DIY "4345" Project

[eso]

Search MA-15, MA15... here and on eBay.

They used to be available directly from JBL Pro Parts... the part numbers are listed in a number of threads here. They may or may not still be available from JBL... they are regularly available on eBay.


Widget

That's the part. Thanks!




eso

[4313B]

Where does one find the cast aluminum speaker mounting clamps?

I just received 250 of them so they're still available. The JBL Pro part number is 60958.


I managed to get the last two 2122H recone kits available. Pro was out so I checked Consumer and they had just two left. What luck! The next scheduled production run is after the June JBL Manufacturing move to Mexico.

I have all the 3145 network parts now and will start putting them together next weekend. I finished up all the 3155 networks this past weekend.

[dkalsi]

I have all the 3145 network parts now and will start putting them together next weekend.

- I better get started and complete all the steps (re-paint baffles, polyfill, tungoil, etc.).

Really looking forward to your build and the results.

[4313B]

Oops! I forgot about the bi-amp switch. I'm waiting for that to come from Japan. Kenji sourced a bag of good ones. If it doesn't exist he has it made. The guy is simply outstanding.

Greg sent me Paul Bente's DX-1 so I'm going to work up a pair of cards for that too. I already have all those parts and Greg sent me a bag full of the connectors. He likes my 4345 variants.

[JuniorJBL]

I like extra cool goodies!!

[RedCoat23]

I've just acquired some 2420H's with 2307 horns from the 'bay; and I have also got some 2245h's, 2123's and a single 2405H on the way from craigslist.

My question is this; is it worth spending the money to put the D16R2421 diaphragm in to make it a 2421B and similarly, shoulld I have the 2123 reconed as a 2122?
In both cases the existing diaphragm and cone are in good condition.

I still need to build a cabinet and source a network yet, so those are part of the consideration - since the network isn't really interchangeable between the two options - at least that's my understanding.

I've have looked around on the forum and seen comments on either way, but I wonder for those of you that have a standard drivers in your 4345 and those that don't, if facing this choice which way would you go? :dont-know

Best Regards

[dkalsi]

Hi 4313B,

Any updates on the crossovers yet?

Thanks,
D

[4313B]

No, and the list of orders for them is getting longer... Hopefully when Rick gets back from Germany the bi-amp switches will be waiting for him so he can ship them to me.

I really need to get the first pair of bi-amp only networks done quickly because I want my 4345's sold by the end of May. I have to redo the room they are in over the summer.

[4313B]

Guys, I'm waiting on the bi-amp switches... I hope they are up to the task. I'll know more when saeman gets back from Germany.

While I would never use a full passive network in this large of a system the opposition is clearly stacked against me. Everyone wants the full passive option (primarily because most people have the 4344 rather than the 4345). I thought the bi-amp only solution, ala 4350/4355, would be easy to justify. It has been anything but.

[dkalsi]

Guys, I'm waiting on the bi-amp switches... I hope they are up to the task. I'll know more when saeman gets back from Germany.

While I would never use a full passive network in this large of a system the opposition is clearly stacked against me. Everyone wants the full passive option (primarily because most people have the 4344 rather than the 4345). I thought the bi-amp only solution, ala 4350/4355, would be easy to justify. It has been anything but.

Hi 4313B,

This is going to be a really dumb question: but have the schematics for the crossovers been finalized. I personally have no intentions of going the full passive route. I already have an active Ashly crossover and just recently purchased a McIntosh 270wpc solid state amp that I plan to use for bass duty.

In the events the schematics for the bi-amp version have been finalized, could you please post. On the other hand, if you are waiting to build the crossovers and then spend some time tweaking them before you finally settle on the schematics - then I am more than happy to wait. Lastly, could you please confirm that the schematics in progress will accommodate 2440/1 drivers as for a mid-hi? I know there is no such thing as "universal networks", but I remember reading somewhere in this thread that the 2441s may be used in lieu of the 2425/6

Thank you once again for all your efforts.

Cheers,
D

[4313B]

In the events the schematics for the bi-amp version have been finalized, could you please post.

I will after I build a few and get my time out of the effort.

On the other hand, if you are waiting to build the crossovers and then spend some time tweaking them before you finally settle on the schematics - then I am more than happy to wait. Lastly, could you please confirm that the schematics in progress will accommodate 2440/1 drivers as for a mid-hi? I know there is no such thing as "universal networks", but I remember reading somewhere in this thread that the 2441s may be used in lieu of the 2425/6

The network I am building to start with is for the 2421B/2425J/2426J. Since I am using the 2445H-SL I will need to modify my networks accordingly. I think I posted previously that the 2-inch throat driver has a bit more bottom end and a bit less top end so the bandpass will have to be modified accordingly. I have a pair of 2441's that I was also going to build a specific network for but I have lost faith in their Bl factor so I am scraping that option. I'll just pop some D16R2445J diaphragms back into my 2445 cores and use them as a baseline instead. Same difference.

Bo uses EQ so the fact that he has TAD drivers instead of his stock 2421B's won't make any difference. He already has the EQ curve dialed in.

I really want to get through this as quickly as possible because I am sick and tired of JBL and want to move on to something else (The impending manufacturing move to Mexico in June and the last group of folks to get their walking papers as of last Friday pretty much killed the brand for me personally). I have tons of other projects that are much more fun and rewarding to do around both my houses. First is a log cabin playhouse for the kids and I want it done before the end of the summer! Given that I work from 7 AM to 8 PM everday during the week I am hard pressed for time.

[boputnam]

Bo uses EQ so the fact that he has TAD drivers instead of his stock 2421B's won't make any difference. He already has the EQ curve dialed in.

And I'll (re)check it all with the new networks.

First is a log cabin playhouse for the kids and I want it done before the end of the summer!

[eso]

The network I am building to start with is for the 2421B/2425J/2426J...

It seems like there are plenty of 2425J drivers floating around out there at really cheap prices. I've been hunting 2425H units for a project of mine and I come across several pairs of Js for every pair of Hs. I just paid ~$100 for a clean pair of Js needing new diaphrams... easy to replace with H diaphrams. If only I could swap the foilcals out too.

eso

[4313B]

And I'll (re)check it all with the new networks.

I need to look over those curves again and refresh my memory.

[spkrman57]

I have tons of other projects that are much more fun and rewarding to do around both my houses. First is a log cabin playhouse for the kids and I want it done before the end of the summer! Given that I work from 7 AM to 8 PM everday during the week I am hard pressed for time.

You'll appreciate the time with your children!

Ron