LFE Setting for KSW12

[bacevedo]

I just wanted to post a question to the brain trust here.

I have a KSW12, and Denon 3801 with the sub hooked up from the sub pre-out on the receiver (Y adapter to L&R on the sub). When I use my AVIA DVD to set the level of the sub, it sounds great. But when I listen to music, the sub isn't loud enough (at least to me). So I end up turning it up. But then on movies, the sub may distort on some loud bass sequence.

Here is what I think is happening, and what I did. I know that the LFE channel can be up to 10 db higher, so that you can get 115 db from that channel. But I read that there is practically no consumer sub that can produce that kind of level (at least not in my price range). So, it is totally unrealistic for me to set my sub up to try and reproduce those levels. But if I use the AVIA DVD calibration, I am setting the sub up to do just that, or am I? Is the signal on the AVIA DVD recorded 10db higher, or is it recorded at the same level as the other test tones?

What I did instead, was to adjust my sub to how I like it on music. Then, I adjusted the LFE on my receiver (you can only get to it when in Dolby Digital or DTS mode) down about 5db. You can cut from 0 - 10 db, but it doesn't effect the actual sub output, so music and the other channel levels are not effected. I realized they have this so that when they try to hit 115 db on an explosion, I can cut back 10db so that it is 105 db - something this sub can probably handle. So my setting would allow 110 db - will this sub handle that?

Can anyone enlighten me about all of these assumptions and questions and just give some general knowledge about LFE settings.

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Thanks,

Bryan

[boa12]

which mains do u have? u may want to tinker w/ your bass mgmt. settings, like fronts small & output sub only f.e.

here's a good lfe doc:

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Klipsch KLF-30 (front), KLF-C7, Cornwall I (rear)

Velodyne HGS-18 sub woofer

Monsterbass 400 sub interconnect & Monster S-12 cable

Sony STR-DE935 a/v receiver

Sony DVP-C650D cd/dvd player

Sony Trinitron 27" stereo tv

Toshiba hi-fi stereo vcr

Technics dual cassette deck

Technics direct drive turntable

Scientific Atlanta Explorer 2000 digital cable box

2nd room:

Klipsch RF-3 (front), RC-3, cheap little Technics (rear)

Kenwood KR-9600 AM/FM stereo receiver (vintage '75)

Teac PD-D1200 5-disk cd player

Sega Genesis game player

Sub: None yet

rock on!

[Domain]

bacvaedo,

Well, you've saved me the trouble of posting something very similiar

My setup is very similiar to your own (Denon 2801 / KSW-12 / Sub Out + Y Adapter). I find myself changing the level on the sub 10+ times a day, never finding a middle ground between music / HT.

Now, i'm new to all of this (but working very hard to learn), so I could be (and most likely am) wrong, but I think the first problem lies with the Denon's Sub Out (at least in my case). I've calibrated the Denon's channel level (all to 75 db) with a SPL meter, and this seems to be good for HT application, but for music is seems useless. (In my room, the calibration produces the following results: Denon's Sub channel level @ 0db, Sub level at 9 o'clock).

I listen at fairly low volume levels (-30 to -25 on the Denon volume level), and these settings prove good for HT (plenty of low end punch), but in music the sub doesn't even "wake up" at these volume levels. Upping the volume on the Denon to around -20 will activate the sub, but even then, its not audible (I have to crank the Sub's level to 12 o'clock to have nice, blending bass).

Now, it would seem logical to just to leave the level on the Sub's at 9 o'clock, and up the Denon's Sub level, but this does absolutely nothing on my unit (no audible difference from 0db to +8db). The only way to get decent bass (without changing the Sub's level) its to crank the volume level on the Denon, which seems to double the bass output every +10 on the volume level (but makes it somewhat uncomfortable for casual listening). So, I'm beggining to think that the Sub Out isn't a good way to hook up the Sub, and after I finish moving, I suspect I'm going to try Speaker level....

Now as far as LFE is concerned, from what I've read, the "standard" provides for a 115db output on the sub at "reference" volume levels. However, the same sources also explain that this is not pratical for a HT application, since (at least lower end) consumer level equipment won't be able to produce these levels properly. I would also think that a "reference" volume level in a HT application wouldn't be very comfortable (105 db for the mains would be painful, and easily damaging to hearing).

I would assume that calibrating the sub for +10db for LFE would not be an issue, as long as you didn't try to reach these "reference" levels, since it will never actually reach 115db output (but still get +10db over the other channels).

Finally as far as Avia is concerned, I've been told that it is NOT recorded at +10db on the LFE (but Video essentials IS). I can't verify this, since I haven't purchased Avia yet (but plan to in the near future).

