Need Recommendation for New House / Room

[MeanderingMouse]

Hi all,

First, I'm new here...hola!

Okay, I just bought a new house and I think I am about to run into an acoustic nightmare for my beloved *home theater system*. Right now, I'm in a standard ceiling height home with all carpeted floors. The size of the room and features make for a near perfect acoustic environment with what I'm running:

Marantz AV9000 Pre/Pro
Marantz MM-9000 Amp 170wattx5
Klipsch Reference Series Towers
Klipsch Reference Series Center
Klipsch Synergy Series Tripole Rears
Klipsch Synergy Series 15" 650W Sub

The new room I'll have is a monster. 20x16 with 11 foot ceilings and stressed pine (all wood) floors. The room also features some funky angles off to the sides. I've read in more than one review that ML's are excellent at handling high ceilings and side wall features due to how the sound is imaged. First, is this true?

My Klipsch speakers are work horses and, to me, sound great. The horn loaded Klipsch speaks are notoriously bright and somewhat direct speakers. I'm thinking these are going to sound like crap in this huge room with wood floors and high ceilings.

I've always loved the way ML's seem to fill the room with sound imagery and feel that they might be the right fit for the new room. When I last demo'ed a ML system, it sounded as if sound was coming from EVERYWHERE....it was a completely omni-directional assault that came off 100% transparent...beautiful stuff.

I was looking at the following:

Vista Fronts
Stage Center
Vignette Rears

However, the following fits my budget MUCH better:

Source Fronts
Matinee Center
Vignette Rears

The Vignettes are a must since my pre-wired home has the wire knockouts on the ceiling. That hinge on the Vignette will be perfectly suited to be mounted in the ceiling and then angle the speaker down towards the listening area.

So, is the budget list there a viable option for my new large room with wood floors and high ceilings. I know very little about acoustics but I just have a feeling that these bright Klipsch speakers are going to create a cacophony of bad sound in that room.

Any advice would be appreciated.

Thanks,
Jeff

 

[kcl]

Wow, that is a big room. I'm sure others far more qualified than I will jump in here with advice, but I believe Martin Logan speakers will perform superbly in there.

Just to be sure you're aware, one of the primary reasons MLs do so well in large rooms is not generally known outside of ML owners: From a sonic standpoint they're a line source rather than a point source. Mathematically, the volume drop-off from a point source (i.e., cone speakers) is inversely proportional to the square of the listening distance, while that of a line source (ML speakers) is directly proportional to the listing distance. That is, if you double the distance between you and a cone speaker (point source) the volume is one-quarter, whereas from a ML speaker (line source) its only one-half (or one-ninth vs one-third for three times the distance, and so forth). This is the reason it is often said that Martin Logans fill up a large room.

 

[MeanderingMouse]

Wow, that is a big room. I'm sure others far more qualified than I will jump in here with advice, but I believe Martin Logan speakers will perform superbly in there.

Just to be sure you're aware, one of the primary reasons MLs do so well in large rooms is not generally known outside of ML owners: From a sonic standpoint they're a line source rather than a point source. Mathematically, the volume drop-off from a point source (i.e., cone speakers) is inversely proportional to the square of the listening distance, while that of a line source (ML speakers) is directly proportional to the listing distance. That is, if you double the distance between you and a cone speaker (point source) the volume is one-quarter, whereas from a ML speaker (line source) its only one-half (or one-ninth vs one-third for three times the distance, and so forth). This is the reason it is often said that Martin Logans fill up a large room.

Thanks for the knowledge...that really helps. From my one demo of MLs, I could just tell they would fill a larger room more effectively...the more transparent nature / less direct sound just did it for me.

This explanation of Electrostatic tech pretty much sums up the solution to my problem. The open angles and open space of the side walls and the high ceilings are really made less of an issue with ES technology:

****snip*****
Another key attribute of an electrostatic speaker is its naturally dipolar radiation pattern. A true dipole transducer radiates with equal intensity from the front and back of its diaphragm, but the outputs are in opposite phase. As a result, sound waves rippling out toward the sides meet at the speaker's edge and cancel. That and the relatively large size of a typical electrostatic panel cause output at the sides to be very low relative to that of a conventional loudspeaker, which in turn minimizes side-wall reflections that tend to muddle sonic detail and stereo imaging. While the reduction in output to the sides contributes to the astonishing clarity for which electrostats are revered, the energy reflected off the wall behind the speaker opens up and deepens the sound.
*************

This explains why I have read so many reviews online that says these speakers, when properly placed away from the rear wall, have the ability to deal with less reflecting sound off to the sides and high ceilings.

