2435's on Ebay???

[DJ Vincenzo]

all of the sudden in the past 45 days or so, ive seen about 20 of these drivers for sale for only about $200 each.....what gives? first i thought u had to be a vertec owner to get them and second they retail for 1400 new each. Do u think they are all a scam with generic diaphragms in them. The lastest one hear says it was rebiult with jbl factory parts....pffft...bulls***. The replacement diaphragm cost 700$....

http://cgi.ebay.com/JBL-PRO-2435HPL-1-5-EXIT-SERIES-COMPRESSION-DRIVER_W0QQitemZ320078324031QQihZ011QQcategoryZ470 92QQrdZ1QQcmdZViewItem

[DJ Vincenzo]

is there a way to see if it really has the Beryllium cone in them?

[Robh3606]

there a way to see if it really has the Beryllium cone in them?

Yes open them. However I don't recommend it if you are not familiar with changeing diaphrams and don't have a way to check the realignment of the diaphram. It's real easy to see and every one I have purchased has been the real deal. I purchased from both of the most active sellers and had good results with them.

Rob:)

[4313B]

It is possible that is was rebuild with JBL factory parts. People do take advantage of the five year warranty period.

I have no idea why we are seeing a flood of these really cheap 2435's. Maybe they were on a container ship that ran aground and they got looted. I guess all I have to say about it is grab a spare pair.

[X_X]

I have no idea why we are seeing a flood of these really cheap 2435's. Maybe they were on a container ship that ran aground and they got looted. I guess all I have to say about it is grab a spare pair.

I have some insight (having done some live sound apps with the vertec). A rodie told me once that the fluid in them gets destroyed after being abused on the road. JBL doesn't replace the fluid. Bad fluid=bad sound. A person's experience with these drivers can be very undesirable if they aren't "right". Live sound guys know when their shelf life has expired, and they dump them. It's still a great deal, because ferro fluid is very inexpensive and easy to replace.

Giskard,

I am finishing up my first crossover later this weekend. Thanks again for your help! I'll send you a picture.

Nathan.

[4313B]

Thanks Nathan. :)

Just be sure not to do a full refill guys. JBL only does a partial fill with that ferrofluid.

I can't remember the specific type of ferrofluid they use. I have the information somewhere and will try to dig it out at some point.

[Thom]

I was under the impression that ferrofluid was for cooling. perhaps I assumed "only". I'd say that I know next to nothing about ferrofluid but that is probably more than I know. I've seen it available, from the magnet guy on Ebay I think< is their more than one. Is it a term that is rather broad? How easy is it to get into trouble? Is there somewhere I should look instead of posting all of these questions here? Thank you in advance.

[John W]

I have some insight (having done some live sound apps with the vertec). A rodie told me once that the fluid in them gets destroyed after being abused on the road. JBL doesn't replace the fluid. Bad fluid=bad sound. A person's experience with these drivers can be very undesirable if they aren't "right". Live sound guys know when their shelf life has expired, and they dump them. It's still a great deal, because ferro fluid is very inexpensive and easy to replace.


This doesn't add up. If this negatively affects the sound, is cheap and easy to replace, why doesn't JBL do it?
My question is similar to Thom’s. Is it ok to just remove the fluid? I don’t think the power handling reduction will be a problem at home.

[matsj]

How much do you pay for these drivers ?
HMMM I live in the wrong area :( i don´t se these in Sweden.

mats

[X_X]

This doesn't add up. If this negatively affects the sound, is cheap and easy to replace, why doesn't JBL do it?
My question is similar to Thom’s. Is it ok to just remove the fluid? I don’t think the power handling reduction will be a problem at home.

My information is purely second hand. I could be wrong. I was simply sharing what I have been told.

I can say this about them (first hand): Topping off the fluid is one thing- completely removing it (and replacing it) is a more involved task. I guess they (JBL) are cutting some corners?? :dont-know Speculation.

