2214H question

[Boss96]

I hope I'm not beating a dead horse but like I posted previously I find it hard to believe I am bottoming out these woofers with my 100wpc receiver. At this point I have my EQ set to flat, the only EQ I am using now is the loudness compensation on the receiver and that's it. Even so, at about 1/2 volume with the right music I still hear the voice coils hit the magnet occasionally. Is this normal for this woofer?
I removed both of them and looked at the spider assembly, it looks like the spider is a little bit sunken in when looking parallel to the magnet. I would guess perhaps a little less than 1/8". Both look the same. I am guessing the surrounds have been replaced at some point, they are attached behind the cone like they are supposed to be. It's just hard to believe they can't handle the power or have such a limited suspension travel.
Any thoughts?
Thanks,
Bob

[Zilch]

Originally posted by Boss96
It's just hard to believe they can't handle the power or have such a limited suspension travel.
Any thoughts?The wrong surrounds, perhaps? Take 'em in and have them checked....

[Mr. Widget]

Originally posted by Boss96
...I am bottoming out these woofers with my 100wpc receiver. ... I am using now is the loudness compensation on the receiver...at about 1/2 volume ...I still hear the voice coils hit the magnet occasionally.

100 watts is plenty.

Loudness compensation can add a significant amount of extra bass energy.

Most receivers are designed so that they are putting out full power between 12:00 and 1:00 on the rotation. 12:00 being "half way" is actually very near the maximum and by adding a loudness contour you may actually be clipping your amp.

Without a subsonic filter it is relatively easy to exceed Xmax (bottoming) with a woofer if you are asking it to reproduce frequencies below the tuned frequency of the cabinet.

Widget

[Boss96]

Originally posted by Mr. Widget
100 watts is plenty.

Loudness compensation can add a significant amount of extra bass energy.

Most receivers are designed so that they are putting out full power between 12:00 and 1:00 on the rotation. 12:00 being "half way" is actually very near the maximum and by adding a loudness contour you may actually be clipping your amp.

Without a subsonic filter it is relatively easy to exceed Xmax (bottoming) with a woofer if you are asking it to reproduce frequencies below the tuned frequency of the cabinet.

Widget

Thanks for the quick replies:) Widget, I understand the amp may be clipping but how could that cause the cone to bottom out? I realize the loudness contour can drive the amp to clipping even sooner at low frequencies but even so, clipping should not matter "mechanically" as far as the woofer is concerned. I had some other woofers (12") before and they simply did not bottom out regardless of the volume on the same amp. The sound would distort, naturally, but that was it. And these were much cheaper woofers with stamped frames, smaller voice coils, and similar surrounds.
Frustrating..
Bob
Oh, forgot to mention, as far as subsonics go, on this relatively new receiver, I do not have a subsonic filter and I'm not using a turntable anyway. But, I did use my EQ to reduce (from flat) signals below 45hz and they would still bottom out. Seems to be in the 60hz range. I would think the box it tuned in the 30-40hz range which should greatly reduce the cone excursion in that range and even help a little up to the 60hz range.

[Robh3606]

When amps clip strange stuff happens. The amp helps control the woofers cone motion. When you clip this all goes out the window you loose that control and can have what amounts to DC pulses mixed in. Needles to say it is not a good thing. Does it happens with the loudness switch off???

Rob:)

[Boss96]

I'll try it without the loudness comp. but I suppose it will not happen as easily. The only thing about that is they just don't sound good without at least some bass added no matter where I sit or place the speakers. I realize that for some people tone controls are a no-no, but that seems to require a perfect room, placement, and perfect source material.
I will say that these speakers generally sound very good with just the loudness comp, something that is "new" to me compared to other speakers I have had. But with no bass added at all they just are too "thin" to me.
On monday I'm going to see if there are any local JBL dealers in town and bring one for them to see. Maybe sometime in the past they were reconed or repaired incorrectly.
Bob

[Alex Lancaster]

Boss:

Try plugging the port with a sock, if it still does it, Your amp is crazy.

