How to use my extra sub?

bmisthhou

I was just given an extra sub. Unfortunately, the subs in my system are the only non-polk speakers. The front sub only has low level input, the new sub I was given (a KLH) has low level left and right input and output but only speaker level input (no output). My receiver does not have low level out for the rear. I wanted to use this sub to compliment my RT25's. Whats the best way to do this?

My setup:

Panasonic SAHE-200 Receiver
RT600 Fronts
CS225 center
RT25 rears

Also, if anyone is familiar with the Panasonic SAHE-200 receiver. I am still trying to find the best settings for this setup. I currently have the front set to large, center to small and rears to large (since I have it split to the forementioned sub at the moment). I have the receiver filter setting set at 150 (I can select 100, 150 o 200). I am assuming it only uses this on the speakers that are set to "small". Does this sound about right?

Thanks for any help.

izafar

I would advise you to use your second sub via LFE out on your receiver. For this you need to use a splitter Y RCA cable to split the signal for your two subs. If you KLH requires both the L and R inputs to be connected at the same time then you will be needing another Y Splitter cable. Also set yur rears as small.

bmisthhou

OK, I didn't even think of doing it that way. I guess I was thinking that if the rears produced some heavy bass, I wanted it to come from rear sub, but those frequencies are ambient and not really localized, I'm not sure what I was thinking there. I will try this this weekend and see how it sounds. Splitting the the signal into two doesn't hinder the quality of the signal getting to the subwoofers?

Forgive me if I am a bit naive, I'm still learning.

Thanks!

Dr. Spec

Run all the speaks on small at 100 or 80 if you can. Y splitter low level input to both subs. Calibrate each sub separately since they will differ in efficiency with the same input strength. Stack em both in one corner. Adjust final sub volume at the receiver.

bmisthhou

This is interestesting. You reccomend stacking them in a corner together? Ill also try this on the weekend. Looks like I'll have my hands full. Thanks for your help!

Dr. Spec

Yes, setting all speakers to small and having one source of low bass in the room often results in the best in-room FR from a bass standpoint. Multiple sources of low bass can cause standing waves and nulls in the room at key listening spots.

Calibrate all your other speaks first with an SPL meter. After calibration, don't touch the master volume level. Set your LFE level at the receiver to -3. Run one sub and use the plate amp volume control to set its SPL to about 3 dB lower than than the other surround speakers.

Shut that sub off and do the same for the other sub.

Turning on both subs should get you a net result of about 3 dB above the other speakers, which is where most people like it.

If you need to change the overall sub volume after that point, use the receiver to bump it up or down. But don't make gross adjustments with the receiver, only a few clicks in either direction from the -3 reference point.

bmisthhou

Great,

Ill do this tommorow. I plan on changing around my entertainment rack and replacing some generic s-video cables with some higher quality ones. May as well re-arrange the speakers as well.

I have an SPL meter and will take your advice in calibrating and placing the subs.

Thanks for your input!

STUFFMD

Hey Bmisthhou,
I did my setup the way you were thinking..I got a Psw 202 for free with the purchase of my LSIC. I hooked it up to my FX rears and put it behind my couch...There is plenty of info comming through the rear channels that the FX's obviously could not reproduce. It has been a nice kick in the **** especially with HT...So in my opinion and experience that's not a bad way to go.
My 2 cents.
Peace StuffMD

bmisthhou

Ok, I re-arranged my room a bit this weekend. I have both subs on top of each other in the corner. I also pulled my fronts closer in together and forward towards the listener to get them positioned more accuractly.

I went from the sub out on my reciever to the low level input on the KLH sub (left and right split with a Y). I then went from the low level out on the KLH to a Y to the low level in on the Kenwood sub (single input). I then calibrated each sub, one at a time. Since I was not splitting the signal at the receiver, I didn't have the dropoff in signal when they were both connected together. Once I calibrated them individually, then tested them on together, it was twice as loud as it needed to be, I then adjusted using my recievers sub setting to get it low enough.

Everything sounds pretty good, tho the bass seems a bit too muddled. I used sound and visions calibration DVD to run all the audio tests. The kenwood sub has no phase setting, but the KLH has a 0 or 180 setting. Im not sure whether to mess with this or not?

Also, am I getting any real use by having them both connected? I mean, if one of the subs is good enough to fill the room, is there any other real benefit to having them both connected.

Finally, I am assuming that once I set the rear to small (after I moved the sub from the high level on the rears) the receiver will send all the rear low level frequencies to the sub? The manual for the receiver described the "filter" setting (which is at its lowest setting of 100 right now) as the frequency at which the front low frequencies are sent to the sub, it says nothing about the rears. Im not loosing the lows which go to the rears, am I?

Thanks for your help.

Originally posted by Dr. Spec
Yes, setting all speakers to small and having one source of low bass in the room often results in the best in-room FR from a bass standpoint. Multiple sources of low bass can cause standing waves and nulls in the room at key listening spots.

Calibrate all your other speaks first with an SPL meter. After calibration, don't touch the master volume level. Set your LFE level at the receiver to -3. Run one sub and use the plate amp volume control to set its SPL to about 3 dB lower than than the other surround speakers.

Shut that sub off and do the same for the other sub.

Turning on both subs should get you a net result of about 3 dB above the other speakers, which is where most people like it.

If you need to change the overall sub volume after that point, use the receiver to bump it up or down. But don't make gross adjustments with the receiver, only a few clicks in either direction from the -3 reference point.

nellis8166

I too got a free PSW202 with my LSI purchase. I wired it up to my rears this weekend. Took a while to calibrate, but it was a great improvement. I put it right behind the couch which I like to refer to as the "g spot", in other words the best listening position. Great for SACDS and HT, adds an extra kick in the butt.

Regards,
Nat

scottvamp

It would have to be a very bass heavy active surround "movie" to actualy get some usage out of that setup Nat.
Witch surround "speaker" are ya pulling the signal from.
You will only be getting bass from that speaker and

---

you will have to set your surrounds to Large.
How does all this work for ya?

Dr. Spec

"Im not loosing the lows which go to the rears, am I?"

No, if the rears are set to small, the bass info for the rear channels will be redirected to the sub below 100 Hz.

Leave both subs at the same phase setting.

The benefit of having two subs running is lower THD and more headroom for higher playback.

If they sound muddled, then experiment with placement.

scottvamp

I think there is a benifit to having ten subs but that isn't the point.
If you have sub hooked up to the rear surrounds using speaker line method - it just does not work.
Are you losing the bass - it depends.
The reason for hooking a sub to rear speakers via line level is to get DISCRET bass that would be coming from your surround speakers. In theory it sounds good but near impossable to get to work.

nellis8166

I have my speaks set to small and my crossover at 100. It made a noticible difference to me. It is wired into my side surrounds. It works well in my ears.

Regards,
Nat

nellis8166

Oh yeah...what Dr. Spec said....