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pathfindermwd
12-12-2011, 01:34 PM
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?

540235402454025

hjames
12-12-2011, 01:50 PM
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 ...



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.

pathfindermwd
12-12-2011, 02:03 PM
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...:blink:. 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 :D.

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....:confused:

hjames
12-12-2011, 02:37 PM
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 ...


Hi Heather!

Admittedly, she has a really cheap receiver, that I bought her...:blink:. 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 :D.

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....:confused:

louped garouv
12-12-2011, 02:39 PM
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?

pathfindermwd
12-12-2011, 02:59 PM
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. :dont-know:

grumpy
12-12-2011, 03:55 PM
That's kind of what I was thinking... it would give you some options about where the
bass was emanating from. If you have the option of trying them under the oriental
wall hanging, that might change things (not necessarily for the better, and I understand
that most humans put speakers and TV's where they're out of the way... so that placement
may not be practical). Having L100t's, if they're working properly, they have plenty of bass.
If placement doesn't work... different speakers are probably the best solution.

herki the cat
12-12-2011, 05:23 PM
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 (http://www.audioheritage.org/vbulletin/showthread.php?19824-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']

BMWCCA
12-12-2011, 06:21 PM
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. :dont-know:



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.

grumpy
12-12-2011, 06:32 PM
good point (re port placement). I figured that was kind of obvious, but
then I'm not convinced even stuffing it completely would result in massively
missing bass.

Serious room mods are probably also out of the design parameter space
(can take lots of coin or work to disguise audio room modifiers). Which is
why my suggestion of matching the speaker type to the room, rather than
vice versa.

pathfindermwd
12-12-2011, 07:20 PM
I kind hate to bring this up now because I just said how the L-pads weren't realy doing much. But after I said that "maybe the room needed smaller less excitable sound levels" it got me to thinking how the L-pads should be able to correct for this by turning down the volume of the offending drivers.

So what I did was to lean the speakers back, which not only helps with time alignment, but would also affect how the sound comes off the speaker and hits the floor, and it picks up the woofer a little too. Next, I turned the L-pads down - waaaayy down, more than I ever imagined they ought to be, starting at no sound at all. I think the mid-range is now down about 5 decibels (if I remember the range of the L-pads right), and the tweeters would be down around 4.5 decibels. This is on the low side of the L-pad range that I honestly never imagined I would ever want or need to use. I guess I always figured that the ony way you would use this low setting is if you were tone deaf (or really into bass)! It took a moment to adjust to the sound but sure enough, the noise (cause by all the reflections)is down, the loud mids are turned down in volume which brings forward the bass. As I turn up the volume on the Receiver the bass comes in loud and clear and (as it should) is now shaking items off the wall, the high's (mids) are well tamed. They still lack the excellent dynamic difference I get at home but there is simply not much to be done presently, If the mid-range comes up, it's too noisy. At least it's much more listenable. It could be said that this room is quiet enough (or loud enough) to hear a pin drop.

Surprisingly (perhaps), the tweeter volume only adds a various amount of airy-ness, nothing shrill, rather, it's the mid-range that has the most noisy effect, it seems apparent to me anyway. The GF likes a little bit of highs, she love's these speakers, but like's them alot more now that things are shaking off the walls (which I will not in present company psyco-analyze :) ).

We have also laid down some rugs and blankets on the floor in front of the speakers, and have agreed that when she get's the chance she should add more of them to the room to improve the sound even more. She was surprised I could make them perform though, she had hardly been listening to them. As we got closer to the speakers she could hear and feel how hard they were hitting. I explained that this is how well they should be sounding at distance, no distortion, lots of dynamic energy and clarity, the woofer hitting as hard as I have ever felt it.

"trying them under the oriental
wall hanging"

I think speaker placement is very relevant, but I don't want to change the room around. Not just because it's not my place, but also because it involves alot of furniture relocation :)



"this living room appears to be quite massive and under-damped"

That is exactly the case Herki! It can be difficult to believe...Thanks for understanding!



"They need to be at least 12-inches from the wall."

