Hello.
I'm thinking of making a two-way with SB17nbac35-4.
Would like help with the volume on the box. Don't know what type of box is suitable. Bass reflex or something else.
Feel free to make suggestions.
I'm thinking of making a two-way with SB17nbac35-4.
Would like help with the volume on the box. Don't know what type of box is suitable. Bass reflex or something else.
Feel free to make suggestions.
I use the SB17CAC-8 (different cone material, same motor) in a 16L sealed box. I used a 4th order filter on the driver (L: 1.2mH C: 10uF , L: 0.6mH C: 10uF) to supress of the nasty spike above 2kHz.
Bass is quite good. I use it in a small room and close to the back wall, so very little baffle step corrections are needed in my setup.
Bass is quite good. I use it in a small room and close to the back wall, so very little baffle step corrections are needed in my setup.
I also made a small 2-way using the SB17NBAC35-4, in a sealed 12.4 liter cabinet. It is a good driver.
tall thin work shop speaker
This speaker was for my brother's workshop, and he needed it narrow and tall. The woofer and tweeter are spaced widely so that the directivity is well managed through the crossover region. It looks odd, but it sounds great. The Bromo kit is also a good choice of course.
j.
tall thin work shop speaker
This speaker was for my brother's workshop, and he needed it narrow and tall. The woofer and tweeter are spaced widely so that the directivity is well managed through the crossover region. It looks odd, but it sounds great. The Bromo kit is also a good choice of course.
j.
I think I did 16-17L for 17NBAC 4 ohm version but Qts was way higher than listed in specs, around 0.45. Tuned close to drivers free air Fs, mid, upper 30tish Hz. Crossover is tricky on this one, mine around 2k 4rd order LR with RLC trap to resonance around 9k. And yeah it has this brightness to it. Detailed and low dist in the mids but not that easy to work with. If i had better tweeter at the time I would cut it around 1.5k.
Unlike jayme's close to the wall design I went for more into the room baffle compensation. I would like to try the composite cone version one day, supposedly sounds the best of them all.
Unlike jayme's close to the wall design I went for more into the room baffle compensation. I would like to try the composite cone version one day, supposedly sounds the best of them all.
That sounds like a really intriguing setup. Can I ask a few questions: how did the higher Qts influence the overall sound? And was the RLC trap needed to control the resonance at 9kHz?
Higher Qts just adds more bass - it's most likely due to measuring condition set up by CLIO, which sends 0.775V or 1V to the driver. You can simulate the change in Vituix or similar CAD: increase in the Qes(Qts) by adding more resistance in series with the driver, same as high resistance coil in crossover. Seems like everyone measures higher Qes/Qts than in SB specs, HiFi Compass, AudioExcite, Erin. It dropped in my samples by 10% after some use. You could add additional magnet to the back to lower the Qes and boost the efficiency slightly.
The series RLC trap network in parallel with the woofer is not that really necessary - just 0.2mH 20ga coil, 2.4uF and 2.4ohm resistor (similar combination will do trick), parts are cheap so why not, transfer function is better past the 4-5kHz and the subharmonics due to cone breakup are lower. Similar result can obtained with capacitor - there was a reason why I went RLC. The tweeter came from a friend of mine Mark Kravchenko who got series of the modified by him CSS LD25 tweeters made by very reputable manufacturer in Guangdong some 15yrs ago. We put them into short waveguide, fabicated from/into front baffle. We also put oval 5x8 passive radiator on the back, but it didn't make a huge difference comparing to rear mounted 2" port. Maybe one day I will go back and redo/retune the x-o again, or use one of Marks planar tweeters with it. There is definitive peak around 3k and then higher up in 17NAC(CAC), which most likely add some brightness, but then all Alu cones have this bright character, especially compared to softer paper cones.
The series RLC trap network in parallel with the woofer is not that really necessary - just 0.2mH 20ga coil, 2.4uF and 2.4ohm resistor (similar combination will do trick), parts are cheap so why not, transfer function is better past the 4-5kHz and the subharmonics due to cone breakup are lower. Similar result can obtained with capacitor - there was a reason why I went RLC. The tweeter came from a friend of mine Mark Kravchenko who got series of the modified by him CSS LD25 tweeters made by very reputable manufacturer in Guangdong some 15yrs ago. We put them into short waveguide, fabicated from/into front baffle. We also put oval 5x8 passive radiator on the back, but it didn't make a huge difference comparing to rear mounted 2" port. Maybe one day I will go back and redo/retune the x-o again, or use one of Marks planar tweeters with it. There is definitive peak around 3k and then higher up in 17NAC(CAC), which most likely add some brightness, but then all Alu cones have this bright character, especially compared to softer paper cones.