Official Power Sound Audio Thread.

[rpneuss]

Originally Posted by Goat1

I'm in awe at how tight the sound is with music. I still think it has something to do with being down firing. I was watching Ironman last night,I had my speakers all set to 80hz. Sounded absolutely awesome! The bass from that sub makes the system! I can't image what 2 would do.. I need to fire up Tron Legacy tonight after the football game. My brother is loving my Epik legend.

I used to not like iron man, that is, until I got a REAL sub. Now I watch Iron Man and start to smile. It has some excellent low lfe!

[Goat1]

I felt the same way about Transformers.. :P

[ALLIN]

Originally Posted by rpneuss

Follow Big Daddy's sticky quoted in Reilly's post at the top of the previous page.

Thanks for that thread. So it looks like it needs to be 120Hz cause theJman is talking about LPF on the speakers. It looks like the LFE (.1) just goes to sub and the LPF gets built into the LFE.

Variable Crossovers for all Speakers: The most modern AVR's and processors allow you to set different crossover frequencies for the front, center, side surround, and rear surround speakers. In addition, they allow you to set a low pass filter (LPF) for the LFE (.1) channel. Although these systems are more flexible and complex, they are not necessarily better and need some degree of expertise to be set properly.

Normally you set the LPF of LFE to 120Hz to make sure you receive all the information that the audio engineers put in the LFE channel. At the same time, you want to make sure that frequencies above 120Hz will not go to your subwoofer as it is possible that some discs, particularly older DVDs, may have a full-range LFE channel due to poor and careless engineering.



The LFE channel is an independent channel and has no effect on the other speakers. The information that is in the LFE channel extends up to 120Hz regardless of whether you have bookshelf speakers or full-range super tower speakers. It is important to distinguish between the LFE channel and what goes to a subwoofer. The LFE is a production channel, whereas the subwoofer is a playback channel. The sound engineers determine what goes to the LFE channel, and the users of the home-theater systems determine what ends up coming out of the subwoofer.

Thanks Again RPN

[rpneuss]

Originally Posted by ALLIN

Thanks for that thread. So it looks like it needs to be 120Hz cause theJman is talking about LPF on the speakers. It looks like the LFE (.1) just goes to sub and the LPF gets built into the LFE.

Variable Crossovers for all Speakers: The most modern AVR's and processors allow you to set different crossover frequencies for the front, center, side surround, and rear surround speakers. In addition, they allow you to set a low pass filter (LPF) for the LFE (.1) channel. Although these systems are more flexible and complex, they are not necessarily better and need some degree of expertise to be set properly.

Normally you set the LPF of LFE to 120Hz to make sure you receive all the information that the audio engineers put in the LFE channel. At the same time, you want to make sure that frequencies above 120Hz will not go to your subwoofer as it is possible that some discs, particularly older DVDs, may have a full-range LFE channel due to poor and careless engineering.



The LFE channel is an independent channel and has no effect on the other speakers. The information that is in the LFE channel extends up to 120Hz regardless of whether you have bookshelf speakers or full-range super tower speakers. It is important to distinguish between the LFE channel and what goes to a subwoofer. The LFE is a production channel, whereas the subwoofer is a playback channel. The sound engineers determine what goes to the LFE channel, and the users of the home-theater systems determine what ends up coming out of the subwoofer.

Thanks Again RPN

No problem! Just keep in mind if 120 hz is causing you to localize the sub you can lower it to 100 or whatever is your preference. By localize I mean you can close your eyes, listen, and be able to tell exactly where the bass is coming from. Now that I have better subs I'm probably going to do some tinkering this weekend as well! Ultimately you should set your stuff to where you like it the most but Big Daddy's thread is a GREAT guideline!!

[ALLIN]

Originally Posted by rpneuss

No problem! Just keep in mind if 120 hz is causing you to localize the sub you can lower it to 100 or whatever is your preference. By localize I mean you can close your eyes, listen, and be able to tell exactly where the bass is coming from. Now that I have better subs I'm probably going to do some tinkering this weekend as well! Ultimately you should set your stuff to where you like it the most but Big Daddy's thread is a GREAT guideline!!

Yes it was I have read Big Daddy's threads in the past. They are excellent.

That is where I have been running my subs at 120hz. With the dual subs it does a great job of not localizing the subs. I have read in the past that it is more of a problem with a single sub. But I think placement also has something to do with it.

Ok time to hand back the thread to PSA Subs. Thanks for indulging my hobby.

[Tom V.]

Two things make the 120hz upper end of the LFE channel less likely to be localized.

1)The sound engineer typically doesn't include much high level signal over 80hz on the LFE channel.

2)The filtering at 120hz is a "brickwall". Meaning there is no audible signal at 121hz or higher.