Absolutely! I have moved them in and out. But bassy-ness or boomy-ness is not really the problem. It's noisy-ness. As I turned down the L-pads mids/highs to super-low numbers bass came through. Not super-clean bass at listening position, but finally..some bass. I am now at the point where I could pull them out to help what boomy-ness is there. A problem I can live with! :)

Thanks for all your helpfulness, I really appreciate it! Thanks to Duanage for the L-pads too! Up till now, they were more of a curiosity that I never really knew how much I would need.

Definitely some fabric room treatments in the future, maybe better equipment, if I can part with them :)

Has anyone else had so much need for L-pads as well?

grumpy
12-12-2011, 07:42 PM
well, well... congrats in making them not only listenable, but satisfying to your understanding GF. :)

pathfindermwd
12-12-2011, 08:19 PM
well, well... congrats in making them not only listenable, but satisfying to your understanding GF. :)


Satisfying might be too strong a word... :applaud: Like us, there is only temporarily pacified. :D

There is always tomorrow to decide to be less than impressed by our devices :banghead:

Jonis
12-13-2011, 03:23 AM
As I turned down the L-pads mids/highs to super-low numbers bass came through. Not super-clean bass at listening position, but finally..some bass. I am now at the point where I could pull them out to help what boomy-ness is there. A problem I can live with! :)


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.

Fort Knox
12-13-2011, 04:58 AM
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?

540235402454025

Try reversing the wires on one speaker

BMWCCA
12-13-2011, 07:04 AM
Try reversing the wires on one speaker

A simple battery test takes the the ears (and room) out of the equation. (1.5v battery please)

pathfindermwd
12-13-2011, 10:09 AM
A simple battery test takes the the ears (and room) out of the equation. (1.5v battery please)


Try reversing the wires on one speaker


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 :p

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.:banghead:

BMWCCA
12-13-2011, 04:21 PM
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.

Lee in Montreal
12-13-2011, 04:40 PM
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. :eek:

pathfindermwd
12-13-2011, 06:15 PM
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. :eek:

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.



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?

Lee in Montreal
12-13-2011, 06:26 PM
... BMWCCA (BTW I have always wondered what it stood for?) .
Could it be BMW Car Club of America?

BTW I have medium size speakers that sound empty and gutless in one room, yet are deep and full in a smaller room.

pathfindermwd
12-13-2011, 06:34 PM
.
Could it be BMW Car Club of America?

BTW I have medium size speakers that sound empty and gutless in one room, yet are deep and full in a smaller room.


DOH! Yeah, that's too rich for my blood, maybe that's why I didn't catch it! :p Seriously though, thought it would be something speaker related. :dont-know:

My L100T(3)'s at home like to be nestled... They have 240ti's flanking them, and a big heavy cabinet in the middle, take them out of there and they don't have the same character..

herki the cat
12-13-2011, 07:03 PM
.... 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....:confused:

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.http://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Lindos1.svg/668px-Lindos1.svg.png (http://upload.wikimedia.org/wikipedia/commons/4/47/Lindos1.svg)

BMWCCA
12-13-2011, 07:17 PM
Could it be BMW Car Club of America?
Yes, we have a winner!

DOH! Yeah, that's too rich for my blood, maybe that's why I didn't catch it! :p Seriously though, thought it would be something speaker related. :dont-know: Some of us have more than one hobby! :thmbsup:

pathfindermwd
12-13-2011, 08:11 PM
Yes, we have a winner!
Some of us have more than one hobby! :thmbsup:

That's Cool! So BMW (:)), you didn't seem to want to chime in on the room acoustics. Not convinced it's the issue?

I kid, but your opinion is valued...

pathfindermwd
12-13-2011, 08:26 PM
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.http://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Lindos1.svg/668px-Lindos1.svg.png (http://upload.wikimedia.org/wikipedia/commons/4/47/Lindos1.svg)



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..

BMWCCA
12-13-2011, 09:11 PM
These are the 2214's not the LE14's though.

Sorry. Still have my mind on Woody's 250ti clone project!

