first order reflections

[TroyTN]

I was wondering if many of you Klipsch owners use and sound diffusion material in your room to widen your soundstage using Klipsch speakers? If so what do you use?

Also I read that one can simply have someone move a small mirror along each side wall until the person sitting in the sweetspot sees the speaker in the mirror and that is where the first sound reflections occur and a sound diffuser should be placed on the wall at ear level and below to better expand the front soundstage. So one would have a sound diffuser on each side wall.

I have even read one should cover the entire front wall with some sort of fabric. Does this apply with horn loaded speakers like Klipsch? Anyone do it and notice a huge improvement?

Thanks

Troy

[lynnm]

I run KLF30's. I built sound absorbing panels that I placed at the point of first reflection,(determined using the mirror technique you describe).

I found that my soundstage is wider and deeper and the sound more detailed and with a smoother midrange. Your mileage may very.

John Risch has published plans for easily built and inexpensive panels:

http://www.geocities.com/jonrisch/index2.htm

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It is meet to recall that the Great Green Heron rarely flies upside down in the moonlight - (Foo Ling ca.1900)

This message has been edited by lynnm on 06-06-2002 at 12:29 PM

[Ray Garrison]

My room is 17 X 21, with a tile over concrete slab floor and solid front and back walls. When I first set up the stereo, I have a HORRIBLE slap echo between front and back. System sounded TERRIBLE. (This was with either La Scalas, CF4 or KG-4 speakers).

I bought some (very inexpensive) semi-rigid fiberglass panels (they have one side covered with a moisture barrier, the other side has the fiberglass exposed) about two inches thick, maybe 4' X 6'. I covered them with heavy black felt, and hung three of them across the center of the front wall, fiberglass side out, behind the TV, entertainment center, speakers and stuff. Totally solved the problem, and looks pretty good.

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Music is art

Audio is engineering

Ray's Music System

[TroyTN]

Lynnm,

So how large did you build your panels and are they hung at ear level and below or just anywhere on the wall at the reflection spot? One on each side wall?

Thanks again

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Troy...

[lynnm]

Hello TroyTN

My panels are freestanding and measure 16" x 48" x6" and I have them at both side walls and also between the speakers. The second set did not produce as dramatic an improvement as the first but created some further improvement nonetheless. It may well be that the second set would create too much damping in a less lively room than mine.

You could certainly easily build smaller panels,( say 2'X 2') and hang them at the point of first reflection at the same height as the tweeeter and mids.

The plans that Jon Risch published are easy to follow and extremely inexpensive to build. The four I built took a buddy and I about 45 minutes each to build and my total cost was about C$100.00

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It is meet to recall that the Great Green Heron rarely flies upside down in the moonlight - (Foo Ling ca.1900)

[j-malotky]

Troy

I like Lynnm's suggestion to start with some small panels and play with there location. Exact locations are hard to recommend since every environment is different. Start out with a few. Try to keep some liveness to your room. If you make it too dead, you will not be as happy.

Here are a few guidelines IMHO:

First off - do not baffle the front of your room. Generally you want the sound to pass by your ears once, and then disperse. That means your baffles should go in the rear and rear sides of your listening position. I have had great luck keeping the front of my rooms, where the sound is generated, live sounding

Sound waves are at a much lower frequency than light waves. Your mirror approach is a starting point, but please remember that sound waves will not bounce the same as light waves.

Sound waves also disperse more from the source than light waves. How do I explain this - Kind of like when you drop a rock in the water, the waves go out in all directions. Not quite the same, but the sound comes off your drivers in a kind of half round pattern, not in a straight line like looking at your speakers reflection in a mirrors.

If you are building a room there are other things you can try before baffles. You can slightly toe in your walls to point slightly down to your carpet in the rear and rear sides of your room. I have also had great results from building rear corners rounded into the room or adding false corners to the back of the room to disperse the sound. If possible - I always try to design my rooms to not have any baffles.

One thing I am itching to try next is to build a room that is diamond shaped to widen the sweet spot.

Lots to try. Have fun with it. You can get some great results when you play around a little.

Let us know how it goes.

JM

[HornEd]

I used heavy curtains and a fabric valence to cut down an overly bright room with two walls being primarily glass.

I also used Front Effects speakers fired by a Yamaha RX V-3000 to balance out room acoustics and widen the sound stage. The Front Effects KLF-C7's also allow me to tuck my Mains close to the 65" RPTV for a better dialogue tie to the screen.

In the music room, I used thick woven tapestries at the point of first reflection using the mirror bit.

Be sure to do your sound balancing act with an SPL meter on your side... the difference between fully calibrated speakers with the correct distance from the wall and just the right toe-in is critical for horn loaded speakers. -HornED

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Photo update soon! -HornEd