woofers?

Earl K
10-06-2004, 07:36 AM
Hi mrbluster

There are a few people here who can crunch the numbers on the ME120HS.

I'd suggest publishing the ts parameters here in this thread .

If you don't mind me asking, How did you end up with ME120HS woofers ?

Any pictures available ?
( I'd like to determine if the LE120H-1 is a ME120HS with another name .)


<. Earl K

mrbluster
10-06-2004, 08:06 AM
I believe it is an LE120H minus the fancy back cover. I will post more info a little later.

Earl K
10-06-2004, 08:14 AM
Thanks ! <> Earl K

- Now we need a similar picture of the LE120H-1, can anyone helpout here ?

4313B
10-06-2004, 08:21 AM
The ME120HS was used in the S2600
It uses the C8RME120 recone kit

The LE120H was used in one of the newer Ti series
The LE120H-1 was used in the L7
The LE120H-1S was used in the S3S and Citation 5.4
The current recone kit is the C8RLE120-1

Earl K
10-06-2004, 08:29 AM
Hi Giskard

- What other info do you have on these 12" variants ?

- Do you have Ts parameters for the LE120H-1 ?

- Any idea what was the dfference beween the 3 LE120 types ?

Thanks <. Earl K

mrbluster
10-06-2004, 08:43 AM
Correction, I was thinking about an LE125S What can you know about this one?

mrbluster
10-06-2004, 08:48 AM
At one time I had quite a few ME120HS units, and one actually had a second label which was LE125S.
P.S. sorry for the earlier Type-O

Earl K
10-06-2004, 09:21 AM
Originally posted by mrbluster
Correction, ,,,,,,,,,,,an LE125S What can you know about this one?

- The LE125S was the 12" woofer used in the K2 S5500 .


,,,,, ME120HS units, and one actually had a second label which was LE125S.


- Good info to know about the rebadged LE125S being labelled as an ME120HS .


- Did you take the Ts parameters yourself ?


At one time I had quite a few ME120HS units,,,

- Then, I guess I watched your eBay sales . :D - didn't save the info - so your identity is safe . :cool:

- Giskard has posted above that the 2 take different cone kits.

<. Earl K

4313B
10-06-2004, 09:34 AM
The LE125S-12 (the only LE125 variant listed) takes the C12RLE125 kit and it was indeed used in the S5500.

Oh! But for the days of the 124A or 124H! :rotfl:

mrbluster
10-06-2004, 09:36 AM
One of my Ebay customers came up with them( T/S) I will post them this evening along with another picture.

Earl K
10-06-2004, 09:49 AM
Originally posted by mrbluster
One of my Ebay customers came up with them( T/S) I will post them this evening along with another picture.

Okay - Thanks ! :thmbsup:

Could you also provide some DCR readings from your remaining ME120HS woofs .

( there's a bunch of impedance info here that doesn't quite jive - for instance, the published impedance curve for the S2600 shows a woofer with a much lower in-circuit working impedance .

<> Earl K

mrbluster
10-06-2004, 09:50 AM
Had a little time, so here they are. ME120HS

Fs 30.99 Hz
Re 5.51 ohms
Qms 8.04
Qes 0.28
Qts 0.27
Le 1.12 mH
Vas 4.02 cu. ft.
Mms 2.99 oz
Cms 54.47 in/lb
Bl 18.10 tesla
SPLref 92.7 dB "

Let me know what you come up with regarding the L150 or other applications.

Thanks in advance!

mrbluster
10-06-2004, 11:13 AM
ANOTHER PHOTO

mrbluster
10-06-2004, 02:29 PM
What would be the dimensions of the port?

Earl K
10-06-2004, 04:24 PM
Originally posted by mrbluster
What would be the dimensions of the port?

Well, First ; thanks for posting the pictures and the Ts parameters that you were given . They are quite useful.

Now ; You've got some nice woofers there - you should buy some comparable enclosure tuning software. Here's some available from "Parts Express" (http://www.partsexpress.com/webpage.cfm?webpage_id=3&SO=2&&DID=7&CATID=48&ObjectGroup_ID=360) . "Bass Box Pro" is a favourite of users around here. If you are on a Mac like me , then your choices are more limited. TrueAudio (http://www.trueaudio.com/) has MacSpeakerz for the Mac platform . They have a free demo available "here". (http://www.trueaudio.com/mac_demo.htm) There's also some free stuff available ( I can't remember where ). The problem with the free stuff is it doesn't give you any idea of the amount of power you can apply to the system before you "over-excursion" the woofer.


Here's a response study of a single ME120H loaded into a 2 cu' enclosure . It's tuned to 34 hz with a 4" diameter round tube that is about 11.75" long .
Giskards tunings are more accurate than mine - so take these with a grain of salt.

If you get some tuning software, consider making an MTM setup with the bottom box & top box being two different volumes. Look at @ 2.7 cu' for the bottom and 1.3 cu' for the top box( & everything in between ). Play with the tunings. Start with a 31hz tuning for the bottom box and @ 39 or 40 hz for the top box ( & again - everthing in between ) .

