As mentioned - the tuning slot can be trimmed in shape. To some extent it is just a restrictor - like a reduction ring in a flow system.
Talking about big SLOB's Some might have seen this article : https://www.labjc.com/?p=4230
Talking about big SLOB's Some might have seen this article : https://www.labjc.com/?p=4230
I don't know. The distortion is not off the charts bad. But multiples of the ESS, especially more odd order which is super low on the Heil. And sonically I feel they always lack the realism and effortlessness of the AMT. Still better than the few domes I tried though.
I found the old 15" Ripole in storage! I thought I I tossed them while moving house but apparently I didn't.
At the time I didn't have DSP and now I discovered that with a properly steep crossover they sound halfway decent, way better than I remember. They sound good on most acoustic music but with edm they fall apart. I think that is cone breakup from the super cheap 15" paper cones. I remember lots of flopping and buzzing when I tested there drivers naked.
With smaller better constructed drivers I think won't have those problems.
I found some really cheap locally produced 12" drivers that have a stellar reputation, vented spider and high BL vs MMS. The frames are stamped steel but extremely heavy duty. The qts is quite low and fs highish.
What kind of response should I expect from this driver in Ripole? Xmax is only 4.1mm but I plan to use 4 pairs per speaker. I am hoping mid to low 30's
Sensitivity (1W/1m) 96 dB
FS Hz 48 Hz
Vas 92.5 lt
Qms 9.0
Qes 0.36
Qts 0.34
BL T/m 14.7 T/m
MMS (gms) 47.8 grams
Xmax (mm) 4.1 mm
Efficiency% 2.75%
I was wrong about it having a vented spider. But since it isn't exactly long throw that may not really matter that much.
The most important thing with a Ripole design is the crossover. It has to eliminate the peak that comes from the principle.
If you ignore the design rules of the Ripole, you end up with something very different. You can not ignore the front and back chamber and expect it to work as supposed. Volumes are important too.
In the end, when you got the hardware (including crossover!) right, it is all about placement in the room. It is in no way as tollerant as a closed or vented construction.
PS I would not use such drivers as the 12" you showed. If you insist, maybe buy one and measure TSP. Usually these dont match.
If you ignore the design rules of the Ripole, you end up with something very different. You can not ignore the front and back chamber and expect it to work as supposed. Volumes are important too.
In the end, when you got the hardware (including crossover!) right, it is all about placement in the room. It is in no way as tollerant as a closed or vented construction.
PS I would not use such drivers as the 12" you showed. If you insist, maybe buy one and measure TSP. Usually these dont match.
Thanks, great article. It kind of validates my gut feeling to go for higher SD and lower xmax.
Pefpef is right. It takes a lot of air displacement when you shift Fs to half, 4x
It also makes it easy to get close to Xlim on low level content @ otherwise well known playback levels.
I had a scary moment with a Terje Isungset track, where they recorded Glaciers, giving birth to new icebergs. The true extent of that track had escaped me until then ;-)
Yes, but from 18" upwards the problems escalate mechanically, and it is not just convenience, that is keeping almost all the producers, from going bigger. It becomes very difficult, to control the break-up modes, on the membrane and ensure that is is still somewhat acting as a piston, without excessive weight to retain stiffness.
But it might work - all depends on the levels you wan't to play back at and how absorbing your room is.
I'd look for lower Fs (<35), around same Q and higher Xmax, (but that is really a displacement calculation Sd x Xp-p)