Connecting Subs

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Brad225

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I purchased two more Depth I's and am going to see what 4 of them does for the low end in my room. The two current Depth i's are located on the side wall and are run as a left and right channel.
My preference would be to have 2 right and 2 left channels since the wiring would be easier. I will try running them as 4 mono running both L & R cables to each though it's twice as much cable for a permanent installation to run behind all of the acoustic panels.

Using a Y connector (as many people do) to combine the left and right channel seems like it would be seen by the preamp as a short between the channels. Am I correct with this thought process?

If you have any other thoughts on connecting 4 subs please speak up.
 
Yes you are correct.
A wye can always split.
But to use it as a combiner you need a little circuit.

See this Rane Note:

"Why Not Wye?"
Dennis Bohn, Rane Corporation
RaneNote 109 written 1991; last revised 4/04

Splitting Signals
Subwoofing in Mono
Unbalanced Summing
Balanced Summing
Output Impedances

http://www.rane.com/note109.html
 
I tried something novel, I opened the Depth I manual once again to see what ML said about connecting multiple subs and what do you know there was my solution. I ended up splitting the signal at the preamp and sending a left and right signal to the 2 closest Depth's and then used the Sub Out on those to the Sub In of the other two Depth's. That at least eliminated making two more cables and overall less to run behind the acoustical panels so they wouldn't be seen.

There is a very noticeable difference in the quality of low end with 4 subs. Still making adjustments by ear but I will set up the XTZ Analyzer at some point. I located them centered on all four walls and even though there is one behind my listening chair you don't hear it unless you turn the chair and focus on it. Currently running all 4 at 180 of phase compared to the mains and they crossover at 65 Hz. The volume on all the subs needed to be turned down exactly 50% from the setting I was using with 2 to be at the level I prefer. I'm not sure if this was a coincidence or if it was just a simple math calculation of twice as many speakers 1/2 the volume.

One of the things I found moving around the room is other than the corners the low end is much more controlled than before. With only one chair in the room everything was adjusted to that spot and if you moved around the room the bass would be over powering in some places. Now it is a much more even sound than I previously experienced.

With some more listening time I'm sure I will have more to comment on.
 
Sweet! Can't wait to hear it!

I'm planning on adding a 2nd BalancedForce 210 to my setup ASAP.
 
Brad, did the XTZ Room Analyzer help you dial in the subs?

I've ordered a 2nd BalancedForce 210, and will be grappling with bass integration issues once again! Between the various downloadable Summit bass profiles, plus ML's Perfect Bass Kit, and XTZ, I'll be busy for the next couple months experimenting with various bass permutations! I might need to pick your brain at some point (along with our SAS brethren <g>).
 
Alan, No I didn't use the XTZ. I basically started with the settings of the 2 existing subs. From there I started making adjustments to the phase, 25hz adjustment and crossover point. In the end, I believe I ended up with the same settings that I started with just lower volume on all 4 than 2.

Another thing occurred that I didn't expect. With the difference in recordings and presentation of the low end as the person mixing the music wanted, sometimes there is to much or to little bass for my taste. By making a very small adjustments to the volume control on the sub directly behind my listening chair the low end in the sound stage changes without anything noticeable anywhere else in the room.

Keep us updated on the 210 progress.
 
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