LFE or speaker level?

AdamRagland

so i have had this question on my mind for a couple days. do you guys think its better to use the LFE input for your sub or speaker level? i have heard good arguments for each. I have done both but not in the same room so its basically useless. my primary use is HT. i have also heard that if you go speaker level, you don't get the LFE track from your movies. however! I have also heard that if you set your sub to "off" in the receiver it will send the LFE through speaker level. just dunno which to believe. anyone have any experience with this?

McLoki

If your main speakers will play at least down to the crossover point of your AVR (preferably a little below it) I like using a Subwoofer cable best.

If they will not - speaker cable is where you need to be.

Michael

All just my opinon of course...

psb962

I had the same question to answer last weekend. In the past I have always used the LFE but my new RTi10s were proving difficult to marry up with. I guess it depends on whether the crossover in your sub is better than the one in your AVR. I have a Onkyo 502 AVR:( and HSU STF-2 sub:), so I went with the speaker option after concluding that the sub crossover was better.

With speakers crossed over by sub, and with sub off in AVR, surrounds and center crossed over to fronts in the AVR at 80 Hz, I set it up as follows:

Full bandwidth pink noise, sub crossover to maximum, adjust sub vol until it 'blends', then reduce sub crossover freq until once again it blends. I found the result of that was a bass level that was mildly too strong, so I turned it down a fraction, and I'm done!

John K.

Adam, yes if you set the sub to "off" in your receiver the LFE effects in movies(when present)will go out the main speaker terminals along the speaker wire and into the sub amp, so this won't be lost if you use the speaker level connection. Nevertheless, the use of the sub out on the receiver into the line level input often labeled LFE on the sub allows for more precise bass management at the frequency set in the receiver than can be done with the speaker level connection.

PSB, if you've reached a result which satisfies you, that's fine, but keep in mind that the internal sub adjustment isn't a full crossover. It's only a low pass filter which rolls off the sub(roughly)above the selected frequency, but has no effect on the main speakers(even if they're connected through the sub), which continue to run full-range.

psb962

John K. wrote: »

PSB, if you've reached a result which satisfies you, that's fine, but keep in mind that the internal sub adjustment isn't a full crossover. It's only a low pass filter which rolls off the sub(roughly)above the selected frequency, but has no effect on the main speakers(even if they're connected through the sub), which continue to run full-range.

John, I didnt know that, but it certainly explains a few things that had me puzzled. Thanks for the insight. I'd been playing around with the SPL meter and the AVR's crossover for days and finally this hookup and the full bandwidth pink noise tweaks made it all come together. Guess I'l leave it alone now...

grateful72

Thanks for all the info guys. Good thread for newbies like me. I do have a question or two though.

Here's my setup. I just got a set of RTI speakers b/c of Fry's super discount .
RTI6's for front left and right speakers
RTI4's for surround.
Older Onkyo 5.1 Receiver.

I have decided to turn subwoofer off on my receiver and use speaker wire inputs to my sub because it seems to be louder and clearer vs. the subwoofer out. Plus, thanks to the help on this thread, I learned that all subwoofer sound (even LFE) gets directed to front speakers as long as center and surrounds are set to "small" and subwoofer out on receiver is turned off. Based on this setup, my RTI6's get the full range of sound from my DVD/CD/FIOS TV Box (including LFE), since I am using speaker level inputs for my sub.

Now here are my questions:
Are the internal crossovers in the RTI6's setup to harmlessly roll of sound below their rating (I think 55hz), or am i potentially causing damage to my new speakers by sending all this bass to them?

If I could be causing damage, is there some sort of passive High-pass filter/crossover that I can put in between the subwoofer and the front left and right RTI6's?


I am use to car audio, so please excuse me if these questions are dumb.

Thanks in advance.

psb962

I dont think you need worry about sending bass to your Rti6s. Every speaker used without a sub gets the same treatment. It would only be a problem if you fed them too much wattage, or a clipped signal. Either will damage a speaker. If you set your sub volume, and crossover, using full bandwidth pink noise at the level you'd like to listen at, then the bass coming out the sub will be nicely blended with the RTi6s. With the system set up properly, the risk of you cranking your amp so far up that it blows the speakers is low.

obieone

I just picked up some T90EB's(A.K.A. Monitor 60's) and tried them with LFE OUT(unfilered) in to my PSW303. I discovered from my user manual for my Denon 1905/785 that IF you set LFE-norm to LFE+Main you can do the same thing as wiring your fronts thru the sub. The only drawback is you should have actual LARGE speakers. I set the crossover to 60,80, and finally to 120hz, which gave it the most balance. Anything lower & it sounded too high. This works for me?!.
If you've got some beefy bookshelfs (RTi6), you can probaby get away with it, BUT you'll have to set them to large. It's the same thing as running your fronts thru the sub, only the processor does the work instead of running extra wires.
good luck.

Erik Tracy

The only 'problem' to using the sub out on the AVR to a powered sub is that some HT AVRs (like mine) have a 'stereo' mode for when you simply want to listen to LPs or CDs as they were recorded and meant to be listened without any additional DSP by the AVR.

When you select this mode (sometimes called "direct", "pure direct", etc), if you have your sub connected via the LFE input - then the AVR will NOT send any bass signals to your sub in this mode!

If all of your listening is 5.1 or when listening music you use the effects settings - then you're ok.

If you set the sub up the "Polk Way" you may find that you can do both!

That's what I'm going to try this weekend.

I was shocked/disappointed that having my PSW303 hooked up using the LFE connection meant that when I went "pure direct" on my AVR for listening to LPS there was no sound coming from the sub!

So, I'm going to switch the setup and go the "Polk Way" then set my speakers to Large with NO sub.

Erik