I just had a thought while looking at this forum. What would happen if you iso loaded two db's, then removed the covers on the vented ends, and butted the two db's together?

'twas just somethin' that popped in my head and I figured I'd toss it up for discussion.

if the 2 dbs would share the sealed chamber, you would end up with something like a tunable hw

dd, don't try to steal my ideas  >:(  :D

imagine 2 db12s put togheter. that would be one tall mother f-er.
gex, having 2 dbs sharing the sealed chamber would be a diffrent animal from your tunable hw. you said that the center chamber was meant to be tunable in you 'experiment'. but having 2 dbs means that you can tune all the three chambers, and play with the freq the vented chambers are tuned at.
it would probalby be more accurate than a hw  ???

agreed about iso. you would free some storage space

The sealed chamber for two woofers wouldn't have to be as large as a single chamber for the same subs.  The iso loading would have the VAS of each driver, allowing you to place them in half the size.

I would imagine with two subs which are isoloaded yet two of them in the same selaed chamber would work best with the sealed chamber the same size.

yes this has been talked abotu before also, i still got the pics I drew to explain better.

well, in that case, i would tune a normal DB to what sound sbest, then half that volume for the volume at the ends of the box in your drawing.

The middel would then be twice the distance from the top by the port, with the port being two half moons pushed together.

It would look seriously tight though, and would have th epotential to kick ass.

Maybe a little more simple, and smaller version.


I'm guessing that other baffle design is the DBII and this is the original DB. Ive just been researching pictures on the forum.

id say build 2 seperate dbs exactly like plans and run em like that, mixing / blending output like you have in the drawing might not be a good thing? good in a wo, maybe maybe not good in the db? i have run 2 x dbs in a trunk. sweet.

Would you not have a phase issue(iso-loaded DBs) with running speakers in phase in different chambers? I have tried two DBs(iso-loaded) with the sealed chamber connected to each other. I took the baffle(cut out attached to the lid) and used it to couple the DBs together. It sounded pretty good but phasing seem to be a problem,I think ???. I did not have enough time to finish the test before someone want to hear them separately. The reason I think phasing is an issue is that the DBs hooked together were easier to overdrive with less power than if you were running them separate. With the DBs hooked together also caused excessive heat from the amp. The only data I have to go by is comparing them run separate and then bolting them together, so more test need to be run. If anyone has any luck with this combo I would like to know as much info as possible and the different ways you could test this set up. Thanks.  HT-EXT

Well, you could esily throw the ends into phase with eachother.  That way the output from the port is in phase from both of the subs on the ends.  With that much air being able to move in and out, the subs could easily push against each other and not experience any problems, where running them in the same sealed chamber out of phase would make it a very difficult task for the Drivers.

I other words:

thats a toughy there.

Normal Ported boxes have a considerable delay, however, the Db is just a normal box, since it is tuneable.

I would say you would have to measure the delay with a computer or other device.

In short, yes there is a delay. I wouldn't expect it to be more than the WO though.