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Discussion Starter #1
So i bought a PB-2000 off amazon(didnt realize i dont get the upgrade period) its impressive but i have a null in room(14 x 15 with 8.5ft ceilings) looking to add a second sub to smooth things out. dont really know i need more deep bass output i would like more slam. thought of adding a PB3000, but really the second space i have is pretty small, a PB1000 would fit much better without making things look horrible. So can i mix and match a bit? would having a pb1000 gain me anything or be a waste?
 

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Discussion Starter #3
the couch is slightly favored towards where the PB1000 would be. the PB2000 is front left corner planning to put the other sub in the back right corner. couch is maybe 3 feet behind the center line of the room. The other option i see today is SVS has a deal going on on the older PB12-NSD would it pair nicely with the pb2000? bit worried about size i really need something smaller.
 

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While you can mix, even the folks at SVS would recommend pairing identical. Before you buy anything, why not try some alternative placements with the sub you have? Keep in mind the driver does not have to face you, so you have rotational options at any given floor location. Sometimes a sub that looks big at first doesn’t seem so big after awhile once you’re used to it in a spot.
 

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So i bought a PB-2000 off amazon(didnt realize i dont get the upgrade period) its impressive but i have a null in room(14 x 15 with 8.5ft ceilings) looking to add a second sub to smooth things out. dont really know i need more deep bass output i would like more slam. thought of adding a PB3000, but really the second space i have is pretty small, a PB1000 would fit much better without making things look horrible. So can i mix and match a bit? would having a pb1000 gain me anything or be a waste?
The PC2000 takes only takes up about 17" inches of floor space and would be a great match for the PB version.
 

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the couch is slightly favored towards where the PB1000 would be. the PB2000 is front left corner planning to put the other sub in the back right corner. couch is maybe 3 feet behind the center line of the room. The other option i see today is SVS has a deal going on on the older PB12-NSD would it pair nicely with the pb2000? bit worried about size i really need something smaller.

Hi Ben,

I agree with the advice to pair identical subs, if possible. The PC2000 (the cylinder form) would qualify as identical from a port tune and overall frequency response standpoint. The other subs you mentioned wouldn't. Some of the SVS associates used to be a little ambiguous in their advice about pairing subs which were just one model up or down from an existing sub. Ed Mullen, the chief engineer of SVS, is pretty direct now in the advice he gives. The problem isn't just one of output, which can be alleviated somewhat by nearfield placement. It's a matter of whether you will get cancellation, especially at or below the tuning point on the weaker sub, with two different models with different frequency responses.

That can be hard to predict, but I have definitely seen examples of cancellation between a PB1000 and a PB2000, and between a PB12-NSD and a PB2000. In fact, there are some recent posts on the SVS thread about an owner experiencing cancellation, at 25Hz, from having a PB12-NSD and a PB2000. That cancellation was definitely traced to the difference in frequency response. Since you are already dealing with a null, and are looking to smooth-out the frequency response, identical subs with identical frequency responses will give you a much better opportunity to do that.

Sometimes the cancellation caused by mismatched subs is audible and sometimes it's not. (Mixing subwoofers where the tuning points are very different may actually work better sometimes than where they are only a few Hz apart.) In that recent case I cited, the owner was using REW, and the dip at 25Hz was driving him crazy. Using REW can do that to you! :p

If I were you, I would play it safe with another ported 2000. If you can't make a PB2000 fit in a good second location, then go with a PC2000. Those subs will work perfectly together, and eliminate a potential source of trouble for you. They will also give you better 6db coupling, across the subs' passband, than mismatched subs will.

Aside from potential cancellation, mismatched subs will never give you as much overall SPL, across the full passband, as having two of the stronger model subs would. That will be especially true for the frequencies below about 25 or 30Hz, but it can also affect the mid-bass frequencies, too. The PB2000 is stronger everywhere. Also, although you said that you don't care about the lower frequencies as much right now, you never know. Low-bass tends to grow on us over time. That's a pretty consistent trend for subwoofer owners. :)

Regards,
Mike
 

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the couch is slightly favored towards where the PB1000 would be. the PB2000 is front left corner planning to put the other sub in the back right corner. couch is maybe 3 feet behind the center line of the room. The other option i see today is SVS has a deal going on on the older PB12-NSD would it pair nicely with the pb2000? bit worried about size i really need something smaller.
Pb-12 would be a much better match.
 

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Discussion Starter #8
well the issue is again size i might be able to grease up a pb-12 or pb-2000 and get it in that spot, but i also have a chance to get a good deal on a pair of PB-1000s locally. Thinking about moving the couch back. im only running 5.1.4 right now anyway(been debating on getting an amp and going 7.2.4 but the rooms only 14x 17 not sure really worth it???) place the two pb-1000s right behind the couch? my receiver does do dual sub outs and i think eqs them seperate. its a yamaha 3080.
 

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well the issue is again size i might be able to grease up a pb-12 or pb-2000 and get it in that spot, but i also have a chance to get a good deal on a pair of PB-1000s locally. Thinking about moving the couch back. im only running 5.1.4 right now anyway(been debating on getting an amp and going 7.2.4 but the rooms only 14x 17 not sure really worth it???) place the two pb-1000s right behind the couch? my receiver does do dual sub outs and i think eqs them seperate. its a yamaha 3080.
Not sure if you're talking about the 1000's instead of or in addition to the 2000, but regardless, if the deal's good enough that you could resell later at no loss if things don't work out, you've got nothing to lose by trying. At a minimum, experimenting with duals in different locations will be a learning experience.
 