The 2435 is silver and attracts the heat of the sun. A vertec array set out in an amphitheater and blasting high SPL's is bound to have it's fluid break down into base ingredients (goo!)- Just like oil in a car's engine.

I don't see any reason for the ferro fluid to exist in a home environment. I see your thinking, and I agree. Why not just remove it completely!? Anyone see a reason for it to be there in the home environment??

[Robh3606]

Topping off the fluid is one thing- completely removing it (and replacing it) is a more involved task. I guess they (JBL) are cutting some corners??

Hello Nathan

I have completely replaced the fluid in a pair and it's no big deal at all. All you need is a stiff absorbant paper and comes right out. It stays right in the gap. It would take a tech about 15 minutes to open the driver, wick it out and replace the ferrofluid.Then you reassemble and sweep. They would rather dump them than do this??? Then purchase new replacement drivers?? Well then again if they are replaced under warranty??? Hey man keep them coming!! I am certainly happy with mine.

Rob:)

[4313B]

I can't remember the specific type of ferrofluid they use. I have the information somewhere and will try to dig it out at some point.That was fast!

"APGS38N is the grade of Ferrofluid. 100ul is the amount." - courtesy of D.B. at JBL

http://www.ferrotec.com/products/ferrofluid/audio/apgS.php

[Zilch]

The lastest one hear says it was rebiult with jbl factory parts....pffft...bulls***. The replacement diaphragm cost 700$....The listing says "Refurbished."

I have had a pair of them refurbished by the JBL factory. The performance measurements before and after are documented in Widget's Horn and Driver Comparison thread here, along with my recommendations.

The factory disassembled them, cleaned the gaps, and recharged with new ferrofluid. They came back perfectly matched. The diaphragms were apparently correct and original.

I have not been able to get reasonable answers from either major vendor as to the history of the drivers they sell. While their listings say "New, never used," it's apparent from the condition of the drivers upon receipt that they have been previously mounted, at least. They do not come in JBL packaging, or with any JBL documentation.

Another source tells me that, with heavy use, heat can irreversibly alter the viscosity of ferrofluid, and whatever damping it provides, as well. Tour providers may be changing these out as "routine" maintenance. That's just speculation on my part, tho.

In any case, these are a bargain, and an opportunity to DIY with some of JBL's best drivers. Ideas as to how to use them appear in several threads in these forums.

[4313B]

I hope Giskard can resolve the ferrofluid issues for us. :yes:Done. See post #12.

PM sent Zilch. Please edit your post. Thanks :)

[4313B]

You guys are fast! Ferrotec just told me they have had a few emails very recently. :rotfl:

Ok, so who wants to go in on the $100 minimum order?

[John W]

I got a reply:

Min purchase is $100.00 on a Master Card or Visa. The APG S38n is $ 1.20 per ml.
We do have this fluid in stock. You would need to order 84 ml.



1000ul = 1ml right?

I'm in for maybe a third of an order? Anyone else want to go in on this together?

[Robh3606]

Hello John

You didn't tell them that it was for a speaker. You can purchase 'speaker kits" for $4 each with a $100 minumum or 25 kits and get them already dispensed into the proper recharge volume. I am ordering 25 kits. I need 10 and will Ebay or sell you guys the rest.

Rob:)

[Zilch]

1000ul = 1ml right?Yes. The 84 ml is enough to do 840 charges. 100ul is just a couple of drops. I doubt I would ever use $10 worth.

However it ultimately splits out, count me in. :thmbsup:

[John W]

Hello John

You didn't tell them that it was for a speaker. You can purchase 'speaker kits" for $4 each with a $100 minumum or 25 kits and get them already dispensed into the proper recharge volume. I am ordering 25 kits. I need 10 and will Ebay or sell you guys the rest.

Rob:)

Way to go Rob. :D
I don't think I need it in bulk.

