DIY 4344 MKII using Beyma TPL-150

[Drummerboy2]

Hi All, I originally wanted to do a 4345 Clone but I decided to try a 4344MKII version first but in a 3 way. I have the 2245's for a 4345 but I will try with the MCM 55-2963's 15" which are supposed to be very close in sound to a JBL 15". I have two pairs of JBL 2123H's and the Beyma TPL-150 is on their way. I have created a xover for these drivers using Xover Pro software and it looks (Graphs) really nice so far and all drivers seem to match up very well. For now I will be using the 15" Knock Down cabinets from Parts Express that I got last week. This should give me a good feel for what this combo of speakers can do. I will be making an enclosure for the 10" to isolate the 10" from the 15" woofers like in the 4344 and will set the Beyma 150 on top of the cab. I ordered the TPL-150 without the horn so I can get a wider dispersion (120 degrees horizontal) than with the horn (80 degrees). Hope this will work out.

I still need to get the 2245H's reformed. Once I get those done I may take a stab at the 4345. But for now I will just stay with the 3 way 15" version.

Any feedback or info is appreciated.

[1audiohack]

Interesting. I am trying to figure out how to not sound cynical, honest.

So, the only thing JBL in this project is a driver (2123) that JBL never used in a home or monitor application. Granted it’s not a big leap from a 2121/2122.

Add to that a knock down box likely not optimized for the woofer and some type of tweeter (I obviously didn’t look it up) without the normally used waveguide? Sorry but to me this resembles a 4344 like a Mustang resembles a Camaro.

The journey can be very rewarding and or very frustrating. There is truly a multi dimensional skillset required along with a real tool list to help navigate through the fog if you want to build anything that approaches something like the 4344.

I don’t know what your skillset is but if you don’t clone an existing design you might be in for a rough ride.

I am all about DIY and I hope you have fun and it sounds great too, really but what you have proposed is far enough diverged from any JBL design as to render useless any helpful comparisons to your design.

Anymore I just can’t imagine doing this without a measurement rig and DSP. Do you have a way to measure the response when they come together?

Barry.

[grumpy]

Looks like fun. Calling it a custom 3-way based around a 2123 mid might help in concept and execution.
Hope your custom crossover included some 4434-like eq/contouring for the mid, which should make
integrating the other drivers a bit simpler (woofer being mostly box driven, tweeter appearing to need
a reasonable protective slope and perhaps some fore/aft optimization). Would be interesting to see how
this comes out with a good measurement system and listening eval. Expect mid/tweet integration to be
the trickiest. Enjoy the journey

[Ian Mackenzie]

Ditto Barry and Grumpy

Disclaimer on support:

Without good driver measurement data (spl amplitude and impedance) from you we can only offer limited general non specific advice where a new member is not closely following a Jbl design.

Unless you have already please invest in a reasonable measurement tool and mic. It will payback with huge time saving and a finished design that you are proud of. You will also learn and appreciate how the whole thing works.

Unfortunately we do see new people come here seeking a customised design consultation over a few posts asking the same naive questions over and over and expecting someone to pull a rabbit out of a hat.

Don’t get hooked on too much internet research. There is no point reading up on a topic and regurgitating it without doing anything.

Yes it happens again and again

The reality is s customised design is one of a kind and the ball is in your court to make it work.

Having said the above good luck with your project.

Quite a few have used the Beyma device and there are numerous projects on diyaudio.com

There are some good Ebooks on loudspeaker measurement.

I recommend you do your own measurements first and establish your own project goals.

The 2123 is nice driver.

An Active crossover with adjustment is a good way to start for the diy person

I would definitely Biamp the woofer and the 2123 or if you can only passive use the Jbl 4344mk11 schematic as a starting point.

[Drummerboy2]

Ditto Barry and Grumpy

Disclaimer on support:

Without good driver measurement data (spl amplitude and impedance) from you we can only offer limited general non specific advice where a new member is not closely following a Jbl design.

Unless you have already please invest in a reasonable measurement tool and mic. It will payback with huge time saving and a finished design that you are proud of. You will also learn and appreciate how the whole thing works.

Unfortunately we do see new people come here seeking a customised design consultation over a few posts asking the same naive questions over and over and expecting someone to pull a rabbit out of a hat.

Don’t get hooked on too much internet research. There is no point reading up on a topic and regurgitating it without doing anything.

Yes it happens again and again

The reality is s customised design is one of a kind and the ball is in your court to make it work.

Having said the above good luck with your project.

Quite a few have used the Beyma device and there are numerous projects on diyaudio.com

There are some good Ebooks on loudspeaker measurement.

I recommend you do your own measurements first and establish your own project goals.

The 2123 is nice driver.

An Active crossover with adjustment is a good way to start for the diy person

I would definitely Biamp the woofer and the 2123 or if you can only passive use the Jbl 4344mk11 schematic as a starting point.

Well, I just wanted some feedback on IF anyone has used these drivers together in any DIY project and NOT free consultation on a custom design. I do have some measuring software and tools. I will just wait for my Beymas to come in and get started on my project. Thanks Everyone for the info and feedback.

[Ian Mackenzie]

Well that’s not what you specifically asked or stated.

Your post was a sprawling story of your options.

Why would you start off with a mix of drivers if you were planning on a 4345? Makes no sense.

This is a JBL forum. That’s it.

[Drummerboy2]

Hello all, here's and update to what I have done. I know it's been a while but I was laid off again and had to wait for awhile to get the funds for these drivers, horns and lenses. Today I was able to buy some JBL 2420's and 2307's in excellent condition, I also bought some Kenrick 2308 lenses to go with my 2245H's and 2123H's. So I'm just missing the JBL 2405's for the supper tweeter. If I can't find any the Beyma version will work but I want the original JBL's.

I will be gathering the parts next for the Xovers for the 3435 II's while I wait for the woofer to be reconed along with any other parts for the cabs.

[Ian Mackenzie]

Just be aware the Beyma slot has lower sensitivity than the 2405H.

Try Jammin Jersey in Northridge CA

[Drummerboy2]

Just be aware the Beyma slot has lower sensitivity than the 2405H.

Try Jammin Jersey in Northridge CA

I went to the website but it looks like its no longer a working website. I will call the number tomorrow that came up in a search.

[Ian Mackenzie]

https://jamminjersey.com/detail/0074...-slot-tweeters

Click on the link and you can email Mark Leonard. I bought a large shipment recently and it was well organised.

[Drummerboy2]

https://jamminjersey.com/detail/0074...-slot-tweeters

Click on the link and you can email Mark Leonard. I bought a large shipment recently and it was well organised.

Ian, Thank You. I placed the order today for the 2405H's. once I receive these, I will have all the JBL drivers to start the build. I also picked up some foilcals for the my project. I just need the pot covers for the pots to look like the originals. I now need to pick up some more wood for the cabs, I already have half of it.

I dropped off the the 2245H's woofers yesterday to Upland Speaker repair to be reconed. So once I get these back I will send the 2123H's in to him to be works on as well (the one I accidently messed up while unpacking it).