There are a lot of links to LFE information (like BOA posted), and I read a really good one the other day, but I can't find it at the moment, so when I do i'll post it here.

Domain

Heres a link HornEd posted on the HT forum regarding LFE

http://www.hometheaterhifi.com/volume_7_2/feature-article-misunderstood-lfe-channel-april-2000.html

[bacevedo]

Thanks guys, I found another good article as well.

http://www.hometheaterhifi.com/volume_7_2/feature-article-misunderstood-lfe-channel-april-2000.html

One other thing that I did was to move the sub, and this cleaned up the bass quite a bit. It didn't sound "compressed" (like it was trying to move more air then it could, or like you were holding your hand over the port) when I moved it to my side wall and out into the room more. The entire room is filled with bass now - not many nulls anymore! I don't think it had enough room to "breathe" and move the air in the old spot.

Boa - I have RB5's as my mains, and right now they are set to small. I played with large and small, and I found that the bass just became boomy when they were large - the sub and the bookshelfs were creating a peak at their overlapping frequencies. Setting to small, cleared up the highs (as expected), and created a nice smooth sound.

Domain - I have calibrated as well with an SPL meter - to 85 db. But I did it differently then most people might do with a Denon receiver. Most people turn it to 0 (ref level) and then adjust from there. Well, since Klipsch speakers are so efficient, most people have to trim back their settings quite a bit. I just sent the tone through the left speaker and turned the volume up until I hit 85 db. I noted this volume setting, in case I want to play at this level in the future (which I don't because it is so damn loud). Next, I calibrated all of the speakers to this level. I did it this way because I didn't want to waste the sensitivity of these Klipsch speakers. What good is it to have 96db if you just trim back your level to -6db? You are making your amp work harder then it needs to. After doing this, I realized my center channel (RC3) had the highest sensitivity. So I readjusted everything by another +1 db - so that my center channel was set to 0 (instead of -1), my fronts are at +1, and my rears (RCW3) are at about +4. I don't like doing a minus setting on the speakers, because you are just "wasting" their sensitivity (at least in my opinion).

Then I adjusted the sub, but I found that I am adjusting it too low for my tastes. I think it has more to do with not using the SPL meter correctly on the sub, as it is harder to set the correct level (the needle seems to jump more in my setup on the sub setup). Also, I never use the level setting on the receiver for the sub out (it is always at 0). All that you will do is possibly overdrive the input on the sub (and possibly blow a fuse) or add distortion because you are overdriving the denon sub out.

I haven't readjusted since I moved the sub, so I need to do that. I will report my findings back here after I have a chance to do it.

I know what you mean about the volume control increasing the sub out. I wonder if the volume control is not linear (or maybe it is linear, and most aren't). Because the bass doesn't totally increase the same as the other speakers do when the volume is adjusted. I think it has more to do with the Klipsch speakers being more efficient than the subs. I think the weakest link in my entire system is the sub itself (it is afterall a synergy series - not a reference series speaker). But I like all of my components to be from the same company, so I got it anyway. The new reference series subs will probably be killer and match better - but there is no way my wife will let me spend the extra money to get one!

Bryan

[boa12]

have u guys considered just connecting the ksw in your main preouts/powerins (if available) loop. then set sub:no & just use the sub crossover for bass mgmt?

there are some other funky hook-ups posted for the ksw - like using B speaker levels, etc.

[Domain]

bacevedo,

The way you callibrated your system is very interesting, and very helpful information. When I adjusted the levels on my system, I had to adjust many of the levels WAY down (-7 db on the mains, -3 on the center, 0db on the surrounds). Last night I spent about 3 hours playing around with the system (mainly on the bass), but I did notice that especially on the mains, as the Denon's channel level decreases, the horns become extremely "muddy/washed out". I found it very apparent when I switch from Direct or Stereo, to 5 Channel Stereo, the mains had a completely different sound from the center (the center was very clear vs the muddy/washed out mains).

As far as the Denon's Sub level, I leave mine set at 0db, though as I said I upped it to +8, with no audible difference, so it seems to be useless anyway. I find the Denon's bass management strange to say the least...and horribly confusing. The overlapping filters probably don't help the situation either...

I've read that people get drastic results from going the Speaker Level route, and I'm thinking I might get a better "blend" by utilizing the sub's high pass filter anyway.

Of course, I am most definately, probably wrong

Boa,

Errr....I might be confused here, so forgive me. I'm pretty sure the Sub Out, is part of the Pre-Out section, though if the Sub is turned Off, it turns off the Sub Out...(this may be different for his 3801 as I have a 2801).