In all other context of this discussion (i.e...."where is the bass going")...the crossover points apply GRADUAL slopes to the signal. For example, if you have your center channel set to SMALL/100hz in your receiver's setup menu....the center channel is getting a LOT of signal under 100hz. Assuming a 12dB/octave slope...the signal will be down 12dB at 50hz. So at 80-100hz there is still a lot of info going to the center.

Conversely, the subwoofer in the example above will be getting...

1)the entire LFE channel(3-120hz).
2)the signal from the center channel with a 12dB/octave slope centered at 100hz. So The subwoofer handles most of the bass <100hz(from the center channel) AND it will even produce quite a bit of signal from the center channel ABOVE 100hz.

As a side note----this is why I personally feel it is very important for the subwoofer to extend well beyond 80-100hz in a relatively flat fashion.

Tom V.
Power Sound Audio

[rpneuss]

Originally Posted by ALLIN

Yes it was I have read Big Daddy's threads in the past. They are excellent.

That is where I have been running my subs at 120hz. With the dual subs it does a great job of not localizing the subs. I have read in the past that it is more of a problem with a single sub. But I think placement also has something to do with it.

Ok time to hand back the thread to PSA Subs. Thanks for indulging my hobby.

Placement is the key, you are correct! Acoustics of the room come into play too. The acoustics in my room aren't good and next on the list is room treatments. So do you have power sound subs?

[rpneuss]

Originally Posted by Tom V.

Two things make the 120hz upper end of the LFE channel less likely to be localized.

1)The sound engineer typically doesn't include much high level signal over 80hz on the LFE channel.

2)The filtering at 120hz is a "brickwall". Meaning there is no audible signal at 121hz or higher.

In all other context of this discussion (i.e...."where is the bass going")...the crossover points apply GRADUAL slopes to the signal. For example, if you have your center channel set to SMALL/100hz in your receiver's setup menu....the center channel is getting a LOT of signal under 100hz. Assuming a 12dB/octave slope...the signal will be down 12dB at 50hz. So at 80-100hz there is still a lot of info going to the center.

Conversely, the subwoofer in the example above will be getting...

1)the entire LFE channel(3-120hz).
2)the signal from the center channel with a 12dB/octave slope centered at 100hz. So The subwoofer handles most of the bass <100hz(from the center channel) AND it will even produce quite a bit of signal from the center channel ABOVE 100hz.

As a side note----this is why I personally feel it is very important for the subwoofer to extend well beyond 80-100hz in a relatively flat fashion.

Tom V.
Power Sound Audio

Great post Tom! Very well said!

[Goat1]

So set it at 120 and be done with it?

[rpneuss]

Originally Posted by Goat1

So set it at 120 and be done with it?

Try it in your setup and see if it works for you. If you don't like it bring it down to your liking. Tom pointed out that there isn't much above 80 hz in the lfe track but you could potentially be missing out on stuff above 80. Personally I feel my setup sounds great but I'm gonna play around myself.

[theJman]

Originally Posted by Goat1

So set it at 120 and be done with it?

For the LFE channel, yes. For the LPF, maybe.

LFE -- if your receiver even has such a setting -- should be configured for 120 Hz. The LPF used depends upon your speakers, and your personal preferences. Myself, I don't like it to be any higher then 80Hz. Some are OK with 100Hz, while others are fine with 120 Hz, but not me.

What are your other speakers, make and model? That would help determine what your LPF options are.

[mreilly611]

Originally Posted by rpneuss

Try it in your setup and see if it works for you. If you don't like it bring it down to your liking. Tom pointed out that there isn't much above 80 hz in the lfe track but you could potentially be missing out on stuff above 80. Personally I feel my setup sounds great but I'm gonna play around myself.

My personnel feeling is you have the LFE .1 track that goes to 120Hz. Go to 120hz to hear everything the way it was recorded. So please dont yell at me. It is a choice that works for me.

[theJman]

Originally Posted by ALLIN

I hate to start this debate. I know this is a Sub Thread. But All this info being spewed is making my head spin and I dont know who to ask. So Mreilly if you could please stay away from not getting involved. We dont need the back on forth. Thanks. I just have one question. On the example above you dont mention what the sub is set to or needs to be on and the same with the receiver LPF on LFE. 120Hz?

Are you OK with this concept now, or do you still need some assistance? You've gotten a lot of good advice already, so I wasn't sure if you needed anything else from me or you were good to go.

[rpneuss]

Originally Posted by theJman

For the LFE channel, yes. For the LPF, maybe.

LFE -- if your receiver even has such a setting -- should be configured for 120 Hz. The LPF used depends upon your speakers, and your personal preferences. Myself, I don't like it to be any higher then 80Hz. Some are OK with 100Hz, while others are fine with 120 Hz, but not me.