[Boss96]

A sock??:rotfl: I guess I could try that one but would'nt that negate the tuning of the port and the "limiting" of the cone excursion at the tuned frequency and therefore make the problem worse?
Hmm,
Bob

[Robh3606]

Could you post a picture of one of the woofers??

Rob:)

[Boss96]

Originally posted by Robh3606
Could you post a picture of one of the woofers??

Rob:)
Sorry, no camera, will have to borrow one and post it when I can.
Bob

[DavidF]

Do both woofers seem to be the same with this problem?

If so, can you try another amp? You should not use the loudness equalization circuit under high power use with any amp. This will likely cause problems on both the amp side and the speaker side. The 2214s can take a lot of clean power and tempt you to keep upping the power. This may be pushing the amp to current levels where it is not linear, especially with the low end signal boosted.

If not, does the surround on the offender appear concentric, that is it bunched up on one side and seem stretched on the opposite side? Perhaps a sloppy surround repair job.

Do you have the enclosures out in the room or near a wall? You will pick up some mid-bass oomph with them near the wall.

Overall, a lack of bass may be somewhat of an illusion. The L100T has a generally flat response that may SEEM lacking compared to another system with bass emphasis.

If all else fails, take them to a local JBL service center and ask them to run a series of test tones through them to verify the problem is in the speaker(s).

David F

[Boss96]

Surrounds look even, I have done surrounds on speakers myself a few times and know how they can get messed up. Both speakers do the same thing also.
I have another amp at work I can try that has the same power rating I think ( a big Yamaha), I also have a small Hafler power amp I could try with the preamp outs from the current receiver but it is only 60 wpc so it may not be a valid test.
Speakers are against the wall about 6" away from the port.
You guys have me really wondering about the amp though...
Bob

[Zilch]

Few "dealers" are gonna be able to tell if there's anything wrong with the drivers, or if so, what.

You want your nearest JBL Pro Service Center, found from the JBL Pro website, if you want them "checked out."

[Zilch]

Wimpy bass and bottoming out. Donald mentions similar in his LE14A thread. Never bottomed out 2214H's in 4425's, tho I've run them pretty hard on occasion....

What are the symptoms of partial demagnetization? Does the voice coil run away because there's no damping?

I'm not sayin' that's what's going on here; merely asking the question that someone having experience with it might know....

[scott fitlin]

What I have always been told about a woofer with a weak alnico magnet, is that when power is applied to the woofer it will just move forward, and stay leaning forward. Rather than pushing outwards and quickly pulling back!

But, in my experience, some vintage woofers just dont handle very low frequency very well! It is driver dependent, and I had such an experience. We used to use the JBL E-155-8 as the 18,s here, and in the `70,s it was fine! As we moved into the 80,s and the bass in music got heavier, the E155,s would sometimes make a popping sound with a recording with a deep strong bass note. This was the reason for us switching to the 2240H. Now the 2240,s didnt have as much upper bass attack as the 155,s, but the bass was deeper sounding . But, you can pound the 2240,s and they dont bottom, like the E-155,s did! I mean, with some recordings in the 80,s that had a very punchy midbass, but little deep bass, you could push the amps driving the E155,s into clip with no audible problems, but a recording that had deep bass could make the woofers pop easily!

We found it to be more frequency dependent than anything else!

[Boss96]

Well, this is what I did today. I used the Pioneer as a pre-amp and used a smal Adcom 60wpc power amp I have and also used the EQ. So far it seems to work well, I have the loudness turned off but did add some low end with the EQ (3-6db from what I can tell) and they haven't bottomed out yet. Then again I have not tried too hard to get them to do that as I don't want to damage them. Basically I can drive the power amp up to the point where the clipping indicators flash occasionally and the speakers sound fine.
That also happens to be pretty loud:D
I think perhaps the woofers just can't take 100 watts at certain freqencies but overall if I sit in the sweet spot in my living room the bass is very good now.
Bob

[Robh3606]

Well that's good news have a cold one while you listen! I have my XPL'S up and running, same woofers.

