What to set the low pass at for KSW200 Sub?

[George2002]

Hello, I need some help with setting the Low-pass dial on the back of the KSW-200 subwoofer.Ok the amp I'm using is a Onkyo TX-SV 545 it's a digital ready recever and does not have any bass management other then *sub-yes,no* and I belive on it's sub out it's set at a fixed 80hz. I using the sub out from the reciver to the sub in on the subwoofer. This sub has no life input* My main speakers are large floor models so they can handle base down to 40hz. Do I set the low pass dial to full 120hz with this setup or say 45hz or so? I use this system for 95% music 5%DVD video.

Also I did do the put sub where you sit thing to find the best spot and do have a rat Shack SLP meter.I had this sub and setup for about two years and was not happy with the bass output or blend of the sub sound for music but always ran the sub low pass dial from 40hz to 80hz...power level on the sub at 6 or 7 and if I turned it up the music would sound muddy. I never felt any kick or shake with music.I think you all should know where I'm coming from with this setup info any help would be appreciated! Thanks! George

[Stu Pidass]

George:

Others may be more qualified to answer your question(s) but I'll give you my 2 cents, for what it's worth. Your receiver may lack control over bass management (most do at least to some degree). I believe the reason why HT generally uses the 80hz crossover is linked to THX certification. That being a sattellite speaker system utilizing a sub for the low end. With full range speakers this doesn't really fit your setup. I had the same damn problem as have others on this board.

The LFE signal (not "LIFE") is built into movie tracks and stands for "Low Frequency Effects". It's the receiver that sends this "extra" signal to the subwoofer through the subout cable. Therefore the sub does not require any kind of "LFE in", it simply receives the signal from the receiver and responds accordingly. The following quote from another sourse may help explain the LFE stuff:

"Just because THX specified a suggested LFE cutoff frequency, doesn't mean it is correct or that it must be followed. It seems that everyone is forgetting what a subwoofer is meant to do. It is meant to act like a subwoofer, not a woofer. The purpose of a subwoofer is to reproduce very low frequencies that most loudspeakers cannot reproduce with authority on their own. In the 5.1 Digital realm, the LFE channel was introduced as a means to alleviate the demand placed on the other channels to deliver low frequencies with ample amounts of "oomph" without limiting the dynamic range. The majority of Receiver Companies continuously produce Receivers with a fixed LFE cutoff (-3dB) at 80-90Hz. These frequencies are high enough to still sound directional, especially if the sub is located in close proximity to the listening position. This makes it easy to locate the sub in the listening room and / or reinforcing standing bass waves in the listening room (60Hz) by coupling with the bass output from the main speakers if they are configured large.

if you are using quality "large" Tower type speakers with inherently good bass extension. You will find the addition of a sub is much more useful as a compliment to your main speakers, producing deep, non-directional bass tones.

Alternatively, you can give into the industry and accept the fact that most Receivers set their LFE at one frequency (fc = 90Hz), high enough to be allow your sub to play up to almost a 100Hz, which will most likely constructively interfering with your main speakers, increasing the chances of:

1) Unwanted and unnatural sounding standing bass waves,

2) Identifying the subwoofer as a point source rather than a discrete member.

3) Excessive bass boom. "f>"

OK, so I also have a PW2200 with full range mains and use it for both 2 channel audio & HT. Here was my solution. I hooked the sub up with both the Sub Out cable and also with speaker cables that share the main speakers sourse. In the sub is hooked up using the speaker main outs on the back of the receiver. This way during 2 channel audio I can use the sub to compliment my mains. This is achieved by setting the crossover adjustment to 45 -50 hz. My speakers do very well down to 40-45 hz and then start to roll off. That's where the sub comes in. It does not overpower them but simply blends and fills in the deep non directional bass. To set the ssytem up adjust the volume of the sub to the correct level. Not overpowering but simply blending with your mains. Then use the receiver setup to adjust the volume of your sub with the help of a rat shack SPL. No adjustments are required when switching between movies and 2 channel audio. It works GREAT!

At the risk of overextending this post I am pasting more info regarding the subject from another sourse as follows (it's great info):

"Lately I have been receiving numerous emails from fellow Audioholics regarding subwoofer operation problems with their DD/DTS AVR Receivers. One of the most common scenarios is where the user has a 5.1 speaker system, but the AVR Receiver does not allow subwoofer output in 2-channel. Another is when the user has large bass capable main speakers but they experience no bass output, in 2-channel mode, to the subwoofer if the main speakers are configured large.

