JBL4530 bluetooth box

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   dear readers,
recently i have begun a project to enhance a speaker box that i had used as a workshop speaker for a while now, an old JBL 4530. i have verified that the enclosure was built correctly, according to the document i have found on hornplans.free.fr

from the hornresp database thread i took the values for the 4530, and started simulating drivers that i have or consider within my budget… among those i have simulated i post a screenshot of the b&c 15ndl76

i double clicked on sd and gave it the t&s it wanted

i am a little surprised that it shows almost 15dB gain from the horn, over the 100dB sensitivity b&c reports? but, surely, i would take it

after measuring the setup, my plan is to do some reduction via EQ to shape the response to what i tried to mark green in the response graph. is that a doable approach?

crossover to HF is at 800hz. currently i am using a oberton ndc72-8 on a vintage 6cell cinema horn. 
amping and dsp is wondom jab5, so it is not a maximum spl thing, but a fun bluetooth speaker 

any input is appreceated!

cheers! julius.

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julius111 Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 04 September 2021 Location: cologne Status: Offline Points: 57	Post Options Post Reply Quote julius111 Report Post Thanks(0) Quote Reply Topic: JBL4530 bluetooth box Posted: 04 July 2025 at 8:33am
	dear readers, recently i have begun a project to enhance a speaker box that i had used as a workshop speaker for a while now, an old JBL 4530. i have verified that the enclosure was built correctly, according to the document i have found on hornplans.free.fr from the hornresp database thread i took the values for the 4530, and started simulating drivers that i have or consider within my budget… among those i have simulated i post a screenshot of the b&c 15ndl76 i double clicked on sd and gave it the t&s it wanted i am a little surprised that it shows almost 15dB gain from the horn, over the 100dB sensitivity b&c reports? but, surely, i would take it after measuring the setup, my plan is to do some reduction via EQ to shape the response to what i tried to mark green in the response graph. is that a doable approach? crossover to HF is at 800hz. currently i am using a oberton ndc72-8 on a vintage 6cell cinema horn. amping and dsp is wondom jab5, so it is not a maximum spl thing, but a fun bluetooth speaker any input is appreceated! cheers! julius.

DMorison Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 14 March 2007 Location: Aberdeen Status: Offline Points: 1740	Post Options Post Reply Quote DMorison Report Post Thanks(0) Quote Reply Posted: 04 July 2025 at 12:55pm
	Reset the "ang" input field to 2 x Pi if you want your model to be more directly comparable to B&C's data. That's because the manufacturer's data is measured with the driver on a flat baffle, which we often call "half-space", whereas you're currently modelling in "eighth-space" - the equivalent of putting the speaker in an acoustically perfect corner such that the walls & floor of the room significantly extend the horn. HTH, David.

julius111 Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 04 September 2021 Location: cologne Status: Offline Points: 57	Post Options Post Reply Quote julius111 Report Post Thanks(0) Quote Reply Posted: 07 July 2025 at 10:14am
	thank you for pointing that out, david! now this looks a lot different, and i am probably not going to use that driver currently looking at celestion tf1530 (black) or fane sovereign 15-600lf (grey) the celestion checks on qts (.281) , fs (42) and bl (21.22) for that bin, right? but i am still open to suggestions on the driver best, Julius Edited by julius111 - 07 July 2025 at 10:15am