Originally Posted by pau
I Have a couple questions before pulling the trigger and trading SB13u to PC4000 for my apartment.
1. The floors are laminated concrete and i have people living downstairs that havent really noticed/bothered with me playing SB13u (playing moderately loud only at casual times not sleeping times) so is the downfiring PC4000 going to sound 'more' to the people living downstairs?
2. Only using boosted (DEQ, +bass trim) moderate volume levels is the upgrade bringing more grunt to movies thats worth the trade? What i mean is, can there be heard/feld difference in 10-20hz range that can be boosted in even lower volume levels in going to ported subwoofer or am i just blowing trades and not archieving anything spectacular without making the neighbours angry? [IMG class=inlineimg]/forum/images/smilies/smile.gif[/IMG]
If you are interested in having more low-frequency bass, that can be both heard and felt, then the upgrade will be worth the trade. The PC4000 will have a lot more <35Hz SPL than the SB13 has, and it will also produce a lot more tactile energy. That's the low-bass you can feel. Those low-frequency sound waves, and the unheard vibrations that accompany them, do travel through adjoining spaces though, so as you add more low-frequency SPL and TR (tactile response) compared to what you have now, you will need to continue to be careful about your neighbors.
Perhaps you could invite them up for a movie sometime and discuss ways that they can let you know, politely, if your movie watching ever starts to really bother them. And, on those occasions, you would just back-off the volume of the sub, or use one of several other measures to reduce the low-bass. It won't be primarily the direction that the driver points, however, which determines whether they can feel or hear something.
Bass sound waves radiate omnidirectionally from the cabinet, and the ports (which point upward on the PC4000) probably contribute even more to the particle velocity (air movement) which helps to create the low-frequency vibrations we feel. Those vibrations are carried through the air, although the concrete floor will also carry some vibrations. (Since you are on a suspended
concrete floor, I would probably try putting something under the sub, such as isolation feet or a SubDude, just in case.) But, the vibrations that you feel won't be primarily from the sub's physical contact with the floor, or from the down-firing driver--the vibrations are carried mainly through the air, the way they are in a thunderstorm. I hope all of that made sense. [IMG class=inlineimg]/forum/images/smilies/tongue.gif[/IMG]
I would do the upgrade, if I were interested in having what you described as more "grunt" to movies. The PC4000 will have a little deeper tone, even after Audyssey EQ's it, and even at moderate volume levels. But, you will always still control the volume and you will always have multiple ways to back-off the low-bass a bit when you want to (different tuning options, RLO settings, Low Frequency Containment, sub volume, etc.). And, on those occasions when you really do want to cut loose, it will deliver much more of what you are looking for than the sealed model will. The PC4000 is also a little better subwoofer with some cool features. [IMG class=inlineimg]/forum/images/smilies/smile.gif[/IMG]