Again - Thanks !

<. Earl K:)

mrbluster
10-06-2004, 05:09 PM
Hello, Earl,

Thanks for all of your suggestions. I do have a Mac.

Would you or Giskard be able to provide me with port dimensions if I were to put two of these woofers in my L150 cabinets as Giskard suggested.
(tuned around 30-32 Hz).

I don't know the volume of these cabinets. Perhaps you do? I know they are a lot bigger than the two cubic foot example you sent me.

Again, thanks for all of your useful input. I appreciate it.

Regards,

mrbluster

Earl K
10-07-2004, 04:48 AM
Hi

- I believe on the first page of this thread, Rob states that the volume of the L150 is @ 3.97 cu'.

- A ME120h in 2 cu' can achieve a 31hz tuning with a 4" round port @ 14.7" long . ( this port length varies slightly with the software program used )

<> Earl K

mrbluster
10-07-2004, 07:06 AM
Thanks to Earl and Giskard for your patience. I realize I am all over the place with this project. Let me throw this out. I can restore the L150 with an original 128 and passive unit, or I can use one or more ME120HS drivers as per the previous discussion. I am hoping to tap into you expertise, to avoid experimental "improvements" that ultimately will disappoint. (Such as the many attemps to re-engineer the L65) I realize that some things must be tried in the "real world" to determine there worth or downside, but with the benefit of your years of experience, perhaps I can be directed to put my energy into the most rewarding direction.

Sincerely,
Mrbluster

mrbluster
10-07-2004, 07:30 AM
Black faced, think it is an L150 with 033 HF.

mrbluster
10-07-2004, 07:46 AM
With the ME120HS, (I assume you mean two) how would I wire them?
Mrbluster

mrbluster
10-07-2004, 07:48 AM
Perhaps you are talking about a single with the original Passive?

johnaec
10-07-2004, 07:49 AM
If you recently picked up those empty cabinets off eBay, I believe they were the L150A version, which would mean the crossover is tuned to the 044 HF.

John

mrbluster
10-07-2004, 08:05 AM
RE: Twin ME120HS I am also assuming I will then need an appropriate port? Or could it work sealed?

mrbluster
10-07-2004, 08:41 AM
Thanks, will get back to you when I have something to report. In the meantime If you or anyone else could come-up with the port configuration I would be grateful. If there is potential in this upgrade, I would like to know that I have all the basic info to move forward. My guess is that ME120HS would not be suited to a sealed cabinet.
Regards,
Mrbluster

mrbluster
10-07-2004, 09:22 AM
Point well taken!
Much thanks, Giskard .
I'm out of here as well.

Mrbluster

johnaec
10-07-2004, 07:32 PM
One quick question before you guys bail - are those frames basically the same size as the LE14 series, (with the squared-off baskets), or some other variation that fits in a 12" speaker cutout? :confused:

John

Don C
10-07-2004, 09:06 PM
I hate it when you guys delete part of a thread before I have read it, nothing makes sense.
The speakers shown on the last page look nothing like LE-14s from the back.

Zilch
10-07-2004, 11:26 PM
If those parameters are right, and assuming I entered them correctly, WinISD says two ME120HS in 3.97 cu.ft. box tuned to 32 Hz. wants one 4" port 5.31" long.

It's down 3 dB at 60 Hz, and down 9 dB at 30 Hz, the "knee" occuring just under 40 Hz.

Two of them in a closed box that size are down 3 dB at 95 Hz, and down 9 dB at 45 Hz, not good.

"Optimally flat," a single driver wants a 1 cu.ft. box tuned to 47 Hz. Two drivers want 2.137 cu.ft. tuned the same. Note: WinISD also generates impractical results for Sub1500.

A major problem with the proposed scheme is that, wired either in series or parallel, two of these are not going to match the stock network impedance.

I don't know what's up with this thread, either. Looks like some good stuff got deleted, alas.... :(

Earl K
10-08-2004, 04:55 AM
Hi John


or some other variation that fits in a 12" speaker cutout?

The LE120h is a different woofer from the pictured Me120h . Paragon posted the necessary pictures of one of his LE120h(s) to arrive at that conclusion. Different magnetic assemblies and different gap depth.

The LE120h ( should ) be an evolution to the 128h or 2214h - maybe 2213h . It might be a nice 12" "Project" speaker for the DIYer. Unfortunately, without a JBL published response curve and some Ts parameters - that's still conjecture .

Don / Zilch ;
Re; deleted posts

- Sometimes others wish they just hadn't got involved.
- Myself, I just stop talking, others are more proactive .
- The deletion time-limit of 24hr, gives a form of ownership to the poster that I support .
- People forget they don't "own the library book".

<. Earl K

paragon
10-08-2004, 06:55 AM
LE 120H

paragon
10-08-2004, 06:56 AM
Next

mrbluster
10-08-2004, 07:43 AM
Does anyone still have the post regarding NETWORK "mod" for using two ME120HS in an L150? Would appreciate it if you could repost or send to me.

