Help Hooking Up My Sub

Papete

Guys,

Went to Tweeter the other day to buy some cables to connect my new projector to my Bose 35 LifeStyle. The salesman was real good (and so was the sound) so I left the store with the following goodies rationalizing that I can sell the Bose on eBay and get a few of my dollars back!

Anyway here's what I'm trying to hook up and the questions I have of you folks:

A Dennon AVR3805 Reciever using the Polk RM20 5.1 package with a couple of Polk TC80i's as front left and right speakers giving me a 7.1 system. Since I'm hooking up stuff from different manufacturers (unlike the Bose) I'm really confused on how to hook up the Polk sub to the Dennon Reciever.

My guess is that I should run speaker wires from the reciever to each of the 7 surround speakers on the walls (already done) and run a RCA type cable from the back of the Dennon (Sub out jack) directly to the sub and ignore the speaker in and out connectors on the Polk Sub altogether. If this is correct here’s where I need your help:

1) Do I connect this RCA type cable to the yellow LFE jack on the back of the sub? (What does “LFE” stand for by the way and why the heck is it yellow like a composite video jack?)

2) Does this cable have to be shielded? (Boy I hope not because I can soldier plugs to the set of speaker wires I already ran through the wall preparing the room for the set up!)

3) Should I hook up the sub’s power cord via a long extension cord to one of the switched plugs on the back of the Dennon?

I’ll appreciate any and all help you can give me here. Thanks

Pete

McLoki

Originally posted by Papete
1) Do I connect this RCA type cable to the yellow LFE jack on the back of the sub? (What does “LFE” stand for by the way and why the heck is it yellow like a composite video jack?)

Yes this is where you want to connect the cable. The LFE jack should bypass the crossover in the sub. (you are now using the crossover in the Reciever (also called an AVR) and you only want to go through 1 crossover (sub or AVR but not both).

LFE, I believe, stands for Low Frequency Effect.

Originally posted by Papete
2) Does this cable have to be shielded? (Boy I hope not because I can soldier plugs to the set of speaker wires I already ran through the wall preparing the room for the set up!)

This depends on what else is running through your wall. Most sub cables are sheilded. You could try and use what you have, but if you get alot of hum from your sub, you may need to run a new wire.

Originally posted by Papete
3) Should I hook up the sub’s power cord via a long extension cord to one of the switched plugs on the back of the Dennon?

What sub are you using? (I am not familiar with much of the bose line - are you using the sub from that?) Anyway - many subwoofers have a signal detect feature that will automatically power on the sub when a signal is present. If you have one of those, just use it. You could also just leave the sub on. Your suggestion will work, but pay attention to
1. How much (max) current/watts will the sub amp draw?
2. Will the plug on the back of your AVR handle that amount of juice?
3. Will the extension cord that you are using be ok for that amount of draw for that length cable?

Originally posted by Papete
I’ll appreciate any and all help you can give me here. Thanks

Pete

Welcome to Club Polk. Have you hooked up your new system yet? How does it compare to your old one? There are many here who feel that bose is very expensive for what you get, I would be interested in hearing what you think of your new Polk system compared to your old Bose system. I am also curious what the cost differential was. (percentages are fine, Dollars are not really any of my business )

Anyway, I am sure others will be chiming in with suggestions or wanting more info.

Enjoy your system and happy holidays.

Michael

okiepolkie

Pete,

Welcome to the forum. Congratulations on your Polk purchase.
I know that some of these things have already been said, but I think I was typing the same time as McLoki.

With a 7.1 HT system, you will probably want to hook the subwoofer from the subout on the receiver to the LFE(Low Frequency Effects) on the subwoofer. This is an unfiltered input that utilizes the receiver's internal bass management instead of the subwoofer's.

A shielded cable is preffered so you don't get other "noises" bleeding into your subwoofer. Someone else might have a different opinion on this though.

It is not necessary to use an extension cord to plug the subwoofer into the outlet on your receiver. The sub should have an auto on/off switch that will turn the sub off when it does not detect a signal.

The last suggestion I have would be to invest in a Sound Level Meter from Radio Shack and a calibration disk(avia, sound and vision, digital video essentials).

Hope this helps. Enjoy your new system.

McLoki

One other thing I forgot to mention. Set all your speakers to small in the AVR and the sub to ON.

I believe that reciever has a variable crossover in it, I would set the crossover to 150hz to start.

Certainly play with all the settings and try different setups to see how they sound, but this should give you a good start...

