Some time ago I bought a JBL Stage 1010 and an enclosure because they were cheap and practical. The box is sealed and quite small, only 17 litres, where the manufacturer recommends a volume of 35 litres when using a sealed enclosure. The 225W RMS rated woofer is driven by a 120W RMS rated amp with the gain almost turned to the maximum.
The problem is that the sound pressure at lower frequencies (I think below 80-90 Hz) is very low. I think the small enclosure makes the woofer roll off really early.
Now I'm thinking about building a new enclosure. I prefer a ported box for practical and efficiency reasons. The manual recommends a volume of 28,5L when using a vented box. I find it very strange that the recommended volume for the closed box is greater than that of the closed box. I used WinISD and it recommend me a 22L for a closed box which makes more sense to me. However, I don't really know what I'm doing. Maybe this sub just likes closed boxes.
Can someone help me decide on a box? Or point me in the right direction? I don't really trust the manufacturers recommandations. The TS parameters can be found in the manual I linked.
Thanks in advance.
The problem is that the sound pressure at lower frequencies (I think below 80-90 Hz) is very low. I think the small enclosure makes the woofer roll off really early.
Now I'm thinking about building a new enclosure. I prefer a ported box for practical and efficiency reasons. The manual recommends a volume of 28,5L when using a vented box. I find it very strange that the recommended volume for the closed box is greater than that of the closed box. I used WinISD and it recommend me a 22L for a closed box which makes more sense to me. However, I don't really know what I'm doing. Maybe this sub just likes closed boxes.
Can someone help me decide on a box? Or point me in the right direction? I don't really trust the manufacturers recommandations. The TS parameters can be found in the manual I linked.
Thanks in advance.
I come with the data supplied to a 25L sealed box for an F6 of 50Hz and a qtc of 0.707. And 17L won't change that much. I suspect that the box is leaky and so tuned to high.
A 50L vented will you easely bring the F3 in the low 30Hz, 28.5L will give it a very uneven response and tuning so not an option. The smallest i would go is 40L (for a 35Hz tuning), but 50L/35Hz tuning is better i think.
A 50L vented will you easely bring the F3 in the low 30Hz, 28.5L will give it a very uneven response and tuning so not an option. The smallest i would go is 40L (for a 35Hz tuning), but 50L/35Hz tuning is better i think.
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Thanks for the quick response. I was also thinking something along those lines. I thought I was doing something wrong but I get similar figures. How did JBL come to their recommendations? It is really confusing me. Isn't a sealed box supposed to be significantly smaller than a vented box?
That driver has a fairly low Xmax, so that may explain why JBL suggested a smaller box and higher tuning (50 Hz is pretty high for a car audio 10" driver these days).
Interestingly enough, the specs of that driver suggest that it might be a good match for my "Enigma" 4th order BP build...
Interestingly enough, the specs of that driver suggest that it might be a good match for my "Enigma" 4th order BP build...
Manufacturers recommend vented cab alignments that will protect them as much as practical from folks over driving them to destruction. Sealed is somewhat self protected, so size is chosen for best overall blend with room/cabin gain.
For mobile audio and corner loaded HIFI/HT apps, the pioneer's vented alignment of ~Vas/1.44 = 28.5 L is a good one except tuned to the pioneer's Fb = Fs as a compromise for more bass, smoother response.
GM
For mobile audio and corner loaded HIFI/HT apps, the pioneer's vented alignment of ~Vas/1.44 = 28.5 L is a good one except tuned to the pioneer's Fb = Fs as a compromise for more bass, smoother response.
GM