[hjames]

Did you see the clip on Rocketboom last year about the artist who was working with ferrofluid ... its early in the video show - may 10 -30 seconds in ... but shows a dynamic videoclip of moving ferrofluid:
http://www.rocketboom.com/vlog/archives/2006/01/rb_06_jan_23.html

The original video was on a Japanese site - the links changed, but there are some images here as well:

http://www.kodama.hc.uec.ac.jp/protrudeflow/works/index.html (http://www.kodama.hc.uec.ac.jp/protrudeflow/works/index.html)

[Zilch]

Way COOL, Heather.

Thank you for finding those!! :thmbsup:

[X_X]

Hello Nathan

I have completely replaced the fluid in a pair and it's no big deal at all. All you need is a stiff absorbant paper and comes right out. It stays right in the gap. It would take a tech about 15 minutes to open the driver, wick it out and replace the ferrofluid.Then you reassemble and sweep. They would rather dump them than do this??? Then purchase new replacement drivers?? Well then again if they are replaced under warranty??? Hey man keep them coming!! I am certainly happy with mine.

Rob:)


Shhhhh-! I was trying to keep the market value low until I stock up!

Seriously, that's cool. Wicking... I'll try that next time. It sure beats pouring it all over the place...not that I did that...I'm just saying...oh foget it! :banghead:

[Zilch]

http://audioheritage.org/vbulletin/showthread.php?p=63323#post63323

eBay 2435s on PT-H1010, this filter:

http://audioheritage.org/vbulletin/showthread.php?p=146690#post146690

M552 highpass @ 1 kHz.

Expanded scale view, second.

Conclusion: two, in particular, would likely benefit from cleaning and recharging with fresh ferrofluid. They play within +/- 1.5 dB of each other as purchased, however. #5 and #6 were refurbished by the factory over a year ago, #5 being down ~5 dB @ 1.8 kHz prior to doing that.

[4313B]

I've updated the Technical Reference Section and included notes.

2435H (http://audioheritage.org/vbulletin/showthread.php?t=14369)

[Robh3606]

The Ferro Fluid has been ordered and the packets will to be shipped tommorow with 3 bulk 10 ml containers to follow up in a couple of weeks. Would you believe they ran out of the stuff for another order.

Rob:)

[Thom]

Shhhhh-! I was trying to keep the market value low until I stock up!

Seriously, that's cool. Wicking... I'll try that next time. It sure beats pouring it all over the place...not that I did that...I'm just saying...oh foget it! :banghead:

We understand. You read about it somewhere.

[Thom]

I read the warning about a full charge vs the factory using 1/2 charge. Are the consequences known?

What are the likely consequences of crossing this driver too low ( 500 - 600 ) at reasonable power and with a horn that will couple at those frequencies?

(google spell check is a wonderful thing but I sure have learned to accidentally properly spell a lot of words I'd never heard of )

I find the polarity puzzling. I thought that at a certain date all drivers that existed wound continue to move the cone out with + to black and anything created after that date would move the cone out with + red or with compression drivers is + pressure considered moving the cone in. No attempt at an argument here I was just surprised when I red the polarity but way down deep I think I may have heard something about compression drivers being different and being the origins of JBL's polarity marking system in the first place. I'm sure the answer is a lot simpler than my convoluted question. Thank you.

[Zilch]

Here's six more eBay 2435HPLs, this time on PT-F1010, 'cause I sent my PT-H's to Heather for "evaluation." ;)

These are running on the "Gauntlet" filter, with M553 highpass @1 kHz.

http://audioheritage.org/vbulletin/showthread.php?p=146690#post146690

Clearly #15 requires cleaning and ferrofluid recharge; it's behaving like the one I sent back to JBL for refurbishing. #11 would likely benefit too.

SO, that's 2/16 (12.5%) = "Service required" so far, and 5/16 (31.25%) total "Service advised."

Expanded (5 dB/division) vertical scale, bottom:

[Zilch]

And six more:

Filter's a little different from previous runs, per request.

2/6 apparently need reconditioning, so the rate remains ~33%.

[Yes, "bright...." ;) ]

[timc]

Hi.

Does anyone still have some of this fluid i can buy? I need for 2 drivers.


-Tim