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    Senior Member pathfindermwd's Avatar
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    Hardwood Flooring Acoustic Help

    I'm having real difficulties getting my L100S's to perform well at my girlfriends place. Her living room is large with laminate hardwood flooring. There is is a real lack of bass, and an abundance of mid-range, which seems very scattered. Turning down the L-pads seems to have little effect to clean up the sound. I know that hardwood flooring can cause alot of reflections, and that an area rug would really help.
    You can see that I have picked up the speakers with boxes, this has helped the reflections a little. I wonder if the lack of bass has to do with the length of the wall behind the speakers, providing little boundary reinforcement, as compared to how my set up is at home, or do the high ceilings also play a role? The room is much larger than my living room at home, and I almost wonder if the speakers are simply too small for this room. I attach a few pics so that you can get a better idea of the layout. If I did not know what these speakers were capable of, I would think that they were completely incompetent, but I know that is not the case. What effort can I make that would do the most good?

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  2. #2
    Moderator hjames's Avatar
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    I've had L100T and L100t3s - no lack of bass with either of those, even with just 60-75w/ch receivers

    What kind of power are you running them with - how many watts?

    Looks like a ground level floor -is it possible the hardwood floor is against a cement slab -
    maybe it was installed with some kind of foam absorption layer that's damping the bass ...
    (like they do with Pergo &r some of the similar composite wood floor materials)?

    Put a small piece (maybe 10 x 14 or so) of MDF flat on the floor, then use a set of speaker spikes
    to give the speakers a more stable footing ...
    That's a pretty cheap test to see if you get an improvement.

    You could also try a small throw rug to see what effect that has ...

    Cardboard boxes are no good - you need something SOLID -
    you could make a wooden box/pedestal if you think the height is helping ...

    Quote Originally Posted by pathfindermwd View Post
    I'm having real difficulties getting my L100S's to perform well at my girlfriends place. Her living room is large with laminate hardwood flooring.
    There is is a real lack of bass, and an abundance of mid-range, which seems very scattered. Turning down the L-pads seems to have little effect
    to clean up the sound. I know that hardwood flooring can cause alot of reflections, and that an area rug would really help.
    You can see that I have picked up the speakers with boxes, this has helped the reflections a little.
    2ch: WiiM Pro; Topping E30 II DAC; Oppo, Acurus RL-11, Acurus A200, JBL Dynamics Project - Offline: L212-TwinStack, VonSchweikert VR-4
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    Senior Member pathfindermwd's Avatar
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    Quote Originally Posted by hjames View Post
    What kind of power are you running them with? How many watts?
    Is it possible the hardwood floor is over a cement base -
    maybe setting on some kind of foam absorption layer thats damping the bass ...?
    Put a small piece of MDF flat (maybe 10 x 14 or so) on the floor, then use a set of speaker spikes to give the speakers a more stable footing ...
    That's a pretty cheap test to see if you get an improvement
    Hi Heather!

    Admittedly, she has a really cheap receiver, that I bought her.... The receiver had a dock for her Ipod, so that's how that happened. I did have my recently purchased Adcom 555 hooked up over here...it still sounded pretty horrible. I am dealing with alot of less than great components here, but it's my second home .

    The house is an 80's tri-level. There is a crawl space below the living room. Upstairs on the other side of the house, like in the shower, the bass is great. This leads my to believe that it isn't really a power issue. The speakers used to have spikes, but I took them off for her floors and put on some felt pads. I think that some improvement can be made, but I'm wondering how much of a problem the room itself will be, or if it's a lost cause....

  4. #4
    Moderator hjames's Avatar
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    We do have a friend here - we jokingly say his home is "... the place where bass goes to die" because
    despite great amps and subs and such, he just doesn't get the pounding bass we'd expect from his quality gear.
    Its partly the shape of the rooms in his home, and a dining room off one side of the living room and a window wall on the opposite side ...
    and maybe the wood floor with basement underneath "helps" too ...

    Well, since you already have spikes, I'd get some MDF pieces to put under the speakers so you can spike them without harming the floor and see if that helps ...

    There's only so much you can do in someone else's home with audio treatments ...

    Quote Originally Posted by pathfindermwd View Post
    Hi Heather!

    Admittedly, she has a really cheap receiver, that I bought her.... The receiver had a dock for her Ipod, so that's how that happened. I did have my recently purchased Adcom 555 hooked up over here...it still sounded pretty horrible. I am dealing with alot of less than great components here, but it's my second home .

