Subwoofer Choice

[mike c]

you know and I know that the Fathom 113 is the greatest subwoofer known to man. before that was the DD18. before that was the HSU subs. before that was the Axiom EP500.

so until a new flavor of the month comes out ... the F113 is king.

 

[mike c]

alex, ignore my last post ... I'm just pulling mazers leg.

 

[mazersteven]

so until a new flavor of the month comes out ...

Introducing the "Flavor of the Month".

 

[Soundman]

How about 1 Ultra-13 instead?

Hmmm. Well, it would extend lower, but wonder what would give more impact. It would be cheaper to go with the Ultra-13 too. but then it comes down to, do you want 2 subs or 1?

 

[avaserfi]

Hmmm. Well, it would extend lower, but wonder what would give more impact. It would be cheaper to go with the Ultra-13 too. but then it comes down to, do you want 2 subs or 1?

Two subs won't give more impact than one good sub. The only reason I see to get two subs, over one better sub, is if you want to use the two subs together to flatten on your low end frequency response and even then you are just making a nightmare when it comes to placement, but it can be worth it. Besides the Ultra-13 is cool...

 

[annunaki]

Two subs won't give more impact than one good sub.

You can't be serious. With 2x the displacement and power, two subs will yield at or around +6db or more output than one, in-room. If they are well placed not only can they have more impact but also flatten in-room reponse reducing nulls. This will result in greater impact.

 

[avaserfi]

You can't be serious. With 2x the displacement and power, two subs will yield at or around +6db or more output than one, in-room. If they are well placed not only can they have more impact but also flatten in-room reponse reducing nulls. This will result in greater impact.

I knew about the nulls and the increased response but I thought were were comparing two lower end woofers to SVS highest end subwoofer. Then the story on output changes, doesn't it?

edit: It is two of these or one of these. Does the rule of thumb come into play even though the two subs perform differently? I figured the db change between going from two lower level subs to one higher would be nill or close to and the placement issues involved with this situation might be a little much for someone new to the hobby.

 

[annunaki]

I knew about the nulls and the increased response but I thought were were comparing two lower end woofers to SVS highest end subwoofer. Then the story on output changes, doesn't it?

edit: It is two of these or one of these. Does the rule of thumb come into play even though the two subs perform differently? I figured the db change between going from two lower level subs to one higher would be nill or close to and the placement issues involved with this situation might be a little much for someone new to the hobby.

I see where you are coming from, and it makes sense. Look at it this way. Say XYZ subwoofer displaces 40 cubic liters of air at full tilt. It is a top of the line sub. At that level it does 110db in room. However it is more susceptible to room nulls and peaks.

Take ABC sub, still of high quality (linear design) and the same, or nearly the same, driver size. It displaces 35 cubic liters of air at full tilt. At that level of displacement it does 106db in room.

Now, because we have two we should theoretically see an increase of about +6db (+3db for displacement increase x2, +3db for power increase x2) for a total of about 112db. However we are also now displacing 70 cubic liters of air, or nearly twice the amount, not to mention smoothing out room response making it much more uniform. Two of ABC subwoofer will have more visceral impact as well as (potentially) sound "better" because it achieves better in-room response.

Now if it is not done properly, and both subs are put into the one location (that the superior sub would be in) by all means it should sound better (superior sub).

The differences in subwoofers (within the same brand) becomes marginal as you go up the line. For instance, most people will not notice much difference, if any, between an SVS Ultra and a Plus. Simply, for the reason that our ears are not real sensitive to changes in the bass region.

Does that make more sense? I hope I did not go too far off the subject.

Edit I: I just clicked on your links. You would have a total of four 12" drivers to 1 13" driver. You will have substantially more output and visceral impact with the two "lower end" (I use that term very loosely) subwoofers. The only tradeoff with the ultra will be in resolution and detail as it should be a bit more accurate.

Edit II: In this actual case (upon checking the links) the displacement for each of the sub systems should be about equal if not a slight advantage in terms of the PB-12/NSD. Both are linear designs and will yield very good performance.