What are your other speakers, make and model? That would help determine what your LPF options are.

Great post Jman! I also found the crossover setting of 80Hz to be my fave! I'm not opposed to tinkering though so I might try bumping it up and see how it work! Are you running power sounds bro? I have some friends that want subs at a little bit smaller price point then what I paid for mine and these look great! Plus Tom seems to be very knowledgeable.

[ALLIN]

Originally Posted by theJman

Are you OK with this concept now, or do you still need some assistance? You've gotten a lot of good advice already, so I wasn't sure if you needed anything else from me or you were good to go.

I think Tom V gave a great explanation. With the if your Center is at 100hz as crossover you are still getting sound in center below 100hz with the 12db slope. And the rest is going to your sub built in to the LFE at 120hz.

The thing that is still a grey area is if the Sub LPF on LFE in receiver is set to 80Hz what happens to the full 120Hz LFE .1 to sub and the rest of the LPF from center with the slope. The Center is playing most of it but some of the signal would be dropped from the sub if LPF on LFE is at 80Hz? Plus with Toms statement below with Subwoofer to extend well beyond 80-100Hz does he mean on Sub (i think he said a day or two ago the sub frequancy should be turned all the way up) So I guess he means in receiver LPF on LFE setting should be set higher.

From Tom V

As a side note----this is why I personally feel it is very important for the subwoofer to extend well beyond 80-100hz in a relatively flat fashion.

Tom V.
Power Sound Audio

[Goat1]

Originally Posted by theJman

For the LFE channel, yes. For the LPF, maybe.

LFE -- if your receiver even has such a setting -- should be configured for 120 Hz. The LPF used depends upon your speakers, and your personal preferences. Myself, I don't like it to be any higher then 80Hz. Some are OK with 100Hz, while others are fine with 120 Hz, but not me.

What are your other speakers, make and model? That would help determine what your LPF options are.

I have Mirage OMD 15's,OMD C2 center,OMDR surrounds and def tech 8040 rears. If you don't know what they are,go to Vanns and you can see them.

[theJman]

Originally Posted by rpneuss

Are you running power sounds bro?

Sort of. My world looks like this...

[crazyBLUE]

Originally Posted by theJman

Sort of. My world looks like this...

If only they were all yours Right....

[theJman]

Originally Posted by ALLIN

The thing that is still a grey area is if the Sub LPF on LFE in receiver is set to 80Hz what happens to the full 120Hz LFE .1 to sub and the rest of the LPF from center with the slope. The Center is playing most of it but some of the signal would be dropped from the sub if LPF on LFE is at 80Hz? Plus with Toms statement below with Subwoofer to extend well beyond 80-100Hz does he mean on Sub (i think he said a day or two ago the sub frequancy should be turned all the way up) So I guess he means in receiver LPF on LFE setting should be set higher.

Adjustments for LFE and LPF are completely different, so don't group them together. Just consider them to be totally unrelated, regardless of the fact they both produce output to your subwoofer. If it's easier to envision pretend your subwoofer is hooked up to a pair of input sources, not just a single one. Even though the signal is received on just the one coax cable, there's actually two signals being sent. Independently (for movies, anyway, because music doesn't use the LFE .1 channel).

If your receiver has an LFE adjustment -- which is rare, because it's essentially useless -- you aren't setting a crossover with it, you're setting a cutoff. The distinction between the two is significant. When you set an LPF it's what Tom was referring to; a specific frequency where the sound starts to diminish. In his example it was 12 dB per octave. Think of the LPF crossover setting as a smooth and even decline, often referred to as a slope because that's what it looks like when you take a measurement. This setting affects your 5. (or 7.) speakers, and is the one you can set individually by channel.

The LFE setting, on the other hand, is a hard and fast limit. If you set it at 80Hz then there is no 81Hz, no slope, no gentle roll off. At 80Hz it's done. An LFE setting only affects the .1 channel, and nothing else.

Originally Posted by ALLIN

From Tom V

As a side note----this is why I personally feel it is very important for the subwoofer to extend well beyond 80-100hz in a relatively flat fashion.

All Tom means by this is that your subwoofer should have a clean and flat (measured) response above 100Hz so as the LPF crossover setting starts to switch the signal from the subwoofer to your speakers, and it begins to slope away, the sub still has enough usable frequency response to be able to handle the signal until it's rolled off so much it becomes inaudible. This generally occurs by -8dB to -10dB, but as Tom notes that could take a while to happen because of the slope so it's better to have a sub with capabilities beyond the LPF you set for the other channels so it can accommodate this phenomenon.

[theJman]

Originally Posted by crazyBLUE

If only they were all yours Right....

There are worse problems to have, aren't there?