    The house is an 80's tri-level. There is a crawl space below the living room. Upstairs on the other side of the house, like in the shower, the bass is great. This leads my to believe that it isn't really a power issue. The speakers used to have spikes, but I took them off for her floors and put on some felt pads. I think that some improvement can be made, but I'm wondering how much of a problem the room itself will be, or if it's a lost cause....
    2ch: WiiM Pro; Topping E30 II DAC; Oppo, Acurus RL-11, Acurus A200, JBL Dynamics Project - Offline: L212-TwinStack, VonSchweikert VR-4
    7: TIVO, Oppo BDP103D, B&K, 2pr UREI 809A, TF600, JBL B460

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    Senior Member louped garouv's Avatar
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    maybe sliding the speakers into the corners of the room itself could help?


    Is the bass in the adjacent room
    (behind the short wall to the right of the TV & vase) better?

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    Senior Member pathfindermwd's Avatar
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    Quote Originally Posted by louped garouv View Post
    maybe sliding the speakers into the corners of the room itself could help?


    Is the bass in the adjacent room
    (behind the short wall to the right of the TV & vase) better?
    No, not really. Now, if I move up to the top of the carpeted stairs, the bass is up there, the sound is better too. If I keep going away from the stereo into the bedroom and bath, the sound is muffled, but all the highs and lows are audibly more balanced, and coherent. It isn't boomy, but the bass is very audible. There are no curtains in the house, only wooden blinds, I see this as a problem too.

    "... the place where bass goes to die"

    Yeah, that sounds kind of like here too.

    The room is very excitable and none of the highs or lows sound good. I wonder if this wouldn't be a good room for smaller full range speakers with a sub or two, to keep the acoustic energy down.

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    Senior Member pathfindermwd's Avatar
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    Quote Originally Posted by Lee in Montreal View Post
    Just looking at the first pictures, here are a few thoughts.

    Big room with high ceilings. Lots of air to energize and that absorbs bass
    Looks to be even more space on the other side of that wall. More air to energize
    Walls and floors seem to be "hard" and highly reverberative

    Meaning bass is absorbed by a huge volume and mids are amplified by the hard surfaces. You got the worst of both worlds.

    Perhaps a sub (or two) can help.
    Thanks Lee. The room dynamics was not only something I thought was an important part, but also what I hoped to understand better. The big tall wall/room makes sense for bass loss, and the midrange is amped and scattered by the floor.......it seems.


    Quote Originally Posted by BMWCCA View Post
    Just connect a 1.5v battery to the input terminal and make sure the same polarity offers the same reaction on the LE14 on both speakers. You don't need to open anything to do that. They're probably correct but it's an easy test to perform and then you can move on.
    Ok, I did the battery test BMWCCA (BTW I have always wondered what it stood for?) These are the 2214's not the LE14's though. I just used a AA and touched the positive to the positive input of the speakers wire's, both woofers went in. So, at least that much is right. I opened them up and everything looks ok. The crossovers and L-pads came to me all hooked up, all I did was extend the wire to the drivers, that all seemed fine.

    I also switched the input wires to one speaker. It was kind of hard to tell at first, but then I could here that the stereo imaging was not in sync. The woofers seemed to hit a litter harder in the lower midrange, but lacked deep bass. It wasn't as obvious an effect as I would have thought, but it was a bit more obnoxious.

    Someone else might not hear they're sound as bad, but having heard these speakers in my house, I know how different they can be, how good they can be.

    Has anyone else had a room they had to dial the L-pads way down for? What are typical JBL monitor L-pads ranges?

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    Senior Member herki the cat's Avatar
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    Quote Originally Posted by pathfindermwd View Post
    .... I did have my recently purchased Adcom 555 hooked up over here...it still sounded pretty horrible.... I think that some improvement can be made, but I'm wondering how much of a problem the room itself will be, or if it's a lost cause....
    The "Fletcher-Munson Curves" Reverberation Tutorials bellow will explain why your under damped huge room has no bass.

    First note that a comfortable average loudness level of 80 db-C is typical, but perceived loudness depends on two items.

    #(1)The sound pressure level(SPL), and #(2) the duration of the sound as defined by the reverberation time constant(RT60)which adds "very loud" duration to the audio signals.

    In your live room the RT60 time constant may be as high as 3 seconds which will increase the perceived mid frequency spectrum loudness by as much as 25 to 30 db due to the reverberation duration which continues to stimulate your hearing, forcing you to reduce the volume at least 20 or 25 db, which according to the "Fletcher-Munson Curves results in approximately 30 to 40 db decrease in perceived loudness of the bass.

