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Anyone remember Velodyne? (2 Viewers)

JohnRice

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The answer to this is actually a little silly. Although the LFE channel should by spec only go up to 120hz, there is nothing stopping a mastering engineer from adding content above that frequency when doing the final mix. It certainly can't hurt anything to set it higher than 120 hz, while setting it lower is definitely bad. For that reason, I generally recommend setting it to the highest value possible just to be safe
That makes sense. No reason to not filter out something when it isn't there, but leave it when it is.
 

Steve Chomicz

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The (virtually) only time the way Polk describes would be the correct way to connect a sub is with an integrated system with a passive sub, where it contains the crossover specifically designed for the satellite speakers. Common in "computer" systems but almost unheard of in surround systems.

John, 2006 is a long time ago in the tech world. as your knowledge exceeds mine in this HTF area i have attached the polk audio subwoofer connection educational article from 2006. I have their RMS satellite speakers and on page 5 they say resist all pressures to use the LFE input port on your powered sub. let the sub do the work.

Can you help me out here and please read their reasoning? Maybe i interpreted it incorrectly. thanks.
 

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JohnRice

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John, 2006 is a long time ago in the tech world. as your knowledge exceeds mine in this HTF area i have attached the polk audio subwoofer connection educational article from 2006. I have their RMS satellite speakers and on page 5 they say resist all pressures to use the LFE input port on your powered sub. let the sub do the work.

Can you help me out here and please read their reasoning? Maybe i interpreted it incorrectly. thanks.
I’ll give it a look.
 

JohnRice

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John, 2006 is a long time ago in the tech world. as your knowledge exceeds mine in this HTF area i have attached the polk audio subwoofer connection educational article from 2006. I have their RMS satellite speakers and on page 5 they say resist all pressures to use the LFE input port on your powered sub. let the sub do the work.

Can you help me out here and please read their reasoning? Maybe i interpreted it incorrectly. thanks.
OK, so terms tend to get mixed up. The reason that document says not to use the subwoofer output from the receiver is because that sub doesn't have an LFE (direct) input. The ideal setup is to configure how low frequencies are distributed in the receiver/preamp's speaker setup, then send the frequencies designated for the subwoofer to it, and the rest to the various speakers. A sub's LFE input is specifically intended for this, because it doesn't do any frequency filtering in the sub. The problem is, the sub being referred to in that document doesn't have an LFE input. It only has filtered inputs, which creates problems. The document addresses how to work within those problems, but doesn't actually specify that the source of the problem is the poor/cheap design of the sub.

So, with a sub that has an LFE (direct, unfiltered) input, you configure everything in the receiver/preamp and use that input (LFE) from the sub output. If your sub doesn't have an LFE input, what you should do, ideally, is get one which does. If you can't do that, there is no ideal solution. You can do what that document recommends or you can still use the sub output and turn the LPF (frequency) setting on the sub all the way to the highest setting. Sometimes that will be OK and sometimes it won't. It depends on other variables.

Incidentally, often the LFE (unfiltered) input is activated with a switch. The switch in fact bypasses the low pass filter (LPF) of the sub's internal circuitry.

Does that answer your questions?
 

Steve Chomicz

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OK, so terms tend to get mixed up. The reason that document says not to use the subwoofer output from the receiver is because that sub doesn't have an LFE (direct) input. The ideal setup is to configure how low frequencies are distributed in the receiver/preamp's speaker setup, then send the frequencies designated for the subwoofer to it, and the rest to the various speakers. A sub's LFE input is specifically intended for this, because it doesn't do any frequency filtering in the sub. The problem is, the sub being referred to in that document doesn't have an LFE input. It only has filtered inputs, which creates problems. The document addresses how to work within those problems, but doesn't actually specify that the source of the problem is the poor/cheap design of the sub.

So, with a sub that has an LFE (direct, unfiltered) input, you configure everything in the receiver/preamp and use that input (LFE) from the sub output. If your sub doesn't have an LFE input, what you should do, ideally, is get one which does. If you can't do that, there is no ideal solution. You can do what that document recommends or you can still use the sub output and turn the LPF (frequency) setting on the sub all the way to the highest setting. Sometimes that will be OK and sometimes it won't. It depends on other variables.

Incidentally, often the LFE (unfiltered) input is activated with a switch. The switch in fact bypasses the low pass filter (LPF) of the sub's internal circuitry.

Does that answer your questions?
I did not catch that slight but important difference. ,thank you very much John for noticing it. as my sub has a an LFE input, I will rewire it. Do i keep my satellites as large or change to small when i switch wiring? and the 2 surrounds? I am going to update my entire system in 2021. technology moves so fast.

I owe you one. If HTF had a reward system like reddit I would give you gold for helping me.

Peace
 

Clinton McClure

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I did not catch that slight but important difference. ,thank you very much John for noticing it. as my sub has a an LFE input, I will rewire it. Do i keep my satellites as large or change to small when i switch wiring? and the 2 surrounds? I am going to update my entire system in 2021. technology moves so fast.

I owe you one. If HTF had a reward system like reddit I would give you gold for helping me.

Peace
Set all of your speakers to small.
 

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