Need Advice....

Grimster74

On my setup menu on my Sony STR-DA4ES Receiver there is a setting for the LFE HIGH CUT Filter which is set on STANDARD which is 120Hz. Can someone tell me what this setting means at what it should be set at. My options as far as setting it is from 40Hz to 200Hz in 10Hz steps. All spaekers have been set to small also, does this sound right. Thx. and any help will be greatly appreciated.

JohnnyCanEHdian

I recently bought the Sony STR DE985 myself, and just finished setting up my speakers. The manual gives the following description.

LFE High Cut Filter: Lets you select the cut off frequency of the LFE channel high cut filter. Normally, select "STD". When using a passive sub woofer powered by a separate power amplifier, it may be better to change the cut off frequency.

Not very clear on what it does exactly. Since i am using a powered subwoofer, i just left mine set at "STD", but i too am interested in a better description.

Grimster74

Done a little more research. Not only does it have the LFE HIGH CUT Filter but I also noticed that you have the option to set the Front, Center, Surround, and Surround Back speakers the same way, 40Hz to 200Hz in 10Hz increments. So would that mean that the LFE High Cut Filter is to set the cut-off frequency of the subwoofer. I'm so damn confused. What should all these spaekers be set at. Thx. again.

Dr. Spec

You have a better bass management circuit than most AVRs. It allows you to independently set the crossover frequency to the subwoofer for each channel, including the LFE channel.

I suggest you bookmark and read this article in detail. Then read it again to make sure you understand it completely.

http://www.hometheaterhifi.com/volume_9_3/feature-article-multiple-crossovers-9-2002.html

While the LFE channel can in theory go to 120 Hz, in reality there is very little LFE content above 80 Hz. Therefore, you could set the crossover frequency for the LFE channel to 80 Hz and it will be NBD.

Conversely, leaving it at 120 Hz is NBD either. If you leave the LFE crossover frequency at 120 Hz, you will be sure to capture and replay everything in that channel. The only thing you risk is localization of the subs IF some sound engineer does decide to mix in some 120 Hz content. I think it's a very small risk.

My advice is to set all your speakers to small, the subwoofer to yes, and the crossover frequency to 80 Hz for all 7 surround channels, and leave the LFE channel at 120 Hz. 80 Hz is the THX standard.

If you can alter the filter rates for the high pass and low pass, then I suggest 12 dB/octave for the high pass, and 24 dB/octave for the low pass. This is also the THX standard.

What is the status of your subwoofer order?

Doc

Grimster74

Thanks Dr. Spec., I always look forward to hearing your responce. I did exactly like you siad as far as setting up all my speakers. As far as ordering the SVS, wife has put her foot down. Told me she had no problem with me ordering the sub but only under 2 conditions. 1) Had to sell my existing subs, which will be gone tomorrow, another words, ALREADY SOLD... and 2) said she didn't like to idea of two subs do to the fact that the kids keep hitting the one sub to the left of the television with the computer chair so it looks like I will be placing a order on Monday for the SVS PB2-Plus.

dorokusai

Grim - Sorry I was late posting but the Dr. was in the house, so you have been taken care of. I know a good bit about Sony setup parameters....Physics Coder and I are like the ugly Sony ES stepchildren of the Polk Forum

Dr. Spec was right on as far as the settings go. You have alot of adjustability with the Sony AVR. You know how Sony likes to pack their goodies.

Early in my Sonyhood, I started with the standard cut for the sub, but found that some music bleeds into it.... in that I mean...some very low synthetic voices. Like when they push voices thru a low vocoder or digitizer. That's just what happened to me, you may experience no issues with a 120hz set.

Anyways, I have since just went reference standard, 80 hz and experienced no problems.

No adjustments are available for high pass, that would be nice, but Sony doesn't love us THAT much.

Congratulations on your up and coming SVS purchase, thats certainly a MAN's subwoofer.....perhaps my little 202 will morph into a big one.

Dr. Spec

Originally posted by Grimster74
Thanks Dr. Spec., I always look forward to hearing your responce. I did exactly like you siad as far as setting up all my speakers. As far as ordering the SVS, wife has put her foot down. Told me she had no problem with me ordering the sub but only under 2 conditions. 1) Had to sell my existing subs, which will be gone tomorrow, another words, ALREADY SOLD... and 2) said she didn't like to idea of two subs do to the fact that the kids keep hitting the one sub to the left of the television with the computer chair so it looks like I will be placing a order on Monday for the SVS PB2-Plus.

Good deal Grim. As I stated above and Doro confirmed, you can either go with 80 all around, or 80/120 LFE. I honestly don't think you'll hear any difference because again the LFE channel has very little content above 80 even though it is designed to go up to 120 if necessary.

As the hotlink says, THX studied thousands of DVDs and came to the conclusion that 80 was no problem on the LFE channel and that 80 all around was also the best number for larger bass capable speakers that have an F3 of around 50-60 Hz.

You will find the PB2+ to be an outstanding performer and you will save $500 over duals. Even in the stock tune, it will dig far deeper and cleaner than your 450's could ever dream of, and the output with all three ports open will amaze you.

I run mine with three ports open the SS filter set to 16 Hz, and that allows the sub to naturally peak around 21 Hz and then slowly trail off into the upper teens. If you set the SS filter to 25 Hz, you will "brick wall" the sub at 22 Hz. This setting is most protective of the woofs and if you are REALLY belting it out (I mean 115+ dB) then use this setting. Otherwise, try 20 Hz and 16 Hz and allow the sub to naturally extend deeper.

If you really want to bottom feed, plug a port and set the SS filter to 20 Hz or 16 Hz and this will substantially fatten the curve below 20 Hz. You will lose a bit of output, but upping the sub level 1.5 dB with the AVR works perfectly to compensate. Output with a port plugged is still prodigious. I've found only a few DVDs really benefit from plugging a port and these have genuine and significant subsonic content. Other than those few, the stock tune of the PB2+ will do justice to 98-99% of the DVDs out there.

The PB2+ is still somewhat backordered due to the absolutely incredible demand for this sub. TC-Sounds is working overtime to crank out hundreds and hundreds of dB-12 Plus woofs, and the enclosure maker is working day and night too. I would expect to wait a few weeks at this point, so you will be subless for a while. If you can, keep the 450s until the PB2+ arrives for a direct comparo. Otherwise you'll be going from memory.

I went through the same thing with the pre-orders on the 20-39PC+; I waited months after I sold my dual 350s and soldiered on with dual stacked Advent Large speaks with an external amp for my makeshift sub. It did pretty well actually, since the Advents are flat to 30 Hz, but I bottomed them occasionally.

Good things come to those who wait, though.

Doc

Grimster74

First off, I can't thank Dr. Spec and Dorokusai enough for all your valuable inputs. I'm just glad to see there is someone else in the forum thats a die hard ES fan like myself, felt like I was the only one out there. For Dr. Spec, I just placed my order for my SVS PB2-Plus. Said it should ship somewhere around 3 to 4 weeks, guess I can wait that long. Know the next question I have is, (you guys should have known) I'm running a Monster splitter from the SUB OUT to the LFE IN (Unfiltered) to the dual PSW 450's. I noticed on the SVS Amp, there is NO LFE IN (Unfiltered). How is that going to work as far as receiver settings. I guess I'm not exactly sure what the "UNFILTERED" really means. I know with the way my H/T is setup know using the "Unfiltered In" I CAN NOT adjust the crossover ON the SUB amp, I only have volume control on the amp. Does this sound right. If not, someone please tell me what I'm doing wrong.

Dr. Spec

Originally posted by Grimster74
Know the next question I have is, (you guys should have known) I'm running a Monster splitter from the SUB OUT to the LFE IN (Unfiltered) to the dual PSW 450's. I noticed on the SVS Amp, there is NO LFE IN (Unfiltered). How is that going to work as far as receiver settings. I guess I'm not exactly sure what the "UNFILTERED" really means. I know with the way my H/T is setup know using the "Unfiltered In" I CAN NOT adjust the crossover ON the SUB amp, I only have volume control on the amp. Does this sound right. If not, someone please tell me what I'm doing wrong.

The unfiltered input means that you are bypassing the filter on the subwoofers plate amp because you are filtering with your AVR instead.

When I say filtering, I mean you are allowing the AVR to perform all your high/low pass bass management and you are sending the sub an already filtered signal. All the sub has to do is amplify it.

You don't want the sub to filter an already filtered signal - this is commonly known as "double filtering" or "cascading the filters" and will result in a depression in the FR at that point.

On the SVS, use either the left or right low level input and set the filter switch to "Disable". This bypasses the sub's filter control and is essentially the same thing as Polk's "LFE Unfiltered" single input jack.

Congrats on the PB2+. I'm really looking forward to your impressions vs. your PSW450's.

Doc