    The Tutorials on #(1)Reverberation & #(2)The "Fletcher-Munson Curves"

    #(1)...In acoustics the reverberation time at a particular frequency is defined as the time taken for sound to decay by 60 dB; often abbreviated "RT60" or from the first 20 dB or 30 dB of decay [T20 or T30]. If the overall RT60 is more than 1.5 seconds, the room acoustics will be "live" and echoy.

    Too little reverberation and sound does not travel well throughout the room ,& the acoustics are dead and rather unpleasant. Too much reverberation and clarity is lost in a confusing "mish-mash" of echos.

    "The optimum reverberation time is given at 500 Hz. Important for music, the reverberation at low frequencies should be increased so that the time constant at 125 Hz is up to 1.5 times the value at 500 Hz.

    Reverberation sound components propagating through air, in the process of bouncing back and forth in random modes off the acoustic environment boundaries, do experience increasing attenuation at a rate of 6 db per octave with increase in frequency.

    In other words, the reverberation field density increases inversely to frequency, yielding a magnificent warmth in the lower frequencies all the way down to the sub bass.

    Unfortunately this feature is corrupted when you need to reduce the amplifier gain drastically to bring the mid band frequencies under control in a very live room.

    I remember in 1960, I made a recording with an Ampex 350 tape recorder in a large church here with the floor totally covered with a huge rug. All the seating was fully covered with plush upholstery. We had nearly 100 percent audience attendance.

    Note that each person in attendance provides the acoustic absorbsion equivalent of one open window. In the playback of that tape, the bass was simply stunning.

    #(2)...The Equal-Loudness Contours often referred to as "Fletcher-Munson curves" were developed by Bell Laboratory researchers in the 1936 Worlds Fair on some 1000 hearing subjects. Loudness levels are arrived at by reference to equal-loudness contours of sine waves of differing frequencies. An equal-loudness contour is a measure of sound pressure (db SPL), over the frequency spectrum, for which a listener perceives a constant loudness.

    You can see here that "Perceived Loudness" depends on the SPL of the sound, and as the SPL decrease, the perceived loudness of frequencies below 1,000 Hz, decrease rapidly while the midrange loudness remains proportional to the sound level pressure.

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    Senior Member pathfindermwd's Avatar
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    Quote Originally Posted by herki the cat View Post
    The "Fletcher-Munson Curves" Reverberation Tutorials bellow will explain why your under damped huge room has no bass.

    First note that a comfortable average loudness level of 80 db-C is typical, but perceived loudness depends on two items.

    #(1)The sound pressure level(SPL), and #(2) the duration of the sound as defined by the reverberation time constant(RT60)which adds "very loud" duration to the audio signals.

    In your live room the RT60 time constant may be as high as 3 seconds which will increase the perceived mid frequency spectrum loudness by as much as 25 to 30 db due to the reverberation duration which continues to stimulate your hearing, forcing you to reduce the volume at least 20 or 25 db, which according to the "Fletcher-Munson Curves results in approximately 30 to 40 db decrease in perceived loudness of the bass.

    The Tutorials on #(1)Reverberation & #(2)The "Fletcher-Munson Curves"

    #(1)...In acoustics the reverberation time at a particular frequency is defined as the time taken for sound to decay by 60 dB; often abbreviated "RT60" or from the first 20 dB or 30 dB of decay [T20 or T30]. If the overall RT60 is more than 1.5 seconds, the room acoustics will be "live" and echoy.

    Too little reverberation and sound does not travel well throughout the room ,& the acoustics are dead and rather unpleasant. Too much reverberation and clarity is lost in a confusing "mish-mash" of echos.

    "The optimum reverberation time is given at 500 Hz. Important for music, the reverberation at low frequencies should be increased so that the time constant at 125 Hz is up to 1.5 times the value at 500 Hz.

    #(2)...The Equal-Loudness Contours often referred to as "Fletcher-Munson curves" were developed by Bell Laboratory researchers in the 1936 Worlds Fair on some 1000 hearing subjects. Loudness levels are arrived at by reference to equal-loudness contours of sine waves of differing frequencies. An equal-loudness contour is a measure of sound pressure (db SPL), over the frequency spectrum, for which a listener perceives a constant loudness.

    You can see here that "Perceived Loudness" depends on the SPL of the sound, and as the SPL decrease, the perceived loudness of frequencies below 1,000 Hz, decrease rapidly while the midrange loudness remains proportional to the sound level pressure.


