Erin Hardison made a video in 2023 of a ported tweeter. He said it was made by someone named "Alex" who was going to file a patent.
I haven't seen anything more on that since then, so I thought I'd take a crack at reverse engineering it.
This is the ported tweeter that Erin reviewed.
Pic is from his FB.
Go subscribe to his channel and buy your merch using his link:
Here's Alex's website: www.referenceacoustics.com
Here's a graph from Alex's website, illustrating the difference in SPL.
Here's a graph from Alex's website, illustrating the difference in excursion.
This is a ScanSpeak D3004/6600. For sale at Madisound for $228: https://www.madisoundspeakerstore.c...inator-d3004/6600-aircirc-tweeter-textile-dom
In order to make a Ported Tweeter, I believe Alex simply drilled holes through the faceplate, to allow the radiation from the rear of the diaphragm to "vent" through the faceplate.
Scan Speak hasn't published full Thiele Small for this tweeter: https://www.madisound.com/pdf/scanspeak/D3004_660000.pdf
But I think that's kinda irrelevant. I have an idea of how you could port it:
Basically, you buy a set of drill bits, and then you drill progressively larger ports, until you get the frequency response you're looking for. As with any ported box, you can trade efficiency for bandwidth.
If you don't want to spend $230 on a tweeter, this "trick" should work with any tweeter that you can expose the back side. IE, if the magnet is solid, it won't work. But most of the 1" and 1.125" SB Acoustics Tweeters, they'll work. I used the SB29ADC in my experiments with metamaterial absorbers:
I haven't seen anything more on that since then, so I thought I'd take a crack at reverse engineering it.
This is the ported tweeter that Erin reviewed.
Pic is from his FB.
Go subscribe to his channel and buy your merch using his link:
Here's Alex's website: www.referenceacoustics.com
Here's a graph from Alex's website, illustrating the difference in SPL.
Here's a graph from Alex's website, illustrating the difference in excursion.
This is a ScanSpeak D3004/6600. For sale at Madisound for $228: https://www.madisoundspeakerstore.c...inator-d3004/6600-aircirc-tweeter-textile-dom
In order to make a Ported Tweeter, I believe Alex simply drilled holes through the faceplate, to allow the radiation from the rear of the diaphragm to "vent" through the faceplate.
Scan Speak hasn't published full Thiele Small for this tweeter: https://www.madisound.com/pdf/scanspeak/D3004_660000.pdf
But I think that's kinda irrelevant. I have an idea of how you could port it:
Basically, you buy a set of drill bits, and then you drill progressively larger ports, until you get the frequency response you're looking for. As with any ported box, you can trade efficiency for bandwidth.
If you don't want to spend $230 on a tweeter, this "trick" should work with any tweeter that you can expose the back side. IE, if the magnet is solid, it won't work. But most of the 1" and 1.125" SB Acoustics Tweeters, they'll work. I used the SB29ADC in my experiments with metamaterial absorbers:
Here's a Unity horn I threw together over the weekend.
It uses two MCM 55-1870 woofers and an SB 26 ADC tweeter with a metamaterial back chamber.
Here's the waveguide. It's loosely based on QSC's waveguide.
It uses two MCM 55-1870 woofers and an SB 26 ADC tweeter with a metamaterial back chamber.
Here's the waveguide. It's loosely based on QSC's waveguide.
I thought the same thing.
Here's the conversation between Andrew Jones (ELAC) and I:
Based on the sims that I've run in Hornresp, nulling that back wave seems to be pretty important. I've been building speakers for decades, and I'd always been dismissive of guys like Richard Vandersteen, who are kinda obsessive about eliminating reflections off of the driver basket.
But there may be something to this; in particular the hornresp sims seem to indicate that the reflected wave off of the back of the speaker chamber impacts what's radiated by the FRONT...
Here's the conversation between Andrew Jones (ELAC) and I:
Based on the sims that I've run in Hornresp, nulling that back wave seems to be pretty important. I've been building speakers for decades, and I'd always been dismissive of guys like Richard Vandersteen, who are kinda obsessive about eliminating reflections off of the driver basket.
But there may be something to this; in particular the hornresp sims seem to indicate that the reflected wave off of the back of the speaker chamber impacts what's radiated by the FRONT...