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LPF for LFE .....yes!!!!! :)

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#1 · (Edited)
LPF of LFE .....yes!!!!! :)

Like the title says ...LPF of LFE (for the .1 channel that is) and I'm loving it!!

I forget what thread I was reading a week or so ago in the bass section, but I came across a brief discussion of setting the LPF on the LFE channel at different Hz instead of the normal default of 120Hz.

IIRC, @Marc Alexander or @mthomas47 was saying they liked a 100hz setting, splitting the difference between 80 and 120hz.

So it got me thinking, why in the heck haven't I ever tried this!? I think I've mentioned on here before that I'm an avid demo'er. Meaning I use my system a lot for demoing various movie clips. I do this almost daily if I can fit it in. I've got lots of lossless MKV's Blu Rays on an external USB 5 TB drive making it very fast and easy to skip around to whatever part of a movie that I want.

I watch a lot of full movies as well (mainly at night) but since this demoing is pretty much how I get my bass fix on a regular basis, I'm always looking for ways to maximize the experience, at least for TR and Slam (while still feeling real & natural) for these brief 30-40 minute sessions at pretty sane master volume levels (usually around -6 to -15mv depending on the movie clip and my mood) to hopefully not kill my ears over time.

Probably like most of you HT bass lovers around here, I love and crave that tactile, visceral, hard hitting bass that you can seriously feel. In the past when I wanted more of it, I used to find myself overly bumping my sub trims to the point of it becoming to boomy and ear assaulting, listening louder than was comfortable, or both just to get more slam. I've had to find ways to try to get the best of both worlds. So over the last couple of years I've tried just about everything I can think of to maximize the bass in my system for this, involving FF subs + multiple NF subs right behind me + Crowsons and Buttkicker LFE's. I've tried numerous tweaks like different curves with PEQ for the FF and NF each on there own and combined as a whole through DSP with a miniDSP, how much each contribute in different areas, different crossover settings and even the phase trick to purposely run out of phase a little bit at certain frequencies to increase TR and Slam while minimizing SPL, Optimum Time alignment between TT/MA's and subs with the help of VibSensor, etc.

So I can't believe I've never tried messing with the LPF in the LFE channel until now! I think it's safe to say I most definitely like the setting lower than the default at 120hz. I've tried everything in between 80-120hz and have pretty much settled on 90hz, also where I have all my crossovers set. To my ears it's a fair amount more cleaner sounding (some movies more than others). Other than when I used to sometimes bump my sub trims way to much trying to get more slam, I've never really thought my system ever sounded bloated/muddy/mushy or whatever you want to call it, even with still running my subs pretty hot, But oh man ...I think the bass definitely feels and sounds cleaner, tighter and punchier now, while at the same time being able to run my sub trims about 1db higher, which = more TR and Slam while sounding cleaner :) 1db might not sound like a lot, but it does help maximize TR and Slam while keeping that equilibrium just right and not sounding to bass heavy compared to the rest of the frequencies. Especially when your running the subs pretty hot. Depending on the clip, I'll usually run them anywhere from 10-20db+ over the speakers (no DEQ). I find that some movies just need a bit different sub trim levels to totally maximize the experience. Since my external MKV file system is not to fancy, I just make a note of the sub trim levels used for that particular movie in the file name. That way when I revisit all my favs, it's perfectly set to my liking or if I make any bass tweaks, it's usually pretty easy to hear and feel what I've done and the way it effects various clips that I'm real familiar with.

So anyway, you may or may not care about all this crap, but I'm so excited I had to tell somebody about it, might as well be to my AVS forum friends right!? haha If I tell my wife about it she usually just rolls her eyes. Occasionally though she'll humor me and listen for a little while LOL

Where do most of you guys set your LPF of LFE at? Do you ever find that 80hz is a tad to lean sounding or 120hz can be a bit to much? I've read in a few threads (now that I'm more aware of this) that sometimes much over 80hz in the LFE channel can tend to be a bit mushy sounding. I think I've seen where Mark Seaton and a few others have mentioned this.