    Wow! I didn't expect such an effort, Thanks!! It may take me awhile to fully comprehend what you have put out there for me. I hope you don't take offense to my ignorance. When you say "forcing you to reduce the volume" do you mean on the receiver, on on the L-pads? When I turn down the high and mids, the bass is essentially turned up in comparison to mid-range loudness. This helps. Too little reverberation is where I am currently at with the mid and high turned down. The room offers little hope for balance, at least I can get the reverberation and the loudness turned down, and get some bass going. It's not perfect for sure....

    Thanks again, you are a scholar, and a gentleman..

  10. #10
    Senior Member herki the cat's Avatar
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    Quote Originally Posted by pathfindermwd View Post
    Wow! I didn't expect such an effort, Thanks!! It may take me awhile to fully comprehend what you have put out there for me....when you say "forcing you to reduce the volume" do you mean on the receiver or on the L-pads?.....
    Many thanks for the kind words!

    I refer to...."forcing you to reduce the volume on the receiver".... This does cut the bass perceived by the human ear more rapidly__ as described by the "Fletcher Munson curves"__ than the volume control reduction of the mid high frequencies as indicated by "Fletcher Munson curves."

    Mother nature is very clever, and very intolerant. Our hearing is most sensitive in the mid high frequencies due a resonance in the ear cavity leading to the ear drum and it rings like a pipe organ pipe.

    There is a good reason for our low frequency sensitivity declining more rapidly than the mid frequencies at lower SPL, because low frequency energy severely masks the higher frequency perception. My best, herki[Quote/]

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    Senior Member pathfindermwd's Avatar
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    Quote Originally Posted by BMWCCA View Post
    A simple battery test takes the the ears (and room) out of the equation. (1.5v battery please)
    Quote Originally Posted by Fort Knox View Post
    Try reversing the wires on one speaker
    Quote Originally Posted by Jonis View Post
    Hey Pathfindermwd, any chance you have a phase/polarity problem that is cancelling out some of your bass response? I accidentally reversed polarity on one of my 2235H's recently and was wondering where my bass had gone in my 4430's.


    Hey guys, good point. A speaker out of phases could produce low bass, and sound pretty awful, I agree. I rechecked the wires from the receiver to the speakers, they look right...though, I'm not sure I would mention it if they didn't

    Internally, I made all the connections, and they should be right...

    I really think that it's the room acoustics, but there is no denying what you guys are saying and now I'll doubt myself until I open everything up and verify that everything is connected properly. I let you know if I find a blunder anywhere.

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    Senior Member BMWCCA's Avatar
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    Just connect a 1.5v battery to the input terminal and make sure the same polarity offers the same reaction on the LE14 on both speakers. You don't need to open anything to do that. They're probably correct but it's an easy test to perform and then you can move on.
    ". . . as you have no doubt noticed, no one told the 4345 that it can't work correctly so it does anyway."—Greg Timbers

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    Senior Member Lee in Montreal's Avatar
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    Just looking at the first pictures, here are a few thoughts.

    Big room with high ceilings. Lots of air to energize and that absorbs bass
    Looks to be even more space on the other side of that wall. More air to energize
    Walls and floors seem to be "hard" and highly reverberative

    Meaning bass is absorbed by a huge volume and mids are amplified by the hard surfaces. You got the worst of both worlds.

    Perhaps a sub (or two) can help.

  14. #14
    Senior Member herki the cat's Avatar
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    Hardwood Flooring Acoustic Help

    With due respect and courtesy to everyone, this living room appears to be quite massive and under-damped and what you hear is massive, uncontrolled, masking reverberation. This room requires the large scale wall & ceiling treatment you find in a typical movie theater, or a $10,000 high end dealer's acoustic demo room__ or treatment with the very efficient acoustic tiles shown in Macaroonie's posts #1 & 2, and a recording studio shown in post #4 of Thread: Acoustic Tiles UK which you can click in.

    In case any case, you would benefit by moving the audio system and speaker in question to a small bed room to evaluate the speaker in question.herki[quote']

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    Senior Member BMWCCA's Avatar
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    Umm, forgive me if this sounds ignorant, but aren't the L100S (like the L100T/3) rear-ported reflex cabinets? How close to the wall do you have them? They need to be at least 12-inches from the wall. The manual for them probably recommends even more.

    Just a thought.



    Well, I just checked and the T3 owners manual doesn't really give that advice, but then it doesn't contain much of any information. The L1,L3,L5,L7 manual goes into much greater detail, and they're rear-ported, too. In fact that manual recommends the speakers be placed three-feet from the rear wall.
    ". . . as you have no doubt noticed, no one told the 4345 that it can't work correctly so it does anyway."—Greg Timbers

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