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I finally managed to build my first self-made (and designed) speaker, a Tapped Horn tuned to 25 Hz. After running hundreds of calculations with HornResp, with different drivers and horn parameters, a compact size (for a horn) in mind, I ended in TB Speakers W8-740P, which is an 8" long-excursion woofer with paper cone.
It's made of 18mm birch glulam, grade AB to at least save some € if turns out to be a failure. I had never heard or even seen such thing, but DIY people who had made these kind of subs talked about them in very good light so I gave it a try. Luckily, HornResp also turned out to be quite correct.
The whole process took less than a month: calculating with HornResp during a couple of weeks, a week of CAD drawing, and 3 days of building.
Without cover, all electronics inside. 2.7 mH low-resistance coil was added to dip peaks @ around 70 Hz.
Lying on the floor, Nokia cell phone charger on top to give a scale. **** load of screws, I now think I could have sealed it with almost half.
Dimensions in cm:
W: 131
H: 26
D: 52
A look in the mouth during out-door testing, the part of the carpet which wasn't under it started levitating @ below 30 Hz when I cranked up a bit...
Standing in my friend's apartment where we tested it with HT receiver/amplifier. He was quite astonished, said he had never heard such a good bass in his system, even when he had 2 single-15" loaded subs at the same time (sealed or reflex, I don't remember).
That exact place seemed to be the best we could put it - the whole room front of sub seemed to be "a sweet spot". We walked around the room and it was the same all the time, and when we leaned to wall it still was the same, not a single honk or boom in the whole room, even close to walls. Neither of us had ever experienced such a thing. I think THAT room is special...
However, I didn't quite end in a result I had in mind. I made sine wave tests and it isn't as flat as supposed down to 25 Hz. Output level starts to fade a bit below 35 Hz. After doing some research, I found out that the compact size might have took it's toll - the mouth is just too small to keep flat tone-wise at such low frequencies. The pressure is there, I think the levitating carpet pretty much proves that, just less tone. I also felt pressure in my ears the rest of the both days I made sine wave tests.
This probably isn't the last Tapped Horn I make, I still have 1 8" TB driver in my closet, and found a new one, 6,5" which seems to be very promising... Will probably make a dual 8"/6,5" push-pull with throat chamber in close future.
It's made of 18mm birch glulam, grade AB to at least save some € if turns out to be a failure. I had never heard or even seen such thing, but DIY people who had made these kind of subs talked about them in very good light so I gave it a try. Luckily, HornResp also turned out to be quite correct.
The whole process took less than a month: calculating with HornResp during a couple of weeks, a week of CAD drawing, and 3 days of building.
Without cover, all electronics inside. 2.7 mH low-resistance coil was added to dip peaks @ around 70 Hz.
Lying on the floor, Nokia cell phone charger on top to give a scale. **** load of screws, I now think I could have sealed it with almost half.
Dimensions in cm:
W: 131
H: 26
D: 52
A look in the mouth during out-door testing, the part of the carpet which wasn't under it started levitating @ below 30 Hz when I cranked up a bit...
Standing in my friend's apartment where we tested it with HT receiver/amplifier. He was quite astonished, said he had never heard such a good bass in his system, even when he had 2 single-15" loaded subs at the same time (sealed or reflex, I don't remember).
That exact place seemed to be the best we could put it - the whole room front of sub seemed to be "a sweet spot". We walked around the room and it was the same all the time, and when we leaned to wall it still was the same, not a single honk or boom in the whole room, even close to walls. Neither of us had ever experienced such a thing. I think THAT room is special...
However, I didn't quite end in a result I had in mind. I made sine wave tests and it isn't as flat as supposed down to 25 Hz. Output level starts to fade a bit below 35 Hz. After doing some research, I found out that the compact size might have took it's toll - the mouth is just too small to keep flat tone-wise at such low frequencies. The pressure is there, I think the levitating carpet pretty much proves that, just less tone. I also felt pressure in my ears the rest of the both days I made sine wave tests.
This probably isn't the last Tapped Horn I make, I still have 1 8" TB driver in my closet, and found a new one, 6,5" which seems to be very promising... Will probably make a dual 8"/6,5" push-pull with throat chamber in close future.