2801 Specs:

http://elec.denon.co.jp/europe/pdf/AVR2801.pdf

3801 Specs:

http://elec.denon.co.jp/europe/pdf/AVR3801.pdf

Domain

[boa12]

domain, right u could hook up the ksw to the main preouts & NOT the sub preout jack(s).

[Domain]

Boa,

Sorry, I see what your talking about now. I feel stupid

Domain

[bacevedo]

I thought about doing that - hooking the sub L & R to my receiver L & R preouts. Then I would have to turn sub to No, and front speakers to large. Since I wouldn't have any crossover on my mains (RB5), they would be getting all bass and LFE info. They can't play that deep, and I think it would really bring down the sound quality of the mids and highs because the Denon would now not only have to amplify L & R bass, but LFE, center and rears as well. I could do the speaker levels inputs, but again, this will make the receiver work harder then it needs to, only to have the bass filtered out by the sub. I also have a problem with using high level inputs (I don't know why - just bothers me), because you are adding one more processing step - dropping the signal back down for the sub - and using the sub to crossover after the fact. I think the digital bass mgmt of the Denon is superior to any crossover in a sub.

I think I solved my problem by repoistioning the sub. Now the LFE doesn't sound distorted, and my music has a nice tight, punchy bass. It sounds pretty impressive on movies - the whole couch (a huge sectional) shakes! I think that the KSW 12 is very dependent on the room acoustics, and not having it placed correctly can have drastic results. I know in my case it did.

Domain - what other speakers are you using? I know that my mains sounded muddy - and after repositioning them, they sound a lot better. I had mine on top of my TV (way too high) and now they are on the floor, waiting for speaker stands. They actually sound better on the floor - and they are bookshelfs! Once I get the stands (having some made) I can't wait to hear the difference. I know that the horns in my speakers need to be about ear height, since mine were above ear height even when I was standing up, I was missing a lot of sound. Try adjusting your system like I did - so you don't make the amp work harder. You are basically setting it so that you have to turn your volume up 7db higher - more than 4 times the power will be needed - to get the same sound as if they were at 0. Changing your center to +4, and your mains to 0, and whatever your surrounds need to be (maybe +7), should help you out. You will not need to turn the volume up as high (but that is a good thing) to get the same sound level. That is what I mean by "wasting" the sensitivity of the speakers. You should get better headroom and dynamic range this way as well. Or am I missing something here? Does it matter how you do this?

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Thanks,

Bryan

[bacevedo]

Let me clarify why I am asking if I am missing something on the level settings.

Is there any difference between setting my receiver volume to 0, and then trimming the level of the channel to -7 as opposed to leaving my channel level at 0 and setting the receiver volume to -7? The sound output is the same, but is my receiver using more or less power between the two. What if I set the level to + 7 and leave my volume on my receiver at -14?

I think what I should be saying is that you are allowing your receiver some extra room to spare in case you want to play above reference levels. In the case of leaving the channel level at 0, I can turn my volume up another 7db, as opposed to maxing out with the channel level at -7. I think my receiver goes to +18 on the volume. But if you set any channels in the + range on their level, the + 18 changes accordingly (i.e. it is + 14 because my surrounds are set at +4). I have never taken my receiver above 0 - and probably never will - it is already very loud.

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Thanks,

Bryan

[boa12]

dac, the way around that is u then run lines from the ksw line OUTS to the power INS of your denon thus completing the loop & then being able to control the freq level to your

rb w/ the ksw crossover. clear as mud?

[Domain]

bacevedo,

The other speakers are in the Synergy (SF-1, SC-1, SS-1).

I'm definately going to play around with the level adjustments as you mentioned, I expect I will have much better results.

However, I see a problem as the rest of the speakers become more "sensitive" and less volume being required. Seeing that the sub barely activates as is until -20 or so on the Denon, it may not activate at all when those adjustments are made, since the volume level will be much lower...

I'm just curious though, since i'm not very knowledgeable on this, would adding +dbs on the channel levels for the speakers be detrimental to the speakers as it is for the sub? Is this not the case because the sub has its own amplifier?

Domain <--- Is a sponge for knowledge

I've also played musical speakers all last weekend, and found basically where I feel they sound the best. It was a interesting experience though, I was listening after calibration...thinking....wow this sounds good. Then I looked over, and the sub was "asleep". Bah...

Oh well, gives me something to do, even if I end up pulling all my hair out

Domain

Boa,

The KSW-12 unfortunately doesn't have Line outs, just speaker level outs...