I suppose you could always try your setup in a different room. Probably easier said than done.
Room acoustics seem to be one of the few variables remaining.

herki the cat
12-13-2011, 09:53 PM
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/]

Lee in Montreal
12-14-2011, 04:57 AM
Hey pathfindermwd

My upstair living room looks very much like in your picture. Cathedral ceiling, hardwood. Plus one side opened to a dining room. Even with an 8'x 8' shaggy carpet and fluffy sofas, I couldn't get rid of the reverberation in th mids, which "killed" the bass (proportionally speaking). I removed the TV and sound system from that room. It was too painfull and it made me dizzy. The same system that was awfull in the living room got moved to the bedroom, where it sounded perfect with wall-to-wall carpet and big bed. :D

In your case, if you want to keep some music in there, you'll have to be creative with room treatment.

herki the cat
12-14-2011, 08:27 AM
Hey pathfindermwd

My upstair living room looks very much like in your picture. Cathedral ceiling, hardwood. Plus one side opened to a dining room. Even with an 8'x 8' shaggy carpet and fluffy sofas, I couldn't get rid of the reverberation in th mids, which "killed" the bass (proportionally speaking). I removed the TV and sound system from that room. It was too painfull and it made me dizzy. The same system that was awfull in the living room got moved to the bedroom, where it sounded perfect with wall-to-wall carpet and big bed. :D

In your case, if you want to keep some music in there, you'll have to be creative with room treatment.

Very succinct, Lee in Montreal, your advice to move to a smaller quiet room is right on.herki[Quote/]

pathfindermwd
12-14-2011, 03:50 PM
Very succinct, Lee in Montreal, your advice to move to a smaller quiet room is right on.herki[Quote/]


Hey pathfindermwd

My upstair living room looks very much like in your picture. Cathedral ceiling, hardwood. Plus one side opened to a dining room. Even with an 8'x 8' shaggy carpet and fluffy sofas, I couldn't get rid of the reverberation in th mids, which "killed" the bass (proportionally speaking). I removed the TV and sound system from that room. It was too painfull and it made me dizzy. The same system that was awfull in the living room got moved to the bedroom, where it sounded perfect with wall-to-wall carpet and big bed. :D

In your case, if you want to keep some music in there, you'll have to be creative with room treatment.



Sorry. Still have my mind on Woody's 250ti clone project!

I suppose you could always try your setup in a different room. Probably easier said than done.
Room acoustics seem to be one of the few variables remaining.


I think you guys are saying that I need to relocate the stereo...:D

The only available room would be a spare bedroom, or the kids room, and it aint going in the kids room! He already jabbed a small hole in the mid-range cloth that I will have to solicit advice on how to repair.


It has to stay in there (LR), that's where everything happens. I know there will have to be some modifications to the room which I think the GF is alright with (she actually like's my speaker interests,think's it makes me look cool, for now anyway.. :) )

What I have done in the meanwhile is this 1. Turn down the L-pads to super low numbers to decrease the offensive sound energy/reflection. 2. I have bought 2 wooden footstools 11" high raising the speakers. Raising the mid-range off the floor should help with the sound energy hitting/reflecting off the floor. 3. I am still playing around with tilting them to see if this can help, at this height, or if it will just be beamy. By raising the sound, I am affecting how it reacts with the room/floor a little. At this point, I'll take whatever I can get....:bouncy:

Lee in Montreal
12-14-2011, 04:40 PM
One thing you could try is to change the location of the speakers. Instead of having them facing a very close wall (which probably doesn't help with reverbaration), perhaps you can place them facing a wall that is further away. Basically, perpendicular to their current location.

pathfindermwd
12-14-2011, 05:12 PM
One thing you could try is to change the location of the speakers. Instead of having them facing a very close wall (which probably doesn't help with reverbaration), perhaps you can place them facing a wall that is further away. Basically, perpendicular to their current location.

I agree. If they were up against the window they would have the benefit of some boundary reinforcement for the bass as that is a small cubby. The footstools help. I can't turn up the L-pads, but I do discern better (much better really) balance, more dynamic sounds coming through, less noisy, less muddy. It's a work in progress. Next up is a big area rug in front of the couch, some carpet runners thrown about, curtains, maybe some square foam art for the walls. :D

herki the cat
12-15-2011, 12:36 AM
.... It's a work in progress. Next up is a big area rug in front of the couch, some carpet runners thrown about, curtains, maybe some square foam art for the walls. :D

There is an interesting low tech thing you can try to get a good feel for the mid range reverberation density in your room. More on this a Little later. First, consider that there are many uncontrolled variables in the recorded program material heard in this room, and the acoustic clues vary drastically among the various recordings used."

