I have been working with a specific driver and have tried in many configurations all of which show strengths and weakness as expected. However I have found a very very unexpected result when working with phase:
1. sealed enclosure very clear difference in overall system bass response when phase was reversed. Clearly the bass response was reduced and thin.
2. Ported enclosure: in phase vs out of phase sound difference was not as pronounced. In phase had more output across most of the spectrum and actually got muddier around tuning frequency...less accurate and almost out of phase sounding. Basically not as cut and dry as to which sounded better but still in phase was better......
3. 4th order bandpass. Not a clear winner. in phase, out of phase.....the sound is just "there". Thick, sloppy and kind of undefined in general. No huge difference in phase or out.........
It seems like the further i deviate from sealed the bigger phase issues i am finding...is this group delay> ?
1. sealed enclosure very clear difference in overall system bass response when phase was reversed. Clearly the bass response was reduced and thin.
2. Ported enclosure: in phase vs out of phase sound difference was not as pronounced. In phase had more output across most of the spectrum and actually got muddier around tuning frequency...less accurate and almost out of phase sounding. Basically not as cut and dry as to which sounded better but still in phase was better......
3. 4th order bandpass. Not a clear winner. in phase, out of phase.....the sound is just "there". Thick, sloppy and kind of undefined in general. No huge difference in phase or out.........
It seems like the further i deviate from sealed the bigger phase issues i am finding...is this group delay> ?
If you're hearing that much difference, then it sounds to me like your system is allowing too much overlap over what the subwoofer is trying to reproduce and when the main speakers are trying to reproduce. With proper filtering, you should only notice response changes in a small band around the x-over frequency, not all across the passband of the subwoofer (especially down to its resonance frequency in the case of a vented subwoofer, as that defines the LOWER end of its passband).
Note: 4th order BP boxes need to be filtered a little differently than regular sealed and vented designs, as there is already some acoustic filtering going on. A sharper cutoff at the upper end of the passband is not necessarily better.
Note: 4th order BP boxes need to be filtered a little differently than regular sealed and vented designs, as there is already some acoustic filtering going on. A sharper cutoff at the upper end of the passband is not necessarily better.
My system needs 12,9ms delay (over 10ms more than sealed) over sub if sub is bandpass, might be reason why they usually sound sloppy.
Likely because the bandpass alignment is already (acoustically) filtered. If low-passing them, you're adding a filter in series with the existing acoustic filter. And each filter adds its own delay. It might be possible to minimize this effect by using a LP filter that's way out of the BP subwoofer's passband.
- Status
- Not open for further replies.