View Full Version : Dual Subs


copelanm
03-01-07, 07:24 AM
I have a question and please forgive my lack of knowledge.

Does using two subs have any advantage?


Will connecting one with the in line connections to the fronts and the other with the LFE RCA connection give better results? Or should they both be connected with a RCA splitter? I have very limited knowledge, but thought it might give more flexibility to control the Sub's crossover on one and then let the Reciever deal with the LFE variable (assuming the reciever has bass management capabilities)? Somebody straighten me out please!

mhsens
03-01-07, 08:22 AM
Does using two subs have any advantage?

This question is asked on average about once a week, so you may not get a full answer this time. I find the search feature difficult to use as well. Too many answers come up.

In sum, 2 is better than 1. But if you haven't yet purchased the 2, it's often preferred to spend the money on 1 better quality unit. If you already have the 2, use them both.

Which leads to the unasked question of where to place them. Stacked together. Or in different locations with the risk of phase cancellation, but the possible benefit of naturally smoothing room modes. Suggest you search that issue. I don't think there is 1 answer. Just pros and cons.

Will connecting one with the in line connections to the fronts and the other with the LFE RCA connection give better results? Or should they both be connected with a RCA splitter? I have very limited knowledge, but thought it might give more flexibility to control the Sub's crossover on one and then let the Reciever deal with the LFE variable (assuming the reciever has bass management capabilities)?

Much more complicated question. If your fronts don't have sufficient freq response to meld seamlessly at the system-wide crossover point with the main subwoofer, then I guess there is a benefit to sending a full range signal to the mains, but send that speaker level signal through the 2nd sub's high pass crossover before getting to those mains. But if that was your goal, I would just replace my mains.

Maybe there are other possible benefits as well. Although I use subs for this purpose (actually 1 sub for each of my rear speakers), it's only because I have extra subs sitting around. I wouldn't recommend it. And I only do it on a secondary Ht setup, where I just don't care and it just looks cool. I try to run all my subs through line level, via a Y connector or subwoofer processor. But that is a conservative approach that might come from ignorance.

copelanm
03-01-07, 09:59 AM
Searching and finding answers is tough to do. I'm not as technical as most people here. I appreciate the answer. I had an extra sub given to me (JBL E150 i believe) and thought I would use it. My system is low budget (I dont use it enough to justify the upgrade yet) and this sub is actually an improvement. If anything it will replace my current Polk sub. Thans for the answer.

Nuthed
03-01-07, 02:44 PM
I have a question and please forgive my lack of knowledge.

Does using two subs have any advantage?


Will connecting one with the in line connections to the fronts and the other with the LFE RCA connection give better results? Or should they both be connected with a RCA splitter? I have very limited knowledge, but thought it might give more flexibility to control the Sub's crossover on one and then let the Reciever deal with the LFE variable (assuming the reciever has bass management capabilities)? Somebody straighten me out please!
For years and years we were all told "bass is omnidirectional, it doesn't matter where you put the sub". Now, years later we are told "for uniform room response the sub should be placed carefully"....not just shoved in the corner or behind the couch. Later yet...."for optimized bass you need a sub in every corner to knock out standing waves".

Wouldn't turning up the sub level suffice for most people?

JimP
03-01-07, 04:29 PM
For years and years we were all told "bass is omnidirectional, it doesn't matter where you put the sub". Now, years later we are told "for uniform room response the sub should be placed carefully"....not just shoved in the corner or behind the couch. Later yet...."for optimized bass you need a sub in every corner to knock out standing waves".

Wouldn't turning up the sub level suffice for most people?

Not any more than driving faster would make stop signs go away. :rolleyes:

Nuthed
03-02-07, 10:59 AM
Not any more than driving faster would make stop signs go away. :rolleyes:
I fail to see the comparison. But if it makes you feel good to have more than one go ahead. My single M&K excites my room, actually my house, very nicely.

JimP
03-02-07, 11:08 AM
I fail to see the comparison. But if it makes you feel good to have more than one go ahead. My single M&K excites my room, actually my house, very nicely.

Here goes.

Turning up the volume of a subwoofer is like driving a car faster. Just because you drive a car faster doesn't make stop signs (nulls) go away any more than turning up the volume of a sub, corrects nulls in a room.

Have to admit, it was a bit out there.

vitod
03-02-07, 11:33 AM
Dual subs boost SPL and headroom. The subs won't be working as hard as a single sub. Plus they'll even out the response. But a single sub can can be enough for you. It all depends of your subwooferlism. ;) I love high impact, strong SPL, scary bass. :D

copelanm
03-02-07, 01:49 PM
How do you hook two up? Is it better to use the line level connection for both and set the fronts to "Small" at the receiver? Or is it better to run the fronts through the crossover of one of the subs, and use the other for the LFE? I'm about 2 days from running wire and need to know the best way to do it. I've searched and read this forum and can't find a straight answer. All answers have too much tech data for me to understand.

vitod
03-02-07, 03:29 PM
How do you hook two up? Is it better to use the line level connection for both and set the fronts to "Small" at the receiver? Or is it better to run the fronts through the crossover of one of the subs, and use the other for the LFE? I'm about 2 days from running wire and need to know the best way to do it. I've searched and read this forum and can't find a straight answer. All answers have too much tech data for me to understand.

You have two easy options.

1. Connect a Y-splitter from the receivers sub out, but make sure you have connections for both subs.

2. If the subs have plate amps, and have RCA signal outputs, connect a RCA cable from one sub's output, going into the others sub's input.

Ferres
03-02-07, 09:40 PM
I use my 2nd weaker sub for the rears. I find some movies still throw some low frequencies to the rear channels. Get some blast impact going from the front to the back. :)

You'll need Y-connectors for this, connecting with the surrounds.