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Discussion Starter · #1 ·
As some on here know, I have a new Ultra and a SB-12Plus(which I will refer to as Rosie). I got a Y-adapter, which is hooked into the Subwoofer Pre-Out on my AVR. I have the Ultra and Rosie split off of that connection. I have had previous conversations about why that may hinder my Ultras performance if set up exactly like that. That is not what I am asking about here though.


For sake of convenience, and just to play with both of my subs at times
, I thought that I would leave this hookup for the time being. But I have a very technical question regarding splitting. If I have Rosie powered off, with everything connected as I described above, does the Ultra still get affected somehow by the Y-adapter splitting at the pre-out point? Or does having the one sub turned off enable the Ultra to get full benefit of the LFE as if Rosie was totally unconnected and out of the picture? Thanks.
 

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Wish I could remember my electronics, but you shouldn't have any problems. The amps have like 50k Ohm inputs. With two in parallel, that makes 25k. Input signal is in the range of 1 Volt P-P. So, current draw is minimal, making voltage drop also minimal. What might have a small impact is if you have the gain turned up on the subs and a low input signal. This would make a small voltage drop/gain be amplified by the sub's amp.
 

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There is no appreciable loss when splitting the line level output signal.


Ian
 

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Having two doesn't mean you have 70mm Dolby (Baby Boom). There are many ways this can be done many. Get a DCX2496 then you can really design into something.
 

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I run 4 "Y" splitters on one LFE out and have no issues with bass.


Bill
 

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With Rosie turned off she is going to suck all the signal away from Bertha.
 

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Quote:
I was told it doesn't change the signal at all

They are right, it does not change the signal.


Many of us with monster sub systems have split our line level signal several time ( I have 3 splitters).
 

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Discussion Starter · #11 ·
So am I crazy to be running the SVS biggest ported sub, the Ultra, together with their smallest sealed sub - the SB-12Plus?
 

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Quote:
Originally Posted by sourbeef /forum/post/15548407


So am I crazy to be running the SVS biggest ported sub, the Ultra, together with their smallest sealed sub - the SB-12Plus?

I don't think THAT is the reason I would call you crazy.



You will have problems integrating them as they have different FRs. If you blend them at the higher range, as the frequency lowers, the SB is going to fade out. That leaves the Ultra on its own. Unless room gain is your best friend, you will notice a lower output at the low end. If you balance them at the low end, then they will probably sound boomy as frequency rises and the SB adds it volume to the Ultra. Try to integrate them in the 40 to 60 hertz range then see how they sound through the whole FR.
 

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Discussion Starter · #13 ·

Quote:
Originally Posted by ransac /forum/post/15548471


I don't think THAT is the reason I would call you crazy.



You will have problems integrating them as they have different FRs. If you blend them at the higher range, as the frequency lowers, the SB is going to fade out. That leaves the Ultra on its own. Unless room gain is your best friend, you will notice a lower output at the low end. If you balance them at the low end, then they will probably sound boomy as frequency rises and the SB adds it volume to the Ultra. Try to integrate them in the 40 to 60 hertz range then see how they sound through the whole FR.

I am a newbie at all this. Are you saying the low frequency output of the Ultra will be lesser because of running them together, and I would be better with just the Ultra running for the low end, highest decibel output?
 

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Discussion Starter · #14 ·

Quote:
Originally Posted by ransac /forum/post/15548471


I don't think THAT is the reason I would call you crazy.

say WHAT????????
 

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Quote:
Originally Posted by sourbeef /forum/post/15548602


I am a newbie at all this. Are you saying the low frequency output of the Ultra will be lesser because of running them together, and I would be better with just the Ultra running for the low end, highest decibel output?

What I'm saying is, both subs don't have the same FR and one goes lower than the other. When the one that won't go as low gives up, then you no longer have the combined output of both. But, your room gain down low may compensate for this loss.
 

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Discussion Starter · #16 ·

Quote:
Originally Posted by ransac /forum/post/15548794


What I'm saying is, both subs don't have the same FR and one goes lower than the other. When the one that won't go as low gives up, then you no longer have the combined output of both. But, your room gain down low may compensate for this loss.

thanks, I get it now
 

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Quote:
Originally Posted by sourbeef /forum/post/15548899


thanks, I get it now

Are you sure? Cuz I know you've heard it before.
 

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Quote:
Originally Posted by sivadselim /forum/post/15549519


Are you sure? Cuz I know you've heard it before.

I think I've heard it before, and I think I'm getting it, but just let me try here:


With an Ultra-13 and a SB12, and a single sub-out from receiver, one should:


- set receiver crossover in the 80-100Hz range


- use a y-splitter on receiver-sub-out


- use a 50Hz FMOD high pass filter on the line to the SB12 (this is where I'm not sure if I get it, if you want the SB to cover 50-100 and PB13 to cover 0-50, or would the 50Hz filter give about a 40Hz crossover, or ???)


- set the crossover on the PB13 to 50Hz (or would that be 40Hz)


Do I get it
If not, please clarify



One other question though. In this setup, if the two subs are not exactly the same distance from main listening position then some form of delay is need on one. Is this best achieved with a delay line (and what makes are available) or can phase adjustment on the subs take care of this?


Thanks
 

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Quote:
Originally Posted by rick240 /forum/post/15585751


I think I've heard it before, and I think I'm getting it, but just let me try here:


With an Ultra-13 and a SB12, and a single sub-out from receiver, one should:


- set receiver crossover in the 80-100Hz range


- use a y-splitter on receiver-sub-out


- use a 50Hz FMOD high pass filter on the line to the SB12 (this is where I'm not sure if I get it, if you want the SB to cover 50-100 and PB13 to cover 0-50, or would the 50Hz filter give about a 40Hz crossover, or ???)


- set the crossover on the PB13 to 50Hz (or would that be 40Hz)


Do I get it
If not, please clarify

So what you want is for the SB12 to do 50Hz to 100Hz? And the PB13 to do 50Hz below? If yes, I suppose what you said sounds about right.


I don't see anything wrong with overlapping a small span of frequencies (10Hz interval) because there is roll-off.


Btw, I am pretty sure using an FMOD HPF would not exactly cut-off at the indicated frequency.
 
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