Michael

Papete

Mike and Okiepolkie,

Thanks for your help. The Polk system comes with a powered sub. I called my guy at Tweeter and he said to run a shielded cable from the Reciever's red right post (Sub Out), to the white left chan on the Sub. Think I'll try Okiepolkie's suggestion first as the Tweeter guy didn't seem too sure of his suggestion. Besides, with a name like Okiepolkie- you gotta know your Polk stuff.

Regarding the Bose- I got it about 3 years ago and have enjoyed it. My room is 13 by 31 and the Bose just does the job. The Tweeter display was in a much bigger room with the Dennon and the Polks (5.1 only) and it was incredibly thunderous. Very impressed and can't wait to get my basement rumbling. I think I paid about the same for both but understand that the Bose 35 is cheaper now-a-days.

Thanks. I'll let you know how it sounds when I'm done.

Pete

Papete

Guys,

Thanks again for your input. Everything is all hooked up and purring.

The learning curve on the Dennon was a bit steep but I'm beginning to figure it out. It has sooooooo many input and output possibilities that it can be a bit daunting at first.

Plus you gotta get used to the time it takes a projector to warm up and aquire a signal and then cool off after you shut down the lamp before you can finally shut her down alltogether. You certainly don’t fire up the sustem just to watch a few minutes of the 10 oclock news!

I've still got to tweek it out a bit if I can just stop watching movies and fights on HBO. Need to get a bit more volume from the smaller speakers. I think the two TC80I's I'm using for the front left and right are a bit more efficient and tend to over shadow the rest of the system. In the set up menu I set the speakers to “small” and left the volume settings all the same then locked the system when I was done. Now I just have to open the manual (I hate it when I have to do that) and figure out how to unlock the Dennon and set the 5 smaller Polks a bit louder. Then I can report on the difference between the Bose and the current set up to you.

Okiepolkie- re your suggestion-

"The last suggestion I have would be to invest in a Sound Level Meter from Radio Shack and a calibration disk (avia, sound and vision, digital video essentials). "

I have a Radio Shack Analog dB meter- is that the same as a Sound Level Meter? And- I purchased the mike for the Dennon to calibrate the unit which went smoothly on set up. Is this what you wrote about when you suggested I buy a calibration disk? Let me know when you get a chance.

Thanks,

Pete

okiepolkie

Take a look at this thread I started a few weeks ago:Calibration

Tour has a link in the middle somewhere that shows what I'm talking about( or you can just go here)

It would definetely be a good investment for audio and video. If you decide you don't need it anymore, then it usually has a good resale value.

Papete

Guys,

All done and tweeked thanks to you guys and I think I'll keep the Polk/Dennon set up.

The Bose is very accurate and a bit simplier to use but it is a little light in its ability to get loud or to "thump" the room when necessary. The Polk speakers and sub really kick butt running under Dennon power and if you are watching Alan Jackson in concert you really feel like you're there in the room. I found myself almost clapping after each number until I realized I'm in my basement. Yep- think I'll keep her.

Have a Merry Christmas and thanks again foir your input.

Pete Hoffman

PS New email- dumped Verizon DSL for Net zero and the new email is workingbees@netzero.com. If you guys know how I can make that change for this board please advise. Thanks.

Willow

You do not want to run the power cord from the Sub into the receiver. Turning off the receiver can release a loud thump and could result negatively to your sub.

This is a sub sat sytem, you should run speaker cables from the receiver to the sub then from sub to speakers. you will not need shielded sub cable. then you will have to adjust the subxover.

Papete

Willow,

Thanks- that's how I hooked her up. Don't know how the sub knows when I power up the amp- but it does????

Also learned to keep my SAT reciever plugged directly into the wall so the dumb thing isn't always "aquiring the signal" every time I hit the ON switch on the Monster Power Strip.

About the only thing driving me a bit crazy it that some times the InFocus 4805 Projector has trouble finding the source I'm trying to feed it. I keep the Dennon set to my DVD #1 because it has DVI capability and I use it the most. But I'm also running componet cables to the Projector from the Dennon to feed in the SAT TV, DVD #2 (recorder), and my VCR.

I think in all this confusion the InFocus scans all those inputs and some how (about 1/3 of the time) I have to shut down the Projector. Then (with the source running) I power up the InFocus again and she finds the source and displays a great pic on our 4 x 8 home made screen. Seems almost human sometimes because the problem is not a continuous one. Probably should start a new thread with this problem but I just might have to resort to reading some of the manuals!! ughhhh

Have a Great Christmas and thanks for your Post.

Pete