[boa12]

dom, whoops that's significant

guess the ksw-10 has no outs. well I guess you could do above speaker level, but u probably like the sound better using line interconnects.

may want to do both, line & speaker level then. connect the mains to the ksw speaker outs. take care of that music crossover prob.

[bacevedo]

Boa - how does that work? Don't I then have to select my 8 Ch input to get the signal to my mains? How can I select different audio sources if I have to select the direct channel inputs?

Domain - good point about the level matching with the sub. In my case it works fine, because I leave my sub on 24/7.

I asked my dealer, and he said the entire staff leaves their subs on all of the time. It is not bad for them, and draws almost no current when not being played. My electric bill didn't go up, so I don't worry about it. Now I always have bass, no matter what the volume, and never have the sub turn off in the middle of a movie.

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Thanks,

Bryan

[boa12]

w/ the ksw-12 i've heard many do both.

that is run interconnect from the sub preout to both ksw line inputs then run your speaker wire from the front speaker outs to the ksw speaker ins & then from the ksw speaker outs to the main speakers. then u can use the sub crossover control for your mains, but u still have the receiver bass mgmt working from the sub out (sub:yes) jack to the sub via the line connections. try it u may like it. just takes some cheap speaker cable & a few mins.

[Domain]

bacevedo,

Its a interesting situation. I don't have problem with leaving the sub at "on" all the time, but when its on auto, it only turns on when I recieves a signal (or perhaps when it recieves a powerful enough signal?)

So until the reciever is reaching a certain volume level, appartenly it is not producing a signal, or a powerful enough signal to even activate the subwoofer. So when this is occuring, the sub is just sitting the corner looking pretty, but not doing anything (wheter its set to on or auto).

I'm not sure the Sub Out is on the same "level" with the speaker outs if you know what I mean... but then again I could be wrong.

Boa,

I've heard about people running dual connections (speaker and line level) to the sub, but i'm not sure if this is safe? The sub's documentation says you can use one, or the other, but not both.

Domain

[boa12]

dom, i think the manual is just saying u can't just run lines into the ksw & just speaker levels out of it to the mains (then u get no output to the mains by speaker outs).

because the ksw does not internally sum the inputs, i see no safety problem. many are doing it w/ no probs.

[Domain]

Boa,

I might try that as soon as I get moved (oh boy, new room, new acoustics, another 12 hours of playing musical speakers ).

I'm curious though, if your running both Line/Speaker level, then your sending a unfiltered signal to the KSW-12 from the speaker level, and a filtered signal from the Sub Out.

Now, you said the input signals are not "summed", and while your sending the same single to both inputs, the filters aren't going to matched...(I may be going over my own head with this next one)...since the filters aren't at the same frequency, wouldn't they slope differently?...and how would the sub reproduce this?

<scratches head>

Maybe i'm reading too much lately... the confusion is setting in...

Domain

I can't spell

[t-man]

gentlemen,

B4 connecting as Boa is currently suggesting you try...consider my post (see Denon and KSW-12 FYI). I have tried ALL of the above recommended setups, and have settled on using speaker level in/out only.

When I first tried using both speaker level and line level, I noticed an immediate boost in volume. However, this may not be safe. I think it IS SUMMED. You cannot turn the volume on the sub past 12-1 oclock without the amp squealing like a pig. It doesn't matter if the denon is set to "sub no" or "sub yes".

With speaker level, need to crank volume lever up a bit, but no squeal (I feel safer this way). With enough volume tweaking, I don't think it sounds any worse or has less bass than having both hooked up. I don't really see the advantage to using both connections. Afterall, it says explicitly in the manual NOT to do this. There must be a reason...

I also feel comfortable using just one crossover (sub's in my case) as opposed to 2 (using denon's sub out). Once again, less variables to consider...makes me feel like I'm not missing some sound.

An yes, it definitely makes a difference where you place the sub. Night and day in my case. Needs to be in corner behind mains for me. On side wall, it just sucked.

Best of luck,

T-man

[boa12]

hey, like i said, i was just echoing what many have said to do. i'd sure like to see the schematics on those ksw. guess they're a big secret.

the line inputs are not internally summed. that's for sure - otherwise why would u get such a boost in output just by hooking up both line inputs?

as much as klipsch claims their powered speakers have all these many connection features, i'm sorry but their ksw subs are a poor representation of that claim. the only way to really ensure the best compatiability for all the dif receivers out there in all formats & for folks who prefer the sound of line connects over speaker level would be of course to put line level outputs on these subs.

as t-bird found, w/ these subs the only way to really find out is trial & error, which makes his experience moot to different cases.

so let the mayhem continue- i'll leave it to the people who own 1 or care anymore