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Discussion Starter #10
Im talking about leaving my PB2000 where it is then adding 2 PB-1000s directly behind my couch(MLP).
 

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So i bought a PB-2000 off amazon(didnt realize i dont get the upgrade period) its impressive but i have a null in room(14 x 15 with 8.5ft ceilings) looking to add a second sub to smooth things out. dont really know i need more deep bass output i would like more slam. thought of adding a PB3000, but really the second space i have is pretty small, a PB1000 would fit much better without making things look horrible. So can i mix and match a bit? would having a pb1000 gain me anything or be a waste?
There's no reason to pair identical subs. You can get fantastic results with different subs. The additional subs are used for the exact purpose you describe - to fill in the nulls created by room modes. For example, if you have a null at 60Hz, you just need a sub that can give you sufficient output at 60Hz, it doesn't need to be a monster that goes down to 15Hz.


It's described here:

Multiple Subwoofers After Geddes


For placement, there's no way to know where they should go without measuring. If you don't have a measurement mic, pick one up and get Room Eq Wizard. Then follow Geddes' methodology and place your biggest sub in the spot that gives you the most even response in the listening area. Then place your second subwoofer in the spot that fills in the most nulls. Then place the third in the spot that fills in any remaining nulls. Then run Audyssey, Antimode or another EQ solution (if you have time and dedication, you can do it manually with Multi-Sub Optimizer)
 

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Discussion Starter #12
the room has a 4 foot open doorway out into the rest of the house sadly. im not hurting for output, im just really missing some SLAM the chest hit id expect. That i know comes in the 40 to 60hz range not down deep. i feel theres some missing there. I guess im just wandering will i feel the difference enough to justify 700 bucks or so for another sub or the pair of PB1000s. i realize a pb2000 and 2 pb1000s in that space is overkill lol.
 

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If you're most concerned about "chest slam", here's something to try for free.


The phase relationship between your main speakers and subs can affect the bass near the crossover point, which if it's around 80Hz can also be the "punch" for kick drums and the like. Here's how you can see what is happening.


Download or find a test tone at your crossover frequency (say, 80Hz). Find the distance setting for your subwoofer. If you have a measurement mic or SPL meter, use it. If not, download an SPL app for your phone.



Play the 80Hz tone at about 70dB SPL (the exact level isn't important; just a good comfortable level that registers on your meter). Now, start adjusting your subwoofer distance up, and see what happens to the level of the tone. It should rise up and down.


Basically, an 80Hz sound wave is 14.07 feet. If your original sub distance was 10 feet, then as you move from 10 feet to 24 feet, you are effectively moving the subwoofer an entire wavelength away. As you do this, the wave will interact with the tone coming from the main speakers, cancelling at some point and dropping the level.


Adjust the sub distance to a point where you're getting the maximum SPL reading. Let's say that's 16 feet (for example). Now, you need to make sure the sub is in sync with the mains. Find some good music that you are really familiar with that has some kick drums. Play the music, and listen carefully to the kick and other bass parts. Then adjust the subwoofer distance up 14 feet (to 30 feet), and listen again. Is the kick drum tighter or looser? Then go to 44 feet (another wavelength up). Listen again. Hopefully you can hear a difference. Set it at the setting that sounds the most "in sync."


If you can't hear a difference or liked how it was originally, then just set the sub distance back to where you started and no harm done. Otherwise, you may find a better transition between your mains and subs and better "chest punch."


If you get a measurement mic, there's a way to do whit with Room EQ Wizard which is a little more precise. But this will get you started.
 

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As others have stated, in order of preference the 2nd subwoofer choices are PB-2000, PC-2000 (very close FR and phase response), PB12-NSD and PB-1000.

With the help of REW steering placement and phasing, we can help you make any of these subwoofers work - but obviously another identical model will have the same exact phase response and eliminate that variable from the equation.

Integrating dual subs is hard enough (even with REW) - and we try to avoid adding another layer of complexity with potential phase cancellation which otherwise wouldn't occur with the same brand/model as the 2nd subwoofer.
 
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As others have stated, in order of preference the 2nd subwoofer choices are PB-2000, PC-2000 (very close FR and phase response), PB12-NSD and PB-1000.

With the help of REW steering placement and phasing, we can help you make any of these subwoofers work - but obviously another identical model will have the same exact phase response and eliminate that variable from the equation.

Integrating dual subs is hard enough (even with REW) - and we try to avoid adding another layer of complexity with potential phase cancellation which otherwise wouldn't occur with the same brand/model as the 2nd subwoofer.

Why would two different models of subwoofer have phase cancellations that would be avoided with similar subwoofers?



And even if it produces different phase cancellations, why would it be assumed they would inherently be worse effects? Wouldn't you sometimes get better results depending on the room, placement and EQ?
 

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Why would two different models of subwoofer have phase cancellations that would be avoided with similar subwoofers?



And even if it produces different phase cancellations, why would it be assumed they would inherently be worse effects? Wouldn't you sometimes get better results depending on the room, placement and EQ?
When integrating dual subwoofers, it's best to have the same model for both subwoofers. This will eliminate the variable of introducing two different phase responses, which in my experience has never produced better results than two of the same subwoofer.
 
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