I noticed that not many people on this forum have said much about the latest Source MLs. I know they are the cheaper of the bunch but I'm hoping they aren't spoken about as much on here only because they are relatively new to the market. I'm going to head over to Magnolia to take a listen myself. I'm sure they won't have them hooked up to a nice separates config like I have in my home theater setup...probably have it hooked to some massive Denon All in One Receiver. I'll never go back to all in one's after experiencing the separates. I really enjoy separates...lovely stuff.

 

[JasonR]

Will this system be used for only TV & movies, or will you listen to 2-channel music very much as well?

- Jason

 

[Gordon Gray]

Hi Jeff,

Had a brief chance to listen to the Source at a Best Buy store in Milwaukee. As expected, speakers were not set up properly, etc. However, my initial reaction was quite positive. The Source has the ML "house sound" with a full bodied presentation in the mid / lower bass region.

In addition, they are quite elegant (read small) compared to the other ML models so they should be quite attractive and unobtrusive in any room.

Good luck with your journey. Remember not to "shave" dollars on the ancillary equipment (including the interconnects between your pre and the speakers) feeding the Source. An appropriate investment in that area, within your budget, will certainly be worthwile.

In addition and FWIW, I've had the SL3's and now the Summit in a somewhat bright listening room and have found the room to not be a significant deficit.

There may be an issue regarding the room size and the Source depending on your desired volume preference.

GG

 

[Rich]

It is true that Martin Logans interact less with walls, floors, and ceilings than a lot of cone speakers. They should perform quite nicely in your large room. But realize that they can still sound somewhat bright if the room is completely reflective. A rug on the floor or some absorbent wall hangings or acoustic panels will do much to improve the listening experience.

In your size room, I would be less concerned with whether the panel can fill the room with sound, and more concerned about the woofers. That is one reason I would urge you to at least consider the Vantage over the Vistas. Also, if you haven't already, please consider buying used. I know there is a pair of vistas, a stage center and two pairs of frescos for sale right now in the classified section of this forum and on Audiogon.

What do you plan to do about a sub? Are you going to use your Klipsch?

 

[MeanderingMouse]

Will this system be used for only TV & movies, or will you listen to 2-channel music very much as well?

- Jason

Bout 90% Movies...I could care less about sound for TV.

 

[MeanderingMouse]

It is true that Martin Logans interact less with walls, floors, and ceilings than a lot of cone speakers. They should perform quite nicely in your large room. But realize that they can still sound somewhat bright if the room is completely reflective. A rug on the floor or some absorbent wall hangings or acoustic panels will do much to improve the listening experience.

In your size room, I would be less concerned with whether the panel can fill the room with sound, and more concerned about the woofers. That is one reason I would urge you to at least consider the Vantage over the Vistas. Also, if you haven't already, please consider buying used. I know there is a pair of vistas, a stage center and two pairs of frescos for sale right now in the classified section of this forum and on Audiogon.

What do you plan to do about a sub? Are you going to use your Klipsch?

Yes, I was going to stick with the sub I have now. It's relatively new and quite powerful.

 

[Bernard]

...........Mathematically, the volume drop-off from a point source (i.e., cone speakers) is inversely proportional to the square of the listening distance, while that of a line source (ML speakers) is directly proportional to the listing distance. That is, if you double the distance between you and a cone speaker (point source) the volume is one-quarter, whereas from a ML speaker (line source) its only one-half (or one-ninth vs one-third for three times the distance, and so forth). This is the reason it is often said that Martin Logans fill up a large room.

Can someone please explain this to me scientifically as I am still in the dark as to why this is so....i.e. how do the laws of physics change for sound propagation in free air when you change the type of the source of the sound ?

Also, how does this impact a hybrid such as my SL3s, where you have a line source AND a point source? The system would sound really unbalanced (no bass relative to the highs) as you moved farther from the speaker, and that is not the case with my system.

I am skeptical about this.

 

[kcl]

Can someone please explain this to me scientifically as I am still in the dark as to why this is so....i.e. how do the laws of physics change for sound propagation in free air when you change the type of the source of the sound ? ...

I am skeptical about this.

Good heavens, the laws of physics don't change, but they do define the different characteristics of wave propagation in a medium for the two significantly different sources. I don't remember the specifics, but I first ran across this back in the late '60s, early '70s while pursuing my Chemical Engineering degree. However, googling on "sonic line source" I found this "Sound Propagation" paper. It includes the following excerpt:

1. Geometric Spreading

This refers to the spreading of sound energy as a result of the expansion of the wavefronts. Geometric spreading is independent of FREQUENCY and has a major effect in almost all sound propagation situations. There are two common kinds of geometric spreading: spherical and cylindrical spreading. Sound propagation losses due to spreading are normally expressed in terms of x dB per doubling of distance from the source. See: FREE FIELD, SIMPLE SOUND SOURCE.