I intended for this to be a quick short post but got a bit carried away as usual :)
 
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#3 ·
I don't get it! I don't see anywhere to adjust the crossover other than setting them at 80hz. I thought the sub output automatically picked it up from there?

Sent from my SM-G950U using Tapatalk
 
#4 ·
Its not really a crossover, it's just in the .1 (LFE subwoofer) channel of your 5.1, 7.1 or whatever configuration you have in your system. It's the bass that is mixed for the .1 channel only, not the bass that is redirected to your subs at your crossovers settings from your speakers. There should be a setting in your AVR that will allow you to change the settings labeled LPF for LFE (Low Pass Filter for Low Frequency Effects). Most AVR's allow for 10hz changes: ex 80hz, 90hz ,100hz, 110hz, 120hz, Bypass, etc. I think most default it to 120hz but can be changed. Where ever you set it at, bass above this point will start to roll off.
 
#5 ·
Ohh I see. I've just never seen anything other than the settings for small or large. In small I set my A9's at 80hz. My AVR is the Yamaha 1060. Maybe I missed that setting somewhere.

Sent from my SM-G950U using Tapatalk
 
#6 ·
I've found no higher than 90hz is the sweetspot in my setup especially with Atmos material with 80hz giving the best sound on the deeper bass passages (fly over to the landing platform in the opening scene in Star Wars now Episode 2 is a good test but be warned the asteroid field rocks at 100 to 110hz and will make you want to leave it there!)

Did this a few years back and made for a fun afternoon with profound playback contributions.
 
#7 ·
I've always used the 120hz setting because that is what the Audyssey folks say. The content in that .1 channel only goes up to 120hz. But, if we crossover our mains at 80hz or less to avoid localization, why would we want the LFE effects between 80 and 120hz to be localized? I guess the choice is either localize them or leave them out, which is what you do when you lower the LFE LPF.

I may try it. I am not a fan of being able to spot my subs.
 
#11 ·
I guess the choice is either localize them or leave them out, which is what you do when you lower the LFE LPF.
You're not really leaving it out. The 'LPF of LFE' is not a brick-wall. You're rolling it off a little bit.
 
#10 ·
LOL ...yeah for sure! :p
 
#12 ·
I've tried everything in between 80-120hz and have pretty much settled on 90hz, also where I have all my crossovers set. To my ears it's a fair amount more cleaner sounding (some movies more than others). Other than when I used to sometimes bump my sub trims way to much trying to get more slam, I've never really thought my system ever sounded bloated/muddy/mushy or whatever you want to call it, even with still running my subs pretty hot, But oh man ...I think the bass definitely feels and sounds cleaner, tighter and punchier now, while at the same time being able to run my sub trims about 1db higher, which = more TR and Slam while sounding cleaner :) 1db might not sound like a lot, but it does help maximize TR and Slam while keeping that equilibrium just right and not sounding to bass heavy compared to the rest of the frequencies. Especially when your running the subs pretty hot.
^^^huh...who knew? I sure didn't! I always wondered why some would purposely want to filter/rolloff content that's on the disc...hmmm cleaner? punchier?, I'm going to have to give this a shot!

Thanks for making this thread... :cool:

Curious...do others feel the same way? Is that why you lower the LPF?
 
#13 ·
For awhile there I was running mine crossed at 90hz using line in. I went back to using the LFE channel a few months ago and will never go back. It was like my subs came back to life. I was missing out on so much mid-bass and I had no idea until I switched back.
 
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#15 ·
?????

Care to elaborate? What do you mean by "...........crossed at 90hz using line in"? What WERE you doing with the LFE channel? Did you configure your AVR/processor as having NO SUB?

?????
 
#21 ·
Like the title says ...LPF for LFE (for the .1 channel that is) and I'm loving it!!

I forget what thread I was reading a week or so ago in the bass section, but I came across a brief discussion of setting the LPF on the LFE channel at different Hz instead of the normal default of 120Hz.

IIRC, @Marc Alexander or @mthomas47 was saying they liked a 100hz setting, splitting the difference between 80 and 120hz.
You have a good memory! I think I mentioned this on the Nearfield MBM thread recently. It was fun reading about your experience, and it's been a while since I settled on my current compromise setting of 100Hz, so it may be time for me to reinvestigate the setting. My previous impressions have been that 80Hz is clearer sounding, but 120Hz has more oomph, so 100Hz was a compromise. But, I may be inspired to try 80Hz again.

The idea for this actually came from some discussions on the Audyssey thread several years ago, which ended up in the Audyssey FAQ, linked below. Roger Dressler (formerly of Dolby) and Mark Seaton pointed out some good reasons to use a lower LPF of LFE.

Regards,
Mike
 
#28 · (Edited)
I briefly messed with the LPF for LFE a few years back and ended up leaving it at default...I am definitely going to revisit this setting after your positive comments. Thanks!
I have found with messing with it for about a week on lots of different movie demo clips that the majority of the time (like maybe 95%), I prefer it at 90hz, sometimes even 100hz is not to bad, and maybe 80hz just a tad to lean sometimes. So I chose 90hz.

Like @audiofan1 was saying in his post, I have found that there are a few scenes that do sound and feel just a little better (more oomph maybe) with the LPF of LFE set to 110hz or 120hz and will kind of make you want to leave it there at the time. But then, for me, the majority of other great bass scenes, lower at 90hz just sounds better in my system: a little cleaner, leaner and punchier, revealing the multiple layers of bass and all the little nuances a little better that some of these amazing bass scenes have. But to compensate for it being a little bit leaner sounding going from 120hz to 90hz, I found that if I raise my sub trims by about 1db it pretty much made up for that while still sounding and feeling cleaner with more dynamics and punch if that makes sense. I could probably do the same for setting it to 80hz and raise trims a tad bit more and be real happy with it as well. But for what I've experienced so far, 90hz seems to be the sweet spot for me. So you guys that are gonna try this, be sure to try it at different Hz with several different clips.

If you go HERE Read through all of c)5. What is the LPF of LFE what should it be set to? Its a good read with some comments from Mark Seaton and a few others about it.
 
#26 ·
JT, what you missed the most with Rythmik line in connection (sub rolls off at 90hz) is the redirect bass from all of your speakers which was why it didn't sound as full. With your Rythmik LFE connection, you still can try to change the LPF to less than the default 120hz in your AVR (say 90hz), your sub(s) will still play all the redirect bass from speakers over 90hz if your speakers are crossovered at or above 90hz. I believe Mark Seaton mentioned that there is barely anything over 80 or 90hz in the .1 lfe channel.
 
#27 ·
I briefly messed with the LPF for LFE a few years back and ended up leaving it at default...I am definitely going to revisit this setting after your positive comments. Thanks!
 
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#29 ·
Hey @SBuger and others, just curious what receivers or pre-processors you're using. I've got a 10yr old Pioneer Elite and it seems pretty limited as far as bass management and crossover settings etc. Not shopping for anything new yet, just wondering which receivers feature these different settings and options you're discussing.
 
#32 ·
Mine is an Onkyo TX-NR5010. Was a flagship at one time (as I guess all are where at one point LOL), but not these days with ATMOS and all!. It's real comparable to the Denon 4520 that I compared it to for a while. I do love it for many reasons though, and it allows me to set a lot of different things to my liking, even with Audy engaged, whereas some wont.

Your post of bringing up the Pioneer has me thinking. I used to have one of the older Pioneer models before HDMI (I forget which model it was) and I also tried a couple different pioneer models at the same time I got my Onkyo.

One thing I noticed right away was the difference in bass between the Pioneer vs the Onkyo & Denon. The Onkyo and Denon were real similar IMO. Not that one was better than the other, but just a noticeable difference to me. This noticeable difference was mainly how fat and full sounding the bass was (I think these are the words I'm searching for to describe it). Or maybe a better term would be that the bass on the 3 different Pioneers compared to the Onkyo and Denon where that the bass just sounded and felt a little more damped on the Pioneers. Like I was saying though, I don't think that one is better than the other, just different and probably comes down to personal preference as to which one you may like better. Maybe the sound signature of the bass has changed a bit with some of the latest models, IDK. So what I'm trying to get at here is, maybe on the Pioneer, the lowering of the LPF of LFE may not be quite as noticeable/desirable since it's already naturally a bit leaner sounding (at least it was to my ears). Then again, maybe it would still be a worth while change for some folks. Any of you guys that are running the Pioneers messed with the LPF of LFE and found you like a lower setting than the default 120hz?
 
#30 ·
I have seen some receivers allow you to change LFE settings but on my Rotel 1068 prepro you can't even change the .1 LFE setting and its by default 120hz since all LFE is 120hz and below. The only bass crossover frequecy I can change is the bass crossover from the other speakers only. I currently have it set as 80hz where the subs get 80hz and below normally except the LFE signal gets 120hz and below all to the subs.
 
#34 · (Edited)
Sounds like you have room-mode issues OP.
By lowering the LPF you are probably just masking the modes above that frequency via attenuation.

Have you tried MBM's yet OP?

High-excursion subs are only good below 40hz.
High-efficiency MBM's are good for 50-200hz. Since they use 100db/w drivers they typically have a 10db advantage, which will give you huge chest-slam.

500watts from a PA-460 is equivalent to 3000watts from a SI-24 between 50-200hz. Something ridiculously like that anyway...

The SI-24 being $2000 and the 460 being
 
#35 · (Edited)
The short answer is:
Look at the chart, sorted by mid-bass! ;)



[Keep in mind the SI-24 was given 4-20kW here to make these sorts of numbers. But it did handle it. ;)]

It pretty much goes:
1) Horned PA drivers
2) PA Drivers / Horned high-excursion drivers
3) Elite high-excursion drivers ported or sealed
4) Everything else...

99% of music is 40hz and above. Top-100 Pop/dance/radio
Some rap, techno and dubstep may reach 30 to 20hz on occasion.
(Completely ignoring the handful of basshead-music like Bassotronics and Bass Mekanik which goes to 1-20hz on occasion.)
 

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#36 · (Edited)
Sorting the chart by upper infrasonics, we get these:


It pretty much goes:
1) Giant ULF horns featuring 1 or more 18's(or bigger)
2) Giant ported boxes featuring 1 or more 18's(or bigger)
3) Giant woofers in giant sealed boxes
4) Elite high-excursion drivers in various ported or sealed boxes, ranging from large to small.
5) Everything else...

14-20hz Horned having a 12-18db advantage here.
14-20hz Ported having a 8-12db advantage here.

For example: The LMS-18 being 104 sealed, and 118db horned. A 14db advantage.
The same could be said of nearly any other driver that goes from being put in a sealed box vs ported or horned.

If 115db-THX is considered to be "standard" for 1-20hz, as it is for >20hz,
then a lot of drivers are failing by this point.

Specially considering how inefficient our ears are at such frequencies, thus requiring even MORE spl to make up the difference...
 

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#45 ·
If 115db-THX is considered to be "standard" for 1-20hz, as it is for >20hz,
then a lot of drivers are failing by this point.
We scoff at the THX "standard" as it only covers response down to 25Hz.

Most of us don't listen at reference anyway. But running bass hot makes reference capability desirable. 20, 15, 10, and even 5Hz for some. Below 3Hz and definitely 1Hz is just not safe for most amplifiers and subs AFAIC. Josh Ricci at data-bass.com doesn't test below 10Hz AFAIK.
 
#38 ·
Mbm???
 
#40 · (Edited)
mid-bass module

i.e. a PA driver in some sort of box. Be it: sealed, ported or horned. Typically tuned 40-300hz and 95-105db/w.
Could be retail or DIY, such as:
Mackie Thump's, Behringer equivalents, JBL or JTR OS Pro's etc
or DIY B&C's, Beyma's, Eminence, BMS, Celestion or Dayton PA's etc
To name a few.

Some of the beefier mains like NotNyt's JBL's, 1899 or Fusion-15's maybe considered an "alternative route" to having dedicated MBM's. The problem is you can't just run mains "15db hot" like you can a dedicated MBM sub (not without ear-bleeding vocals as most mains are tuned flat from 20kHz on down.)

Without MBM's there is no guarantee you will have enough mid-bass to create the chest-slam you seek.
A rock concert will typically deploy 50-100 JTR OS Pro's or JBL evquivalents. With 2-4kW x 100.
Same for 100ftx100ftx50ft theaters (or bigger.)
They never use 10-20hz tuned subs in large rooms or open spaces, like ever... they are pretty much ALL low-excursion PA-drivers tuned to 40-50hz.

That's why concerts have face-melting sound. Lots of watts, Lots of horned subs, Tuned high.
 
#42 · (Edited)
lol I was wondering how long it would take before someone said I was using a lower than default setting of 120hz on the LPF of LFE to compensate for a setup/room mode issue. I go away for the weekend and check in right quick an Bam there it is ..Ha! :D

But true that could be part of it and probably could be better since my setup is in the middle of my untreated and less than ideal living room area, but still I don't think its to awful. I do the best I can with what I have to work with :)

@BassThatHz thanks for the education on the PA-460's. I try to keep an open mind and am always willing to learn and apply if I can when it comes to this HT bass stuff! :) I'm definitely aware of the PA460 and sure it kicks some serious butt for bringing on the mid bass chest slam! At the time I was building my SI DS4's I followed along with most of the discussions in the DIY section about the PA460. There were some members that absolutely love them for mid bass duties. I really enjoyed reading and learning about the experiences these folks had with the PA460 and definitely made me want to try one (or several)!

So that was one thing I was kind of concerned about when I went with the high excursion drivers and not being as efficient up in the mid bass area, that it may not deliver the kind of chest slam I like. But I was willing to give it a shot because I knew I definitely wanted them to be able to wobble the crap out of me with them parked right behind my seating with the drivers firing into my back/butt, which they do a damn good job of. So much so that they can make me feel pretty uneasy (which I love) on the ultra low stuff.

But fortunately I find that with 3 of the sealed DS4 18's NF behind me, they can deliver some pretty serious chest slam as well. Enough to be able to make me not feel so well with the amount of kick and pressure in the chest cavity that they can create in my fairly brief demo sessions, even at reasonable MV listening levels. I'm sure this pretty much is a direct result from the drivers being so close right behind me with the drivers firing into my back/butt area though. I guess I forgot to mention it in my first post, but I also do actually run a 1200D MBM stacked on top of one of the 18"s right behind the MLP which fires right into my upper back which helps as well. But even without the MBM running, these high excursion and lower midbass efficient drivers still hammer my chest and can feel heart beat altering on some material.

That being said, I can only imagine what a PA 460 or a stack of them right behind you could do!!! I'm thinking maybe making it hard to catch you breath and even hard on your heart, causing some type of damage if not careful :eek:

I have thought about ordering a PA460 driver at under a $100 and dropping it into one of my boxes that the DS4's are in just to check it out though like @bear123 did. Even if the 4cuft box might not be the optimum size for that driver. Maybe I'll try it one of these days and even build the right size box for it and put it where I now have the 1200D. I've thought about trying the magnum 12 as well. But the 1200 can do a pretty damn good job at delivering the chest slam if positioned and set up right. Maybe not as good as the PA460 or magnum 12, but still darn impressive and has the port tune around 50-55hz going for it! I'm sure you've read about @dominguez1 's subjective and objective tests that there is more TR around port tune. I've yet to see where anyone has done any subjective comparisons of these 3 for the amount of Midbass TR and chest slam that they can deliver with them being parked right behind you. Maybe I'll do it one if these days! Would be fun!

