LPF of LFE

[krazeyeyez]

I was under the impression that the LPF of LFE setting on your receiver took priority as the crossover point, as in you could just turn up the crossover on your sub to say above 80hz if thats the setting on your receiver since your receiver would only send below 80 to the sub. This does not seem to be the case with my receiver, when it is set at 80hz crossover i can turn the crossover on my sub up and notice a difference in the sound to way above the crossover on the receivers point, so whats up with that?

[Audiophile_At_Birth]

Originally Posted by krazeyeyez

I was under the impression that the LPF of LFE setting on your receiver took priority as the crossover point, as in you could just turn up the crossover on your sub to say above 80hz if thats the setting on your receiver since your receiver would only send below 80 to the sub. This does not seem to be the case with my receiver, when it is set at 80hz crossover i can turn the crossover on my sub up and notice a difference in the sound to way above the crossover on the receivers point, so whats up with that?

It's suggested you leave the LPF of LFE at 120hz. Read this, as it's helpful for using Audyssey and it's setup with the speakers and subwoofers.

[BIslander]

All LFE gets sent to the sub regardless of the crossover. The crossover only comes into play with sound from the non-LFE channels. If you set the LPF on the sub to 80Hz, then any effects audio above that frequency will not be reproduced. As you raise the crossover on the sub, you will then be hearing the higher frequencies in the LFE channel.

When all speakers are attached to the receiver and not run through the sub, you want to disengage your sub's LPF or set it as high as possible.

[krazeyeyez]

@audio holics - i don't understand why the crossover would be set so high? it was my understanding 80hz was the general accepted level, and i know my speakers can drop at least that low, besides i would think setting it at 120hz would create distortion or problems when the sub is trying to produce tight high end bass and low deep bass at the same time with cone movement.

@BIslander - not following that? i mean what's the point of the crossover on the receiver AND one on the sub? My speakers are not ran through my sub, they are attached to my receiver, and the sub is attached to the sub out on the receiver. IF the crossover on the receiver directs everything below that, that would have gone to the other speakers to the sub instead, and turning up the subs crossover i am only hearing more levels of the lfe channel, i gotta ask what level a lfe channel usually goes up to, because i don't generally think of lfe at 140hz

[Audiophile_At_Birth]

Originally Posted by krazeyeyez

@audio holics - i don't understand why the crossover would be set so high? it was my understanding 80hz was the general accepted level, and i know my speakers can drop at least that low, besides i would think setting it at 120hz would create distortion or problems when the sub is trying to produce tight high end bass and low deep bass at the same time with cone movement.

@BIslander - not following that? i mean what's the point of the crossover on the receiver AND one on the sub? My speakers are not ran through my sub, they are attached to my receiver, and the sub is attached to the sub out on the receiver. IF the crossover on the receiver directs everything below that, that would have gone to the other speakers to the sub instead, and turning up the subs crossover i am only hearing more levels of the lfe channel, i gotta ask what level a lfe channel usually goes up to, because i don't generally think of lfe at 140hz

B. Raise the low-pass filter setting—usually incorrectly identified as a crossover—of the LFE subwoofer in the receiver / processor to 120Hz, if allowed.

..That was from the AVS thread. I've used both 80hz and 120hz and have never ran into distortion when trying to produce high and low LFE. With a LPF of 120hz, I have noticed you get more sub output, but this is understandable. To me, 120hz LPF sounds fuller. Plus I listen to a lot of music, more than I do watch movies. So in my case it works. However, in the end, you as the viewer and listener should choose the setting that sounds best to you.

[BIslander]

Originally Posted by krazeyeyez

BIslander - not following that? i mean what's the point of the crossover on the receiver AND one on the sub?

Yes. That's why I said the sub's filter should be disengaged or raised as high as possible if it can't be disengaged. You want the sub to output whatever LFE is on the source recording. And you want it to play whatever is sent from the receiver through bass management.

IF the crossover on the receiver directs everything below that, that would have gone to the other speakers to the sub instead, and turning up the subs crossover i am only hearing more levels of the lfe channel, i gotta ask what level a lfe channel usually goes up to, because i don't generally think of lfe at 140hz

EDIT: I believe LFE tops out at 120Hz.

Here was my point: if your equipment is working properly and you hear more audio from your sub as you increase the low pass filter above the AVR's crossover level, the only explanation is that you are hearing higher frequency LFE audio. It can't be redirected bass because you capped that at 80Hz coming out of your AVR.

[Yeha-Noha]

Some plate amplifiers, such as the one that drives my subwoofer, has a dedicated LFE input (single jack) in addition to the L and R inputs (dual jacks). Another name for LFE In is Direct In. Both are equivalent. I think Direct In is perhaps a less confusing appellation.

If I use the LFE input (Direct IN), the internal LPF is bypassed. It is intended to be used with A/V receivers having a single subwoofer output that combines both the LFE and the bass below the AVR's HPF (commonly 60 Hz - 80 Hz range when the speakers are set to small).

Some plate amps that don't have the LFE input, but only the dual R and L jacks, will require using a Y splitter from the AVR's subwoofer out. In this case, the internal LPF is active and it would be of utmost importance to set it to max or somewhere above the 120 Hz point in order to make sure that you don't cutoff any LFE. Of course if you have satellites crossing over at 160 Hz you would want to set the LPF well above that or at max to prevent a double crossover effect which might cause a hole or a hump in the output.

So if you have a dedicated LFE input or Direct In on your subwoofer, all you need to do is run an audio cable from your AVR subwoofer out to your subwoofer LFE in or Direct In and be done with it. No worrying about where the sub plate amp internal LPF is set to. This allows the receiver to control all the LFE and the bass from bass management processing going to the sub.

[blu1183]

im kinda new to this too if one of u experts can chime in here real quick

i got my cross over on my receiver set to 80
my LPF on the sub set to 160
my speakers set to small
phase on sub set to 0
sub decible set to 5

would u guys change anything? i dont know much about cross overs and frequencys lol.

[Yeha-Noha]

Originally Posted by blu1183

im kinda new to this too if one of u experts can chime in here real quick

i got my cross over on my receiver set to 80
my LPF on the sub set to 160
my speakers set to small
phase on sub set to 0
sub decible set to 5

would u guys change anything? i dont know much about cross overs and frequencys lol.

Those should be ok. I would set the LPF to max, unless 160 HZ is max on your subwoofer. That'll probably work though. It just needs to be above 120 Hz.

The 'sub decibel set to 5' doesn't mean much. A good starting place is about midway or slightly less. If you mean it's set to 5 db within the range from 0 db to 10 db, I think that would be good for starters.

[blu1183]

yes its 5db and the max is 10 on the sub and yes 160 is the max on my sub.

[Big Daddy]

Originally Posted by blu1183

yes its 5db and the max is 10 on the sub and yes 160 is the max on my sub.

The +5dB, +3dB, -4dB, etc. mean absolutely nothing. You adjust this level so that your subwoofer sounds approximately at the same level as the rest of your speakers at the main listening position. If you change the location of the subwoofer, this level will change.

[krazeyeyez]

thanks for the feedback guys, apparently i have had a huge bass hole for sometime now, i didn't realize lpf of the receiver was different then the lpf of the sub, i now have the sub cranked to max, and the receiver set to 80 along with all my speakers, and it does sound a lot better.

appreciated

[Big Daddy]

Originally Posted by krazeyeyez

thanks for the feedback guys, apparently i have had a huge bass hole for sometime now, i didn't realize lpf of the receiver was different then the lpf of the sub, i now have the sub cranked to max, and the receiver set to 80 along with all my speakers, and it does sound a lot better.

appreciated

Check A Guide to Bass Management thread that I created a few days ago. There are a couple diagrams there that may be useful.