The Solution:

For the 1st scenario, no subwoofer output in 2 channel, regardless of speaker settings, I recommend the following if you have bass capable main, center and rear speakers:

Set all speakers to "large". This bypasses all of the High Pass Filters (HPF) built into the receiver. Usually these Receivers with poor bass management set the cut off frequency too high (between 80-100Hz) with a gradual roll off of 6-12dB/octave and thus they are not worth using in my opinion.

Set the subwoofer setting to "none".

If the Receiver has preamp outputs for the main channels, then connect the left and right main preamp outputs of the Receiver to the inputs of the subwoofer, just like you would hook up any other component such as a DVD or CD player.

Note: Make sure you connect both left and right channels into the sub, otherwise you will loose significant bass information and amplitude being sent to the subwoofer. This will ensure all of the left and right channel bass information is being routed to the subwoofer.

If you do not have preamp outputs on the main channels, you must connect the subwoofer via speaker level to the main speakers.

Note: Make sure when you connect the sub to the main channel speaker level that the connection is in parallel. If you use the speaker "B" outputs to connect your sub, press it 1st to verify that the connection is in parallel. If you can still hear sound out of the mains, then the connection is in parallel. If not, than you will have to connect the sub and the mains through speaker "A".

Adjust the subwoofer cross-over setting between 50-60Hz.

Adjust master volume of Receiver to a typical listening level.

Adjust subwoofer volume on subwoofer to a level that sounds appropriate.

For the 2nd scenario where you have bass capable main speakers, but small, bass shy center and rear speakers, repeat the above steps with the following exceptions:

Set the center and rear speakers to "small"

Adjust the subwoofer cross-over to around 80-90Hz. This will ensure optimal blend with the internal HPF's cut-off frequencies for the center and rear channels of the Receiver."

Good luck and enjoy the show.

Regards,

Stu

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'81 Cornwall 1 mains B2 Crossover

'73 Heresy Centre

'78 Heresy Surrounds

Paradigm PW220 Sub Subwoofer (18 hz)

Marantz SR8000 AV Receiver

Hitachi 53" RPTV 53SBX59B

[Stu Pidass]

George:

Sorry to possibly add to your confusion but I have more info relevant to your problem (again quoted from another sourse). See the following:

"The Marriage between the Subwoofer and Tower Speakers

Some marriages are easier than others. They require minimal maintenance to flourish and thrive successfully on mutual cooperation right off the bat. Some marriages however, are not so divine and can be bitter sweet at times of chaos requiring much nurturing to prevent rotten out. Such is the case with home theater. When one chooses the commitment of buying bass capable tower speakers and mating them with a subwoofer for home theater and music applications, the potential of sonic bliss or troubled misfortunes begin brewing. The purpose of this article is to identify and red flag issues which may lead to problems when combining a subwoofer with bass capable speakers.

1.0 Fixed LFE output of 80-90Hz.

Most Receivers and Processors have one fixed LFE setting of about 80-90Hz as per THX recommendation. Please review the article I wrote "Turn That LFE Setting Down". for more ellaboration on this topic.

In my opinion, Lucas should stick to creating puppets for Star Wars and stop trying to concoct useless or unwarranted specifications for Surround Sound. Bass waves are localizable to the human ear as far down as 60Hz and thus crossing over a subwoofer at 80-90Hz may lead to overemphasis of these frequencies resulting in unnatural, colored and localizable bass. In addition, a high crossover setting for a subwoofer buttressed with bass capable speakers only amplifies this problem because of their synergistic effect.

2.0 Non-defeatable crossover on sub or processor or both.

To combat problem flagged in #1, it would be useful to defeat the LPF (Low Pass Filter) internal to the Receiver/Processor. If this is not possible, the user may have no choice but to use the adjustable LPF of the subwoofer in conjunction with the LPF from the Receiver/Processor.

Doing so may result in problems with:

Too much transition band attenuation, excessively attenuated signal.

Added group delay of 2 filters cascaded causing phasing problems between subwoofer and main speakers. The result is unwanted canceling of certain bass frequencies.

Null or resonance caused by impedance change resulting in accentuation or attenuation of particular frequencies within the passband of the subwoofer.

3.0 Minimal group delay of digital LPF in processor.

Let us simplistically define group delay as the rate of change of the total phase shift with respect to angular frequency. Most high end Receivers/Processors handle bass management in the digital domain and thus all of the filtering is done digitally. Digital FIR filtering is very good, sometimes too good in that these filters add no group delay. Ideally this is desirable, until you couple this system with a pair of bass capable speakers that have a woofer crossed over with an analog filter. The added group delay from the analog filter within the speakers can cause a phasing problem with the subwoofer resulting in poor bass response (see point #2 above). There are two potential ways to combat this dilemma:

Reverse or adjust the phase of the subwoofer via the phase control on the back panel.

