View Full Version : Sorens 4345 project

04-21-2012, 03:52 AM
Hi everyone, I have used the last year or so browsing this forum and asking small questions about the 4345 speaker, because i would like to build a pair.
I am from denmark and I have listened to a pair of 4333 speakers numerous times, and I realized I wanted a pair of big 43 monitors, and my love for the 4345 started.
I have been gathering the drivers and units for the project over the last year, and I have gathered the following for now:
2X 2245H
2X 2122H
2X 2420
2X 2307 + 2308

the only thing i need is the UHF drivers and i have a pair waiting for me, the only reason i am not rushing is because of the availability of these drivers and my priority with the project.
As I asked in another thread, i was a bit worried with a 2245H purchase i made of ebay, since the cones were a lot different from each other, but with the help of a good friend at JBL i have now ordered two C8R2245 kits directly from JBL, and these kits are my first priority right now.
Once I am done with the collecting of drivers I will start work on the crossovers, I am a bit of a "JBL-Original-Design" guy, and i want the final speaker to perform as the original 4345 not better not worse, so my thought are the biased network diagrams available on this forum but without the double caps and non-biased:p (thus being free of the center tapped transformer) - Then i can experiment with the biased networks after I finished the whole speaker.
After the crossovers I will start work on the cabinets, and I have made arrangements of veneering at a veneering-central with a large veneer press (they will counter-veneer in whole sided american walnut veneer, on MDF), then afterwards I will transport the veneered sides to a professional woodworking craftsman who will make the lock-mitre joints, the routing and assembly of the speaker, per my instructions.
lastly when this is all done, and the custom foilcals from Sign-Shop is ordered, i will assemble and listen - hopefully in a years time from now.:yes:

the only thing i am confused about in this project, and unable to source, is the blue cloth for the grilles, but that must wait for now.

I will keep you updated as i go along!

04-21-2012, 07:58 AM
for original blue cloth email Kenji http://jbl43.com/?mode=f3 he has the Lens also .

Look forward to the build thread .


04-26-2012, 02:21 PM
Thank you for your response regarding the blue cloth - i will contact Kenji when I come around the grilles.
For now i have just ordered 2 C8R2245H kits and 2 C8R2122H kits from my JBL guy. Today i wanted to make sure my 2420's had 16 ohms diaprahms in them, when i measure across the driver with an ohmmeter they measure 5,8 ohms - would that make it a 8 ohm or 16 ohm nominal impedance diapraghm?
If it is an 8 ohm diaphragm, would the 2425J diapraghms be a fit or should i get the expensive 2421 diapraghms?

I appreciate all inputs on the matter ;)

best regards

04-26-2012, 02:28 PM
That would make it 8 ohm .... I had 2425h in mine originally , then TAD 2002 . I would be tempted to go with the Aluminium , or aquaplas the Ti for your project !

You should PM Guido for more info ...


04-26-2012, 02:32 PM
would the D16R2425 be a working fit or is it a no-go? - since I now have to buy new diapraghms, it is important for me to get the right ones, but the price difference is kinda huge....

04-26-2012, 03:29 PM
The original 2121b is 16 ohm ...2425j is 16ohm .... my networks were designed and built by Guido ... I would strongly recommend you pm him or 4313b for advice on this topic ..