L100T re-foamed

[annamarykahn]

well, i completed re-foaming the 2214h surrounds, not as difficult as i feared, re-inserted into the cabinet and tuned to my fav fm station, didn't crank them up until after letting them cure overnight

wow, didn't know/expect these to go down so low with so much authority, very nice

the only thing i don't like is the crappy enclosure. will probably make a new one. the previous owner must have a couple too much to drink and decided to paint them black, ... didn't even bother to remove the drivers or mask them ... but i won't complain i got them for free minus one 2214h. the surrounds had rotted a while back and he made his own, ... with duct tape ... (probably made red green proud ) i'm guessing this was probably done the same time as the paint job. got another 2214h off ebay with rotted surrounds that i re-foamed as well

wondering if anyone has any recommendations for a different dimensioned cabinet, with the same volume, obviously?

got me thinking, wouldn't these would be good in a home theater?

anyone have any recommendations for a sub to go with these?

any recommendations for a center channel, or just go without?

oh, i also have surrounds that came from a theater. don't remember their model number, using them in a warehouse area at work. would they be suitable? they're kind of ugly big black things.

i better quit, now, starting to ramble on ... and ... on

regards,

annamarykahn

[bakes837]

Congrats on bringing them back to life!

The cabinets are OK, could probably stand some crossbracing, but the veneer is like paper and probably the weakest part of the speaker. If you're at all handy with spray adhesive and an Exacto knife re-veneering is not an awful job. W/r/t new cabinets, I'd tend to keep them the same size/shape.

I'm using mine as the front channel on my home theater and they work very very well for that purpose; sonically effective and the cabinet height puts the mids close to seated ear level. I have a 4311 that's being retrofitted and tweaked into a 4412-alike for a center, but I usually have the center channel phantomed on the L100ts. The surrounds - give the big black boxes a try! If nothing else they'll serve until you can find something with similar voicing to the 100s.

Sub-wise, because the L100ts go down so deep, you can get away with a true sub that covers the bottom octave and a half, maybe 16-50 Hz, and crosses over at that point. I've found that such a sub (I did a symmetrically loaded bandpass box per Margerand's Speaker Builder article) does a good job on LFE and on music with substantial bass (pipe organ, etc), but for other music I usually keep it turned off.

Enjoy!

[annamarykahn]

if i duplicate the internal volume, can I move the vent out to the front, or side, (bottom? off the floor obviously) or is this not recommended as the vent dimensions were designed to have a certain "phase response" (180 degrees out of phase of the woofer?) so that it will be in phase at the listening position, or does it not matter where the vent is located?

thanks

amk

[John Hodgson]

I refoamed its little brother the L80t. I love the sound. I agree with the gentleman who said you need a real subwoofer to do any good. I tried a lesser one and the L80t trounced it.
The port position does not determine the 180 degree phase swing.
John H

[4343]

if i duplicate the internal volume, can I move the vent out to the front, or side, (bottom? off the floor obviously) or is this not recommended as the vent dimensions were designed to have a certain "phase response" (180 degrees out of phase of the woofer?) so that it will be in phase at the listening position, or does it not matter where the vent is located?

thanks

amk

Vent location is not critical, as long as it does not open right at the back of the woofer cone. That can cause noises. (Upper ranges of the woofer back-wave that normally get absorbed by the fiberglass stuffing.)

I prefer front ports myself, so the rear ports on my L100T's are sort of a pain to deal with. (It means that you cannot position close to a wall, have to have some space.)

On mine, one of the cardboard tubes was all crinkled up on the inside, so I bought some 4" flared ports off the 'bay. They were too short, so I trimmed them to be half as long as they need to be, and used two per box. Some PVC cement holds them together. I read somewhere (some link Zilch posted somewhere...) that the distortion caused by a port goes down with the flared port, and that both ends must be flared for the lowest distortion. Even lower distortion is possible if the inside end of the port is mounted on a baffle. So I found a way to put one in the bottom of the box, sort of as a cross-brace going side to side about midway between the front and the back. It's about 14" X 14" made of 3/4" mdf. I figured that it would have to be made in two pieces to get it in the finished box, so I cut 2 square pieces, then cut them in half. After cutting them in half I glued the center only back together so that I could cut a round hole for the port. Since only the center was glued, I ended up with a round piece and two rectangles with a half circle missing on one side. One of these went in the bottom and was glued tight. Meanwhile, the rear port hole was too small for the flared ports, so I had to cut a plug to tap into the hole to give me a center for my Jasper jig to turn on. I then cut the larger size hole in the rear, and mounted the flared port, half from the back, half from inside, with the PVC cement in the middle. Lastly the second half of the inner baffle went in and was glued down over the inside flared end.

I think they sound a little tighter in the lowest registers now, with all the work, they'd better!

So anyway, this has been a long way of saying, if you do redo the boxes, put the port on the front, and use flared ends, inside and out, and think about putting a brace in that forms a baffle for the inside end of the port tube. (Plus others to tie the front to the back as well.)

Oh, and put the mid and tweeter on one box to the left, and one to the right. (Mirror image.)

The front baffle dimensions are a really good starting point for a new box, because if you change them that may upset the frequency response of the speaker. At least in theory the crossover is designed with those dimensions in mind. Moving the mid and tweeter from the left side to the right wont matter, as long as the dimensions from each side and from the top and bottom of each driver are the same as the other one. If you really want to change the baffle dimensions, I'd build one box and compare the sound to the original box before building the second...

[opimax]

My 250s have their port directly behind the woofer, wondwe why? I think I have heard the ports don't belong there before too, I am confused.

Mark

[4343]

My 250s have their port directly behind the woofer, wonder why? I think I have heard the ports don't belong there before too, I am confused.

Mark

Probably the only place it would fit. Or the cooling effect of fresh air for the woofer vent?
With a 4-way, there's not a lot of midrange being fed to the woofer anyway. A 2-way, or 3-way could be another story.

[Siamac]

I just find some nice JBL L100T GI and refoamed them.
Does somebody know what GI at the End means.
I know TI means Titan, but GI?

[hjames]

Well, I was told the S model were the ones sold in Military base Exchange and such ... from what I heard, they usually have vinyl grained cabinets, not veneer - but yours look like the veneer mine have (L100T with T3 networks) . Never heard of a GI version before.

I just find some nice JBL L100T GI and refoamed them.
Does somebody know what GI at the End means.
I know TI means Titan, but GI?