Looky What I just got - Those Darned L200 Cabs (from Aberdeen)

[hjames]

Well, I've got them in place. One needs a bit of brushing and repaint, but that's all external looks stuff - the sound is what I was interested.

Put on a Sinatra remaster - "One for my baby ..."
very nice improvement in detail, with just a hint of harshness at the top ... sibilance

Then we tried Aja - stepped through various tracks hearing nuances in the piano and guitar we hadn't heard. Again, just a hint of harshness in the horns ...

As a last touch, we put on Mark Knopfler - Shangri-La - Boom, Like that ... wow - modern, well done recording .. just stunning.

Got a busy weekend and won't have much listening time - but I can't wait to try out Bill Evans, Lyle Lovette and a ton of other things ...

Haven't opened the drivers so I don't know 'phrams are in there ... but its def a step up from the 2425s that were driving these horns, and they have to be clearer with that extra adapter/reducer out of the way ...

Oh, that's not scratches on the horns or cabinets
- I just didn't oil everything up for the pictures!

[toddalin]

Looks like they were "Rode Hard And Put Up Wet," literally.

[BMWCCA]

Are they defying the law of gravity, or are the drivers resting on the glass tops?

[Mr. Widget]

Looks like they were "Rode Hard And Put Up Wet," literally.

Yep... if they sound great, then.... cool, but I really doubt they will be operating even remotely near spec.

As a matter of course I would order a pair of 2441 diaphragms, yes I know they are expensive, and have them professionally installed. If I was in your area I'd use forum member oldmics... he knows his way around vintage JBLs and will be able to make these right.

Regardless of how they sound now, spending a few hundred dollars and putting them in the hands of a pro will make them sound better.


Widget

[Zilch]

I'd be wanting to try SL diaphragms in those:

8 Ohms = D8R2450SL, $264
16 Ohms = D16R2451SL, $234

[hjames]

I'll have to look into what drivers they have and what I do with them next.

Currently, they are both playing, and between the cost of buying them,
plus the outlay for the Richmond Scottish Festival we just got home from,
I'm not dropping any audio bucks for a bit ...

Oh - and it looks like I have a further answer for the great HK AVR7300 repair conundrum -
but I'll put that in the AVR Frontend thread!!

[Altec Best]

Yep... if they sound great, then.... cool, but I really doubt they will be operating even remotely near spec.

Regardless of how they sound now, spending a few hundred dollars and putting them in the hands of a pro will make them sound better.

Widget

As Widget says.It would be a good idea to have them checked out for peace of mind not to mention lots of pleasure down the road.

It may help in removing some of the harshness you are hearing in the top end with replacing the diaghrams. I think a good cleaning of the gap is a good idea as well.With any driver that has some rust on them. The problem with rust is the driver is creating it's own dirt (Rust) that is magnetic so if it gets near the gap at all,the magnetic field will suck it right down into the gap.


Added: Hey Heather I have used compressed air too.Also use a sticky note folded in half (Use Adhesive on note) too.And be patient it is very hard to clean a dirty gap thoroughly due to the magnetic field grabbing a hold of any metal bits and refusing to let them go not to mention the tiny gap to get anything in there in the first place.So just take your time and do it a half dozen times or more.Alternate between (Comp.Air & Sticky Note)I've had good results this way.Stay at an angle say 45 degrees and try to work it up and out even with the compressed air nozzle,you have to get under and pop it out so to speak. And it doesn't cost anything if you do the work ! Good Luck ! Regards ~ John

[toddalin]

The problem with rust is the driver is creating it's own dirt that is magnetic so if it gets near the gap at all down it goes.

And it never sleeps.

Perhaps your harshness is nothing more than crumbling foam impinging on the diaphragm.

[hjames]

Not much chance to listed to canned music over the weekend -
it was all live on stage near Richmond, and MANY live pipers ...
but after all the traffic driving home today, and after we unpacked everything,
I did sit and play catchup to read some of the Sunday Washington Post.

So I put 3 CDs on to play while I read:

The Blue Nile - Hats (played for 3 songs)
Lyle Lovette - Joshua Judges Ruth (just played track 3)
Mark Knopfler - Get Lucky (played Border Riever and a few others ...)

The Post was the Post, what can I say, but the music was excellent!
I didn't hear the harshness I'd heard on the Sinatra last week ...
Tomorrow I'll swap the two horns and drivers and see if I hear any difference -
I know all the logic and I am not faulting or insulting anyone here, but honestly,
I have no intention of spending upwards of $500 to maybe fine tune what sounds excellent right now.
Especially when we are getting a new furnace and AC installed in the next 2 weeks ...!

Agreed that upping them to 2441 spec and replacing the diaphragms sounds like the right way to go -
but it'll just have to wait - maybe after Christmas, or after my Tax refund in the spring ...

BTW - only one driver has that loose paint and just starting some (exterior) surface rust - the other is perfect looking.

I'd be wanting to try SL diaphragms in those:

8 Ohms = D8R2450SL, $264
16 Ohms = D16R2451SL, $234

Yep... if they sound great, then.... cool, but I really doubt they will be operating even remotely near spec.

As a matter of course I would order a pair of 2441 diaphragms, yes I know they are expensive, and have them professionally installed. If I was in your area I'd use forum member oldmics... he knows his way around vintage JBLs and will be able to make these right.