Reduce the distance of the subwoofer relative to the listening position in the set-up of the Processor if that feature is contained within (IE. The shorter the physical distance you enter into the processor between the sub and listening position, the more delay the processor adds to the sub output).

4.0 Phase switch on subwoofer.

A phase switch basically electrically reverses the polarity of the subwoofer and thus changes phase angle by 180 degrees. This is sometimes useful in cases where the Receiver/Processor subwoofer output is electrically out of phase with the speaker outputs. Use this option with caution, starting with the 0 degree as default. Let your ear be the judge as to which position allows your subwoofer and speakers to perform optimally. Usually there is a drastic and obvious difference between both settings. If you hear no difference, then I recommend keeping the switch set at 0 degrees.

5.0 Placement issues of subwoofer and/or speakers.

Perhaps the most critical parameter to ensure optimal performance between your subwoofer and speakers is placement.

I recommend reading the article I wrote regarding speaker placement at:

http://audioholics.com/tip2.htm

and the article I wrote regarding subwoofer placement at:

http://audioholics.com/tip1.htm

as starting points, and experiment liberally on your own. As a rule of thumb, bass amplitude reaches its maximum potential if the subwoofer is placed in the corner of a room where in has many surfaces to couple with. This does not imply however you will achieve optimal bass performance with respect to accuracy or finesse. Experimentation is a golden rule!

6.0 Tuning Frequency relationship between subwoofer and speakers.

Speakers, particularly woofers, are designed to work within a calculated volume to achieve optimal performance. Bass Reflex speakers/subwoofers use a port or opening to tune the cabinet to a certain frequency to ensure optimal frequency response and dampening characteristics for the system. It is desirable for the speakers and subwoofer to be tuned to the same frequency for optimal blend and uniform bass response of the system as a whole. This helps to maintain proper mechanical phase between the subwoofer and speakers resulting in a seemliness blend between the two. This point is mostly important when matching large bass capable speakers with a subwoofer, and becomes a moot point when blending a pair of small, bass deficient speakers with a subwoofer.

Conclusion

The statements above regarding subwoofer and speaker blending were listed as potential issues one may come across when setting up such a system. It was the intent of this article to tactically assist the consumer in combating these common issues. There are many rewards in combining a subwoofer with bass capable speakers for home theater and home audio applications. I believe the ultimate way to ensure perfect blend and reproduction of all frequencies within human hearing limitations, may be achieved with this type of set-up if executed properly. It is sometimes an arduous task for neophytes and even the Audioholics to achieve perfection in their system. It requires time, patience, cooperation, understanding, and care to achieve this feat, not dissimilar to a healthy and prosperous marriage. Good luck and keep listening!"

Regards,

Stu

f>

------------------

'81 Cornwall 1 mains B2 Crossover

'73 Heresy Centre

'78 Heresy Surrounds

Paradigm PW220 Sub Subwoofer (18 hz)

Marantz SR8000 AV Receiver

Hitachi 53" RPTV 53SBX59B

[George2002]

Stu Pidass, Wow thank you for all the great info! To tell you the truth I'm a little overwhelmed with all the info. I'm taking it in in slow. Also checked out the url links you sent. Great read and had a look around on that site great place to learn. I'm going to make some changes to our system and see how it sounds. I know I'll have some more questions for you if it's ok with you I'll post them on this board as

*ATT Stu Pidass*. I think the thing I realy need to start is that Y adapter to get the 6 db gain. I'm still running from sub out on the receiver to the sub in on the sub I know my receiver uses a 80hz filter. My main speakers go down well to 45 to 50 hz so I set the sub low pass dial to 50kz. Think after doing a little reaing I'll change to the Y and the line in on the sub for the 6db gain. I'll see how that sounds. If I have to I may go and hook up things to speaker level from the receiver to the high level input on the sub.Not sure, what do you think? Hey thanks again for all the great info! George

[Stu Pidass]

George:

My Knowledge on the subject started on this board and is limited to my own particular receiver/sub combination. I'll be happy to help in any way I can, however, I'm not a guru on the subject. To be honest this is one of the most complex steps in any setero setup. It's almost overwelming at first. Try some searches on the subject and check out this short cut to my first question.

http://216.37.9.58/ubb/Forum8/HTML/000706.html

Boa12 helped me a lot initially and is a very good source. The info posted above and related links are the best, most concise and complete information I've run across.

Good luck & have fun.

Regards,

Stuf>

------------------

'81 Cornwall 1 mains B2 Crossover

'73 Heresy Centre

'78 Heresy Surrounds

Paradigm PW220 Sub Subwoofer

Marantz SR8000 AV Receiver

Hitachi 53" RPTV 53SBX59B