THANKS ZILCH, for all your input.

MRBLUSTER

mrbluster
10-10-2004, 08:33 AM
Very strange etiquette here. Isn't this forum for "technical help"? No "Library" I know of offers assistance and then withdraws it. I am a little disappointed in this otherwise outstanding Site.

Mrbluster

4313B
10-11-2004, 05:01 AM
Originally posted by mrbluster
Very strange etiquette here. Isn't this forum for "technical help"? No "Library" I know of offers assistance and then withdraws it. I am a little disappointed in this otherwise outstanding Site.

Mrbluster The Library is here (http://lansingheritage.org/).

Posts in a forum can be withdrawn as required/desired. I also deleted several posts I posted yesterday in response to your last post after spending half an hour putting together a few schematics and then getting them in postable form. Why? After further investigation it has been found that none of the components in the L150 or L150A would be able to keep up with dual ME120HS in the midband. If you wish to pursue the endeavor you might wish to look at biamplification. I suppose you could also try something like a 4435-type LF response but that would take a lot of tweeking with large inductor values.

Have you thought of pursuing an MTM design with a compression driver/horn instead?

mrbluster
10-11-2004, 08:18 AM
Giskard, All of your efforts, in this instance and others are truly appreciated. Your contributions have been acknowledged numerous times by the many JBL aficionados on this site including myself.

Please understand that many of us here enjoy and learn from the give and take of the discussion, and even If you can see several moves ahead, there are things to be gained from the process.

Re: the L150's I see now I need to take a different approach . Thanks to all: Giskard, Earl K, Zilch and others for your help.

Regards,
Mrbluster

4313B
10-11-2004, 08:46 AM
Originally posted by mrbluster
Please understand that many of us here enjoy and learn from the give and take of the discussion, and even If you can see several moves ahead, there are things to be gained from the process.Ok. I will endeavor to keep that in mind going forward.

Royd
10-13-2004, 08:57 PM
I picked up the L150A cabinets today. The walnut veneer on the sides looks great. The veneer on the tops have some kind of rubber squares stuck on them than I'm guessing were used under glass tops. The base on one of the cabinets is smashed on one side. I'll have to use some wood glue and filler for repair. I noticed that 28 of the required 30 mounting screws for the drivers are missing. Can someone suggest where I can find replacement screws? Does JBL still have them for sale? Thank you for your help.

Steve Gonzales
10-14-2004, 12:33 AM
Have you tried Speaker City? I went there once and the man who runs it seemed very knowledgeable, he spat out Thiele-Small parameters like no person I've ever talked to. I am no expert but I consider myself to be somewhat informed and this guy made me feel like I was from another planet! I want to say it is in Burbank but could be mistaken. I'll bet you could Google it and find it. I would stick with JBL stuff but if you wanted to experiment with different brand of Passive then you should check them out. I remember seeing some Peerless passives that looked well made and a few others. I had the same problem finding screws for my L222's and when to Buget Bolt in Bakersfield and found the Stock looking ones and then discovered Allen Heads that really are a nice touch. I even found the tapered-head counter sunk type screws in the Allen Heads. I would say the sizes of the machine screws are 8-32 and 10-32's, at least they are in my models and every model I've had before. Goodluck with your L150's!

Steve Gonzales
10-14-2004, 12:51 AM
I think the Allens give it a nice touch.

Steve Gonzales
10-14-2004, 01:13 AM
I have a trustworthy friend in New York that has a clean pair of 122A's if you want to try them. I can set the deal up for you if you are interested, let me know and you can talk to him yourself. By the way Regis has a pair of L150's and seems to know alot about them. He put some 128H's in place of the 122A's and liked the results and also bought some LE5-9's from me for the midranges.

Royd
11-18-2004, 03:04 PM
I was lucky enough to score a pair of PR300's on eBay with bad surrounds. I plan on sending them to OC speaker repair for the refoams. I had already purchased the port tubes and a hole cutting jug from Parts Express and was waiting for a free weekend to begin. I'll post another update when the speakers are ready for prime time.

Scooter
11-23-2004, 03:08 AM
The 2005 Parts Express catalog has two twelve-inch passive radiator types in their Dayton line. Peerless has one too--in the same catalog. Might be worth an on-line peek at the sizes.

Scott

hificanada
10-23-2009, 03:14 PM
Thanks ! <> Earl K

- Now we need a similar picture of the LE120H-1, can anyone helpout here ?

;)Photos of the driver LE120H-1, also another photo of the LE120H-1, in the L7's that I bought new a number of years ago , they are original and have never been replaced.

JeffW
10-23-2009, 03:33 PM
I will post that tonight

It's been 5 years since the request, but maybe they are still interested :)

Earl K
10-24-2009, 08:23 AM
Now we need a similar picture of the LE120H-1, can anyone helpout here ?


I will post that tonight
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=42518&stc=1&d=1256341052

It's been 5 years since the request, but maybe they are still interested :)

- IMHO, it's never too late to contribute to the knowledge base here at LHF .

Thanks >< EarlK