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 the more simple RT30 to decay by 30 dB. If the overall RT60 is more than 1.5 seconds, the room acoustics will be "live" and echoy."

Using a test tone of 500 Hz, or 250 Hz for music, is traditional for measuring the RT60 or the RT30. This effort requires a sound pressure level meter with built in microphone adequate for measuring RT30, costing approx' $30 to $60 at Radio Shack, plus a logarithmic oscilloscope, a test tone CD, & a transient-free switching device.

Alternately, a "tone-burst" generator plus the SPL meter & the oscilloscope is much more practical.

The low tech approach is to use a single tone in the mid frequency band at 80 or 90 Db SPLaccording to a sound pressure level meter while observing a big clock with a continuously sweeping second hand. Then turn off the test tone at the input to the amplifier and observe how many seconds it takes for the sound in the room to decay to complete inaudibility. This decay time should correspond to an RT30 event. Obviously, if the decay time to inaudibility after signal shut-off exceeds 1.5 seconds, the RT30 reverb hang over is excessive requiring additional damping in the room. herki[Quote/]

herki the cat
12-17-2011, 01:34 AM
.... It's a work in progress. Next up is a big area rug in front of the couch, some carpet runners thrown about, curtains, maybe some square foam art for the walls. :D

This tutorial www.fulcrum-acoustic.com/2010/11/daves thoughts on space, does not address the reverberation problem, but it will explain "what happens with the speaker resting on the floor", and that "Off the floor" changes things significantly. The original post has been slightly revised and is now available in PDF form.

Click this button: Get it here (http://www.fulcrum-acoustic.com/wordpress/wp-content/uploads/2010/11/Comments-On-Half-Space.pdf).

herki [Quote/]

pathfindermwd
12-17-2011, 06:48 PM
This tutorial www.fulcrum-acoustic.com/2010/11/daves thoughts on space, does not address the reverberation problem, but it will explain "what happens with the speaker resting on the floor", and that "Off the floor" changes things significantly. The original post has been slightly revised and is now available in PDF form.

Click this button: Get it here (http://www.fulcrum-acoustic.com/wordpress/wp-content/uploads/2010/11/Comments-On-Half-Space.pdf).

herki [Quote/]

"If however we aim the loudspeaker away from the boundary, then the high frequency output of the
image, or reflected, loudspeaker never arrives on the real side of the boundary see Figure 5. The
low frequency pressure doubles, but the high frequency pressure is not changed at all by the presence
of the boundary. Obviously a surface cannot have an effect on sound that doesn't strike it."

So in the context of my application, this seems to be saying that if you tilt the speaker back, then it would help the reverberation issue by keeping the sound from striking the floor...as it would be aimed away from the boundry.

Of course, this does not speak to how differently the drivers may sound at an angle...

"In both cases any physical separation from the
boundary results in frequency response combing in the direction perpendicular to the boundary."

I do not understand this statement well. What is meant by combing?

Lee in Montreal
12-18-2011, 06:27 AM
Just curious. Have you tried moving the speakers' location yet? Putting them in corners will reinforce bass. Angle them and it will reduce medium frequencies. As realtors say : Location, location, location. :eek:

pathfindermwd
12-18-2011, 06:06 PM
Just curious. Have you tried moving the speakers' location yet? Putting them in corners will reinforce bass. Angle them and it will reduce medium frequencies. As realtors say : Location, location, location. :eek:

Thanks Lee,

I hear what you're saying, speaker placement IS very important. Without turning the LR sideways, there's not much I can do. If it were my place....

If I put the speakers in the corners of the current wall they would probably be 20'-25' apart. I would definitely need longer speaker cable! I doubt that would add a alot of quality though.

Presently the bass isnt bad. The midrange/tweeter are turned down very low, bringing the bass up in comparable volume. It doesn't yet sound that great, but it is better.

I know what the speakers are capable of in a different room, and with better components. I am bummed out to confront the advise of some that say the room just may not ever produce good sound, they may be right, but I'll do what I can to make small but significant improvements. :dont-know:

I appreciate the suggestions..