An experiment that seems to have worked- converting 2213H to 128H w/ aftermarket kit

[edgewound]

Since JBL closed its production facility in Northbridge I image there are plenty of JBL people "available" out there that could start something around this... (and maybe even the tooling?...)

R$D is still done here. Large production is done with equipment that has been moved south.

[doyall]

Please don't go down this road. ...

Seems as though even in light of objectivity many will continue to paint with a broad brush. It surely looks like as long as some/most aftermarket parts are unacceptable, all aftermarket parts will be damned by some without the benefit of testing. I thank you for sharing your findings and hope it will continue. I feel confident that in the not too distant future those very people who now protest will come to appreciate it as well.

[4313B]

It surely looks like as long as some/most aftermarket parts are unacceptable, all aftermarket parts will be damned by some without the benefit of testing.

I think it depends on where someone draws the line.

For example, JBL has a room full of reference standard loudspeaker systems with rotted foams. As far as JBL is concerned they are unrepairable (even with their own recone kits) whereas one of us would buy some Rick Cobb foams, refoam them and go on using them.

I personally like this quote:

I'll say it again regarding aftermarket parts. It better be damn close/identical to OEM in every regard for it to be JBL acceptable. Outside of that it's just another cast frame speaker with potential to be great.

JBL knew what they were doing when they engineered their transducers (taken in context of the applicable eras) and they've never been real thrilled with wildly varying standards. They've always liked the "close tolerance" gig.

While I personally have little interest in aftermarket kits for JBL transducers I can see where such activities would fit into the DIY section of this forum. It can be quite enjoyable to mix and match this and that for the sheer fun of it.

[speakerdave]

I'm with edge on this. Support the remaining kits. Devising and publicizing less costly substitutes will only hasten their demise.

[Mr. Widget]

I'm with edge on this. Support the remaining kits. Devising and publicizing less costly substitutes will only hasten their demise.

I hadn't thought about it in those terms, but that is a good point. If there is a market for factory kits and the bean counters can see them as a revenue stream, they are more likely to continue producing them. We may all be disappointed that Harman in their infinite wisdom have pulled production from Northridge, but I think most of us still feel that the JBL "factory" kits are still best available in most cases.


Widget

[ivica]

I think it depends on where someone draws the line.

For example, JBL has a room full of reference standard loudspeaker systems with rotted foams. As far as JBL is concerned they are unrepairable (even with their own recone kits) whereas one of us would buy some Rick Cobb foams, refoam them and go on using them.

I personally like this quote:

I'll say it again regarding aftermarket parts. It better be damn close/identical to OEM in every regard for it to be JBL acceptable. Outside of that it's just another cast frame speaker with potential to be great.

JBL knew what they were doing when they engineered their transducers (taken in context of the applicable eras) and they've never been real thrilled with wildly varying standards. They've always liked the "close tolerance" gig.
.

As I can understand
"..loudspeaker systems with rotted foams. As far as JBL is concerned they are unrepairable (even with their own recone kits)...."
mean that they can not be repaired under ANY CIRCUMSTANCES, so JBL recone kits are present here just to 'enhance money income".
I can not understand what kind of technology has been applied 30 or 40 years ago, that is not possible to be applied today in order to produce "appropriated" foam or cone, especially if the price of OEM parts is concerned.
That would be understandable if ALL type of drivers are available as spares ( for exchange) with "understandable price", but now it seems that for an example C8R2245 (not to mention driver 2245H), would not be available now or soon. On the other side, we are aware, that the "operation life" of studio monitor is not 10 or 20 years, especially if their drivers are 'power reinforcement ready divers".

So I wonder if now ."..JBL KNOW ..." .concerning : "...JBL knew what they were doing when they engineered their transducers..."
May be some amount "of light" would come from "www.jblselenium.com"

[4313B]

As I can understand

It isn't real hard to understand. Even JBL with their industry leading tolerances can't return an engineering standard system to spec. It can't be done.

I'm with edge on this. Support the remaining kits. Devising and publicizing less costly substitutes will only hasten their demise.

I'm not so sure about that. There are all different kinds of people out there and some of them will pony up the cost of going legit and some of them are going to go with the cheapest solution because they just don't care.

[ivica]

It isn't real hard to understand. Even JBL with their industry leading tolerances can't return an engineering standard system to spec. It can't be done.

I can understand that the other parts were gone out, not the foam "only", but if the "basket assembly" is in the technical tolerance (mechanical, magnet ,etc), it is difficult to me to understand that "the cone assembly (with the coil+wires...)" is impossible to produce, even if appropriated "re-cone kit" is available. Does that mean that the mentioned re-cone kit is NOT exact replica of the original "cone assembly"?
If that is"the case", what are we buying now for not so small amount of money? Is it "the best EXPECT-ABLE solution" for such amount?