Rob:cheers:

[Mr. Widget]

Originally posted by Boss96

I think perhaps the woofers just can't take 100 watts at certain freqencies...


Maybe... I would bet it is the receiver that is the problem. I bet you would have no problem with a 100watt Adcom.

Widget

[DavidF]

Originally posted by Boss96
Basically I can drive the power amp up to the point where the clipping indicators flash occasionally and the speakers sound fine.
That also happens to be pretty loud:D
I think perhaps the woofers just can't take 100 watts at certain freqencies ...


_______________________________________

Bob, from what you are saying above, you seem to need more power, not less. JBLs thrive on a good supply of dynamic power headroom and the 2214 is no different.

I do not know how Pioneer rates their amplifiers, but there is good chance that the Adcom is actually more powerful than the Pioneer despite the difference in rated power.

David F

[Boss96]

Thanks for all the help/suggestions guys, I really appreciate it.
I'm in the electronic repair business and come across audio equipment fairly often and that is how I ended up with the Pioneer and Adcom and just about all the other stuff I have. At this point unless I come across a more powerful amp I think I will leave it alone as going from 60 watts to 100 watts won't make a noticable difference in SPL anyway, but if I do find something else (a Crown DC300 maybe?) you can bet I will let you know what I find:)
The only thing I would like to have now is a traditional loudness contour that boosts the bass at low listening levels but gradually goes away as you increase the level. I'm pretty sure a Yamaha receiver I have sitting at work has that ability and may try it. I have a feeling the only other way to get that is to get a more "vintage" amp/receiver but they don't have remote controls from that time period:( I'm too lazy to get up and adjust the volume:cool:
Now maybe I could get a second pair of L100T's, an amp with about 250wpc and then I could try to break some windows (and REALLY annoy the wife)...:D
Bob

[4313B]

What's the model number on this 100 W Receiver?

I've used strapped Adcom GFA-555's on L100T's without issue.

"going from 60 watts to 100 watts won't make a noticable difference in SPL"

Yeah but that's actually a bad argument. The extra power yields greater headroom.

[Boss96]

Pioneer VSX-9900S. I "think" it was near the top of the line for that model year. Has pre-amp outs for all channels, etc, and is pretty heavy for a surround unit. It does have an impedance selector in back, set to high/normal, if that makes any difference. Adcom is GFA535II, both of these I got for free.
Bob

[4313B]

The Adcom GFA535II is a nice little amp with something like 3 dB of headroom.

[Boss96]

A little update, I spoke to a jbl authorized reconer today, the person I spoke to said he has had that problem before with the 2214h. He felt that reconing them would be a waste of money as he had done that before and it did not help. The spider being slightly "down" like I described before was also considered normal.
Bob

[Robh3606]

You know you might want to give that impedence switch a try. Switch it to low and see if that improves things at all.

Rob:)

[lfh]

Originally posted by Boss96
The spider being slightly "down" like I described before was also considered normal.
Bob

Really? This is most interesting! I bought a pair of 2214H:s yesterday for my "baby S22" project, and they are sagging quite a bit. I thought this was a typical case of "storage disease", but maybe there's hope for those cone assemblies after all. (I was thinking of desparate measures such as shimming the (re-)foam, trying to "preload" the cone, but perhaps that's just nonsense. In any case my basses will seldom see more than 1 W, so a slight offset shouldn't be the end of the world. :hmm: )

[Boss96]

If they are sagging "quite a bit" then I would think you need to repair them. Mine were a little less than 1/8" which was considered normal. I found a few places that would recone them for about $120 ea.
Bob

[Donald]

Zilch,

>>What are the symptoms of partial demagnetization? Does the voice coil run away because there's no damping?


That is what I think I am seeing. At a certain volume level the cone seems uncontrolled. Using my Carver 0.5t I can get louder before it happens. Which could mean I am approaching clipping in both amps. Time for a 200-300 watt/channel amp. :-)

[Zilch]

Originally posted by Donald
Time for a 200-300 watt/channel amp. :-) JBL 6260, or a pair of 6230's. Watch for 'em on eBay....

http://www.jblpro.com/pub/obsolete/6200ser.pdf

[4313B]

"At a certain volume level the cone seems uncontrolled."