Regardless of how they sound now, spending a few hundred dollars and putting them in the hands of a pro will make them sound better.

Widget

[pos]

opening them and checking/cleaning the gap will not cost you a thing. You might have to change the foam pad as well, with this advice from 4313B in mind :

Don't use Arlene's glue in these back caps guys. I used the Moyen recone glue in my 2445J's and there weren't any issues.

http://www.audioheritage.org/vbullet...l=1#post283244

http://www.audioheritage.org/vbullet...l=1#post283259

And then you can also apply aquaplas on the diaphragm, wich will give you a D8R2450SL diaphragm (titane, no ribs)

[hjames]

opening them and checking/cleaning the gap will not cost you a thing. You might have to change the foam pad as well, with this advice from 4313B in mind :

http://www.audioheritage.org/vbullet...l=1#post283244

http://www.audioheritage.org/vbullet...l=1#post283259

And then you can also apply aquaplas on the diaphragm, wich will give you a D8R2450SL diaphragm (titane, no ribs)

Awesome advice - thanks! I've got compressed air and can find thin flexible plastic
to clean the gap (Mind the gap??) But where do I get a small bottle of Aquaplas??

[toddalin]

I know all the logic and I am not faulting or insulting anyone here, but honestly,
I have no intention of spending upwards of $500 to maybe fine tune what sounds excellent right now.
Especially when we are getting a new furnace and AC installed in the next 2 weeks ...!

BTW - only one driver has that loose paint and just starting some (exterior) surface rust - the other is perfect looking.

One thing for sure about the LHF, there is no shortage of people who will help you spend your money..., whether you have it or not.

Obviously, it costs nothing/near nothing to check/fix the foam if that's a problem.

If the surface rust is light, try wiping it down with a rag with some WD-40 sprayed on it to both remove the light, easy stuff and help keep it from spreading. If the rust is on the faceplate, remove the diaphragm if necessary and be careful near the gap. (But this may not be a good idea if you intend to repaint it as the WD-40 will resist the paint.)

BTW, I and some other people use folded "Post It" notes to clean the gaps. The bit of sticky holds the dust so you can get it out.

Perhaps the original harshness you hear/heard is somewhere in the recording process and with intent listening, and perhaps a more revealing driver, you are now just first noticing it.

Happens all the time.

[badman]

One thing for sure about the LHF, there is no shortage of people who will help you spend your money..., whether you have it or not.

Obviously, it costs nothing/near nothing to check/fix the foam if that's a problem.

If the surface rust is light, try wiping it down with a rag with some WD-40 sprayed on it to both remove the light, easy stuff and help keep it from spreading. If the rust is on the faceplate, remove the diaphragm if necessary and be careful near the gap. (But this may not be a good idea if you intend to repaint it as the WD-40 will resist the paint.)

BTW, I and some other people use folded "Post It" notes to clean the gaps. The bit of sticky holds the dust so you can get it out.

Perhaps the original harshness you hear/heard is somewhere in the recording process and with intent listening, and perhaps a more revealing driver, you are now just first noticing it.

Happens all the time.

Agree with everything- especially people helping you spend. Check the easy free/cheap stuff first, then proceed to more drastic measures. I've seen people recc recones for a 3mm puncture wound on heavy paper-cone 12" subs. Many things can be fixed with appropo care.

BTW, Todd, I've gotten my JBL (well, JBL drivers) horns together pretty darned nicely, you have some time to roll down the hill for a stopin sometime? PM me

[Mr. Widget]

One thing for sure about the LHF, there is no shortage of people who will help you spend your money..., whether you have it or not.

I sent a pair of JBL 2441 drivers to Northridge back when they used to rebuild drivers there. They had "perfectly fine" original diaphragms. When the techs tested the rebuilt drivers both diaphragms failed the test. I had to spend a few hundred dollars extra if I wanted my drivers to be operating within spec. Now, it is true these 2445 diaphragms are more robust than the aluminum diaphragms, however even under ideal circumstances they are a bit harsh to some ears. I agree that the cost of doing this right isn't trivial, but Mercedes cost more than Dodge and it isn't due merely to marketing and country of origin.


Widget

[hjames]

I sent a pair of JBL 2441 drivers to Northridge back when they used to rebuild drivers there. They had "perfectly fine" original diaphragms. When the techs tested the rebuilt drivers both diaphragms failed the test. I had to spend a few hundred dollars extra if I wanted my drivers to be operating within spec. Now, it is true these 2445 diaphragms are more robust than the aluminum diaphragms, however even under ideal circumstances they are a bit harsh to some ears. I agree that the cost of doing this right isn't trivial, but Mercedes cost more than Dodge and it isn't due merely to marketing and country of origin.


Widget

No, I did not dismiss your comments, its just that can't change the rules of math for you!
The drivers were an off price sale so I'm not complaining about them ... $210 plus shipping seemed like a killer deal!

Otherwise, I'm spend up for the next few months and, no matter what I might like to do,
we're spending roughly $6k on a new furnace and AC the first week of November,
so everything else will have to wait.

Really! No more money, ain't gonna happen, nada ... casho no mucho ... REALLY!