[Robh3606]

I think we are in a semantics battle so to speak. We have engineering standards where I work. Usually a unit is tested and selected by engineering to be the standard/baseline unit.

Once a unit is picked to be a standard it never gets a finger laid on it again by manufacturing. It becomes a standard until the end of it's life. If we were making speakers and foam fell apart that would be the EOL for that standard. There is no going back.

That doesn't mean or imply there is anything wrong with the re-cone kits. It's just a point of view. From a strict engineering discipline point of view it makes sense. At least to me.

Rob

[4313B]

Thanks Rob

If that is"the case", what are we buying now for not so small amount of money? Is it "the best EXPECT-ABLE solution" for such amount?

Think of it as buying 5% tolerance instead of 25% tolerance.

Obviously someone in Japan is going to buy the 5% tolerance. And someone in the midwest that found a JBL at a second hand shop or in the dumpster might opt for the 25% tolerance.

[timc]

I think we are in a semantics battle so to speak. We have engineering standards where I work. Usually a unit is tested and selected by engineering to be the standard/baseline unit.

Once a unit is picked to be a standard it never gets a finger laid on it again by manufacturing. It becomes a standard until the end of it's life. If we were making speakers and foam fell apart that would be the EOL for that standard. There is no going back.

That doesn't mean or imply there is anything wrong with the re-cone kits. It's just a point of view. From a strict engineering discipline point of view it makes sense. At least to me.

Rob

I fully agree on this.

The problem if you repair a reference product, is that it might be identical, or it might not. The chance of failure is way higher than the chance for sucsess. So better to get a new reference, with identical specs to the one that died.

[ivica]

I fully agree on this.

The problem if you repair a reference product, is that it might be identical, or it might not. The chance of failure is way higher than the chance for sucsess. So better to get a new reference, with identical specs to the one that died.

Every think is, for me understandable, only if the production process of "reference unit (units)" is different then the production of the "normal (ordinary)" units.

But my point is not to deal with "reference units", I just wonder, what we, as a ordinary customers can get after "re-coning" JBL units with OEM re-cone kits. Can we expect "acceptable" driver (in accordance to the factory specification) or something that is +/- xx % of unit JBL specification, or only "a good luck can help".

[timc]

But my point is not to deal with "reference units", I just wonder, what we, as a ordinary customers can get after "re-coning" JBL units with OEM re-cone kits. Can we expect "acceptable" driver (in accordance to the factory specification) or something that is +/- xx % of unit JBL specification, or only "a good luck can help".

But that is what me and others are trying to say. You simply don't know. You can hit it spot on, or you can get something that is way off.

The whole point of a reference is that all production should be withing x% of it. If we then do a repair to the reference and skew the spec with y%, then we would also move the production y% further away from the intended target.

JBL has the reference for their drivers. Others don't. Gordon has obviously hit very close to home with his aftermarket purchase, and that is a good thing for him. But can we trust that if we bought 4 recone kits, that they all would perfom exactly similar?

[ivica]

The whole point of a reference is that all production should be withing x% of it. If we then do a repair to the reference and skew the spec with y%, then we would also move the production y% further away from the intended target.

Me, personally, do not expect that reference unit has such purpose, I have been expecting that the such unit is present:
1. in order to confirm that under proposed technology process the production line has possibilities to produce the products of expect-able characteristics with some % of their variation,
2.and if something goes wrong (say more then "technology-expect-able"just produced units do not satisfy the proposed specification) the reference unit is "present" to be "easily" compared to the just produced (not satisfied) pieces, in order to find out what is (are) the reason(s) of such (un-expect-able) behavior.

About reparation reference units: may be for JBL it is cheaper to produce a new reference unit then to repair (foam) on EOL (end-of-life) one.

[doyall]

... But can we trust that if we bought 4 recone kits, that they all would perfom exactly similar?

In light of post #18, the same thing might also be asked of original JBL recone kits.

Thinking back, it seems as though I remember reading at least one post about member reconing a transducer with (presumably) a factory kit and not getting anywhere close to the specified T/S parameters then stating that the reconed transducer was off to eBay.

Which certainly raises the question: When a factory authorized service facility recones a JBL transducer with an original JBL recone kit, does tha factory authorized service facility test the finished product's T/S parameters against the reference standards and if it does and if the finished product does not produce T/S parameters within an acceptable range does JBL furnish another recone kit at no charge and does the factory authorized service center install the second (or third, etc.) recone kit at no charge?