That's your amp. Get an amp that can dump some current. Your amp should drive your loudspeakers, not the other way around.

[Boss96]

Well, here is an update, I posted about getting a big Peavey amp to drive these with and even though I had some input sensitivity problems I was able to try it out. Sure enough, the woofers bottom out fairly easily on kick drums, etc. So there is no misunderstanding, I was not able to drive the Peavey very high with the regular stereo pre-amp I had so I was nowhere near the limit of the amp. It looks like the little Adcom is all these woofers can take.

That's not to say I don't like the speakers, sitting in the sweet spot with the right music sounds great, better than any other speaker I have had. I'm just surprised that JBL would build these with a 3" voice coil and huge magnet but not enable them to have much excursion. Maybe the newer stuff (I'm thinking S312 ?) work better?
Bob

[Don C]

I am wondering about this, because my XPLs have the same woofers (I think) and I have never bottomed them, not even when blasting Pat Travers. Are you using vinyl as your source? That would do it.

[Boss96]

Nope, either CD or DVD. In fact I was using Steely Dans 2 against nature DVD. Great sound quality. I have heard of others using pretty big amps with these, maybe they use absoulutely no bass or EQ and can get away with it. I added about 3db in the 60-90 hz range and that kills them. They just don't seem to have enough excursion. I've read about "stuffing" the ports but that makes no sense at all, tuned ports should reduce excursion at the tuned frequency and closing off the port would just reduce the bass output. Of course below the tuning freq. the excursion is worse.

I have other speakers that are similar, 12" woofer, etc, and they have no problems with the same input levels but they don't sound as good:cool:
Bob

[Robh3606]

This has me scrathing my head too. I use them in my XPL clones and have never even come close to bottoming them??!! That's driving them biamped with a strapped Crown that can pump out over 300 watts into them. No signs or sounds of distress at all from them??? Can't figure this one out unless you have some kind of subsonic garbage getting in there somehow??? Two Against Nature Hmm which songs and where?? I have it too Great DVD!

Rob:)

[johnaec]

Could it be Boss96 just considers really loud a normal listening level? Many would consider what I perceive as "normal" to be real loud to them. I'm not saying my ears are bad - I just like "live" listening levels on occasion...

John :band:

[Boss96]

This has me scrathing my head too. I use them in my XPL clones and have never even come close to bottoming them??!! That's driving them biamped with a strapped Crown that can pump out over 300 watts into them. No signs or sounds of distress at all from them??? Can't figure this one out unless you have some kind of subsonic garbage getting in there somehow??? Two Against Nature Hmm which songs and where?? I have it too Great DVD!

Rob:)
Josie, Babalon Sister, etc. I would love to try out a different set of speakers with the same woofer and see how they do.
Loud? I guess I might like things loud..I doubt that's the issue though. I do have a home made sub with 2 12's in it, if I really wanted to complicate things I could use the big amp for the sub and limit the low's to the JBL's or...get a really big passive crossover for the sub and run them both together.
I'll keep an eye out for another set of JBL's, maybe I can find something that works better for me setup. Even a second set of L100T's would be nice, just run 4 of them.
Bob

[Boss96]

Well, here's another update:D

I brought the drivers to a friend who does speaker repairs, I use him in my business when I need to buy surrounds, etc. He looked at them and said the spiders are indeed weak, he showed me a big 15" woofer he had reconed and the spider was actually pushed out a little bit compared to mine which are sunken in somewhat. He will be replacing the spider and will see if the voice coil can be adjusted outward a little to decrease the chance of the VC hitting the magnet under large excursions. I realize I am modifying these as opposed to just getting original JBL recone kits but I will try it this way first and see how they turn out. If they don't seem right I can have them reconed by a local JBL dealer for about $100 ea. (dealer cost) with original JBL parts.
Bob