Where to x-over? Sub or receiver? (1 Viewer)

[John_Bilbrey]

Which component is preferred for doing the crossing over, the sub or the receiver? I just got a JBL PB-12 (even my wife likes it!) and am using the crossover on my JVC 9010 set at 80hz, with the crossover on the sub set as high as it will go (around 150hz). I don't think that there is a way to defeat either of the two crossovers, so which one should I set to around 80hz? The receiver is only adjustable to 80, 100, or 120. The sub has a rotary knob adjustable from 50 to 150hz. Also, does it matter if I've only got one RCA going into the sub from my receiver's sub out? Should I get a splitter and run it into both the L and R on the sub? The manual says it doesn't really matter, but seems like I read on here that it tends to work better with both inputs in use. Thanks!

 

[Heath_R]

IMO you have it set up the best way. Crossover on the reciver, and turn the x-over on the sub up all the way to take it out of play. I am only using one input on my SVS 20-39PC and have no problems, I don't know about your sub though.

 

[Barry Barnes]

From what I have read, it sounds like you have it hooked up correctly by using the Xover in the receiver and turning the subs Xover up all the way.
As to the input question, I have seen cases where looping the input into both L & R increases the input level and thus makes the Sub go louder at a lower setting on the subs volume knob.
On some crossovers (like the X-30) this will mess up the "phase" correction rendering it useless. Most times the phase input for a single sub will be marked. I chose to just use one of my inputs for this reason and there is still plenty of "crank" left.

 

[Dustin B]

The way you have it is best. Also remember that most plate amps have a variable lowpass but a fixed highpass filter. In other words although you can very the sub lowpass filter that feeds the sub from 50-150hz, the signal sent the speakers will be a low order highpass filter fixed in the 120-130hz range.

 

[steve nn]

I did do the Y with my sub.When it is in the auto mode it comes on easyer and does require me to tone it down a bit more.I have the Vel-ct.150.So using the Y method in my case does increase gain or volume.I have seen other posts where this has been the same conclusion.It is not needed though in my limited understanding.

 

[Paul Clarke]

Hello John,

I have the PB-10 and wondered the same thing about connections. So I went to Rat Shack and got a Y. My sub level is now down to 9:30-10:00 clock position. Used to be 11:30 or so. This was back when I also was running a JVC receiver. Now it's strictly H/K.

80Hz is THX but that really is a goal to shoot for as most systems and set-ups have their own peculiarities. With your particular speaker set you may find better blending higher up.

 

[Kenny Booth]

I have a PB10 sub, I think all the controls are the same.

Flip the LFE/Normal switch on the sub to LFE and the subs xover IS bypassed. Flip the switch to normal and the subs xover works but I think then you will be going thru two xovers (AVR & Sub)

For some reason my sub sounds much better with the switch set to normal. I know this makes no sense and it goes against all directions but it works better for me.

 

[Steve_Ma]

My expereince FWIW:
I spent over a year and a half using the rec's (fixed 100hz) x-over and the LFE out connection. I am now experimenting with using my sub's x-over to optimize my 2ch performance. Here is my current setup.
* Sub hooked up via speaker level connections.
* Mains hooked up to sub's speaker connections so the sub is doing the filtering (currently at 60hz).
* Mains set to large and sub = no in the rec.
* Center and surrounds set to small.
Calibration is alittle trickier as you need an external test disk with various tones (www.stryke.com). Wiring is more of a hassel than I expected, but it's still a worthwhile experiment. Also, you will waste a minor bit of power with this setup, which may or may not be noticible depending on your room and equipment. For me, it has not been an issue.
If your setup is only for movies and/or you have bookshelf mains with a limited range, I would not bother. Overall, I'm pretty happy so far, though I am still tweaking alittle. But my 2ch performance seems better. I have noticed no difference for 5.1 movies, as my AVR will now send all LFE material to the mains (where it is filtered by the sub). Also, with the center and surrounds set to small, anything below the (rec's) 100hz x-over is sent to the mains and treated accordingly.
Anyway, I hope this helps.
--Steve

 

[John_Bilbrey]

Paul, did adding the Y adapter help? I noticed you said that you lowered the gain on the sub amp after adding the Y and switching receivers. Did you try the Y with your old receiver and did this make a difference?

Here's my setup:

JVC 9010VBK, using sub out to JBL PB12

Kenwood 3-way towers, 10" woofers

BA CRC center

BA VRS Micro surrounds

The sub out from the JVC is running into the L low level RCA input on the sub, LFE switch on sub is ON. Crossover dial is all the way to the right (150hz). Amp gain is in the 12:00 position. Keep in mind that this will be a 50/50 music/HT setup.