So anyway, I'm sure the mid bass doesn't hit me as hard as a system like yours or others like yours in dedicated rooms loaded with PA460's do, but it does put a huge smile on my face and a pretty good beating on me most of the time :)

But about my room possibly having some room mode issues - oh yeah no doubt with me having to be in the middle of my less than ideal untreated living room. I actually do have a few dips in that area around 110 to 130ish hz unfortunately. So yes this could be effecting why I prefer the LPF of LFE set to 90hz rather than 120hz. But I would think that a peak in this area would make me prefer a lower LPF setting to attenuate some of it like you mentioned.

IDK, but I definitely prefer it set a bit lower than the default of 120hz on the majority of demo clips, whatever the underlying reason may be.

That said though, I find it interesting that Mark Seaton, among a few others find that they like the LPF of LFE set down to around 80hz. (Not that we all have to like or share the same opinion on what he/they like, but there must be at least some truth and relevance to it right!?) Did you read his and a few others comments in the link I posted a couple posts back?

You didn't mention where you set yours at, but I take it you leave it set to 120hz? If so that's cool, I just wanted to hear what different folks set there's at and why.
 
#44 ·
Wow, this is a great thread. I had always assumed the BM crossover frequency was symmetric, meaning the BM XO frequency represented the high-pass cutoff for the mains/surrounds, and an equal value low-pass cutoff for the summed LFE channel. I was always puzzled why most AVRs had this extra setting. It seemed redundant unless for some reason you intentionally wanted to create a steeper LFE cutoff or notch around the BM XO by setting the LFE LPF at or lower than the BM XO.

I tried it last night by changing the LFE LPF on my MRX-720 from 120 Hz to 90 Hz and listened to a couple of familiar mid-bass heavy music videos. It really seemed to make a nice difference in mid-bass definition and impact.
 
#47 · (Edited)
The crossover for the main channel's (F, L, C, and surrounds) bass management IS symmetric. The high-pass and low-pass filters are at the same value that you set in the AVR. What is not symmetric about the crossover is the slopes of the filters. In most AVRs the high-pass filter is 12dB/octave and the low-pass filter is 24dB/octave.

But the 'LPF of LFE' setting is NOT redundant. The 'LPF of LFE' filter is ONLY applied to the LFE channel (the .1 channel) info and not to the other bass managed bass from the other channels. So, you could have a 80Hz crossover set for your main channels, which would low-pass that bass at 80Hz, but have the LFE channel being low-passed at 120Hz by the 'LPF of LFE'. Or, likewise, you could have a 120Hz crossover set for your main channels, which would low-pass that bass at 120Hz, but have the LFE channel being low-passed at 80Hz by the 'LPF of LFE'.

The two filters (the low-pass filter of your crossover setting and the 'LPF of LFE') are completely independent of one another. One is applied to your main channels' bass ONLY. The other is applied to the LFE channel ONLY. The low-passed main channel bass is summed with the low-passed LFE channel bass after both of those filters are applied, digitally, in the AVR. The 'LPF of LFE' setting does not affect the bass-managed bass's filter value. And vice versa.

With 2-channel music, the 'LPF of LFE' setting will not make any difference at all as there is no LFE channel present in 2-channel source material.
 
#49 ·
I'm a little confused.. where is this setting? Where in the AVR do you find it? I have a Pioneer Elite VSX-90 7.2 and from what I've learned is Pioneer doesn't have separate crossover settings. It has one overall crossover setting and mine is at 100hz.
 

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#53 ·
Thanks for the suggestion. Actually I don't have my FV15HP in the mix with that option ATM. I have messed with that though in the past and always seemed to prefer the LFE input. So you use the Line In input on your FV and like the results? If so, cool! :)
 
#54 ·
I don't use line input. It's just that if one's using a sub near-field and they have peaky 80-120Hz region, they may use line input to filter LFE content above 80hz to avoid localisation.
 
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