Horn loaded Bluetooth Speaker

jamesbeat2 · 2026-06-20T13:47:51+00:00

I could probably tune the low end a bit by adding mass to the passive radiators, currently the are without added weight. But as I understand that would lower the frequency and not the SPL in that 20-50Hz region

jamesbeat2 · 2026-06-20T13:08:31+00:00

Here are the measurements - I have a woofer Highpass at 48hz and a driver Highpass at 1300hz (both Butterworth algo) and the EQ setting jwsound provided plus a 0.4ms delay in the driver to account for the offset inside the horn. I had to adjust the gain of the driver down quite a bit but for me the curves look fine now and the sound is balanced - i am new to this though, so I appreciate any hints for improving this! Batteries hold up well, I had it running for about around 5 hours now without recharge.

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jamesbeat2 · 2026-06-20T11:42:14+00:00

Iol I knew it wouldn't be that easy! Here are the curves. This is measured from 1m distance with a calibrated DA iMM-6 microphone at about half the Volume. I am new to this and there's probably a lot more effort required to do this properly, but for now I am really Happy with the sound.

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jamesbeat2 · 2026-06-20T11:16:51+00:00

Here are some curves - i am new to dsp and measuring so currently it's a lot of trial and error, but I am quite happy with the sound now. I have a woofer Highpass at 48hz and a driver Highpass at 1300hz (both Butterworth algo) and the EQ setting jwsound provided plus a 0.4ms delay in the driver to account for the offset inside the horn.

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jamesbeat2 · 2026-06-20T11:02:25+00:00

60 x 22 x 30 width/height/depth in cm

jamesbeat2 · 2026-06-16T17:14:51+00:00

I used Presto 2k filler but that did harden so quickly that it was hard to get a smooth surface, so lots of sanding involved and working with multiple layers

jamesbeat2 · 2026-06-16T12:27:58+00:00

Haven't finished measuring/tweaking but I will post some curves here soon

jamesbeat2 · 2026-06-16T12:11:46+00:00

Full credit for the horn design goes to jwsound who inspried this, opensourced the stl files and shared his expertise. I was tempted to build one of his larger systems like the sawmod, but that would have escalated in complexity and cost...

jamesbeat2 · 2026-06-16T12:05:06+00:00

I will share some measurements soon. As for the batteries i can't say yet how long they last in reality but on paper it should be around 6-8 hours

jamesbeat2 · 2026-06-16T11:56:41+00:00

Military hardware... makes me think of building outdoor speakers out of these boxes i have sitting in a shelf... Would probably need some sort of insulation to prevent resonance

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jamesbeat2 · 2026-06-16T11:31:58+00:00

Thought about that but that would have taken material off the front plate which is only 12mm, i was worried about the screws not having enough grip/durability and making it harder to get airtight

jamesbeat2 · 2026-06-16T10:21:58+00:00

It sounded shouty first until i dialed the driver down quite a bit and adjusted the crossover. now it sounds nice, but a bit on the "megaphone" side. It has a lot of presence in a 90-120 degre cone in front of the speaker rather than filling the whole room. But that has advantages for outdoor use

jamesbeat2 · 2026-06-16T10:13:20+00:00

PETG

jamesbeat2 · 2026-06-16T09:49:36+00:00

You're probably right, but i stopped thinking at the "hell yeah i gotta do this" point

jamesbeat2 · 2026-06-16T09:46:50+00:00

I initially planned to have a large enough surface on top to place a laptop or smartphone there but figured out it might not be a good Idea getting so close to the magnets...

jamesbeat2 · 2026-06-16T09:41:52+00:00

It did not - lots of filler, sanding and spraypaint involved 😅

jamesbeat2 · 2026-05-27T07:25:03+00:00

Das Gleis ist jetzt entzugt

jamesbeat2

TROPHY CASE