For example, in the case of spherical spreading from a point source, which is due to a noise source radiating sound equally in all directions, the sound level is reduced by 6 dB for each doubling of distance from the source (see INVERSE-SQUARE LAW). A busy highway approximates to a line source, that is, equal sound power output per unit length of highway. A line source will produce cylindrical spreading, resulting in a sound level reduction of 3 dB per doubling of distance. See: SOUND TRANSMISSION LOSS.

You can click on the link and follow the upper-case hyperlinks in the paper for mathematical details. Hope this helps.

 

[Rich]

Also, how does this impact a hybrid such as my SL3s, where you have a line source AND a point source? The system would sound really unbalanced (no bass relative to the highs) as you moved farther from the speaker, and that is not the case with my system.

Remember, a woofer is going to act differently due to the longer wavelengths of low bass waves. With your woofer, the interaction with room acoustics will affect the loudness of the bass at any given location much more than point source vs. line source considerations. In fact, it is not unusual to hear louder bass near the back wall of the room than you hear four feet in front of the speaker. This is due to standing wave peaks and nulls forming in the bass response.

 

[Bernard]

Good heavens, the laws of physics don't change, ..............

You obviously missed that my question was tongue-in-cheek; I did not expect that the laws of physics change. The statement about line vs point source was also in another thread, but with a wish-washy explanation, hence my skepticism. Thanks for the links.

 

[kcl]

Bernard - Yeah, I knew it was tongue-in-cheek. I should have put a smiley so you could see that.

 

[kcl]

I had some time last night and I looked at the math in the paper I referred to Bernard, and its pretty theoretical. I think there's a more intuitive and practical way to describe the difference between point and line sources. (If you don't really care, just skip this message. )

If you think about it, the 'sound energy' from a point source at any given instant in time will spread out over the surface of a sphere, while the sound energy from a line source will spread out over the surface of a cylinder. Additionally, the 'volume' you hear is directly related to the 'sound energy' received at a listening position, and the amount received is the total generated at the source divided by the surface it has to be spread over. Finally, the surface area of a sphere is calculated as "four times pi times R-squared" (don't know how to create equations here), where R is the radius, while the equation for the surface of a cylinder (ignoring the 'ends') is "two times pi times R times H", where R is the radius and H is the hight of the cylinder.

So, given that R is essentially the listening distance, you can see that dividing by the surface area of a sphere (point source) will reduce the volume relative to the square of distance, while dividing by the surface of a cylinder (line source) reduces it relative to just the distance.

Hopefully, this wasn't as confusing as the equations in the paper and was helpful to some.

 

[JonFo]

Line Array theory is not simple.

One of the challenges is that it is based on destructive/reinforcing interference models. That is, where many drivers, or in the case of the ESL, many cells are stacked tightly and all are driven with the same signal.

The resulting comb filtering (normally a bad thing) results in destructive interference killing off the vertical lobes of the radiation and the constructive interference reinforcing the horizontal dispersion. So this combing is what gives both the directivity and the energy focus to the wavefront.

In ESL's like ML's, the line array is really only effective from crossover frequency on up (250 to 450Hz), at and below those points, it's essentially the same as any box speaker. But as noted, those frequencies are omnidirectional, and are subject to room reinforcement/cancelations, which usually means, their bass is able to keep up (depending on placement).

Another thing to remember is that air itself is an absorber, so all line arrays will suffer a decrease in high frequencies proportional to the distance.

For instance, at 4Khz, one would lose 2.7 db due to distance at 4m relative to 2m, but if we factor in air resistance as well, it’s more like a 3.1dB loss. The higher in frequency one goes, the more the air resistance factors. This why most measurements of ESL’s show a drop in high frequencies when taken at 6meters.

Plenty of material and discussion on line arrays over here at the LineArrays AudioCircle:
http://www.audiocircle.com/circles/index.php?board=127.0

 

[Kruppy]

For instance, at 4Khz, one would lose 2.7 db due to distance at 4m relative to 2m, but if we factor in air resistance as well, it’s more like a 3.1dB loss. The higher in frequency one goes, the more the air resistance factors. This why most measurements of ESL’s show a drop in high frequencies when taken at 6meters.

Jonathan,
I've noticed you have posted a couple of times "typical ESL drop off" when refering to high frequency response curves and was about to ask you why, becasue I see the same drop-off on my sweeps measureing at 13.5 feet. You answered before I got a chance to ask. :bowdown: