[jefemeister]

Quote:

Originally Posted by CSMR Is that what is best, lack of reflections?

Reflections are necessary to give a sense of space, weight, and presense to the sound. The goal is to tame refelctions, not completely eliminate them. This reduces reverberation time (echo) and can help to fix the frequency/phase response of a room. A total lack of reflection would not be considered a good thing and would make music from a stereo lifeless and more headphone-like in presentation. Sort of like inverting the principle behind binaural recordings.

 

[gerG]

Reflections are important in the studio and in the live performance venue. In a reproduction system, I consider most reflections noise. The only exception is the reinforcement in the deep bass provided by the back wall and floor. Corners help in this as well. This works because the reflections are still in phase with the primary signal. Other than that I have no use for wall reflections. It is not necessary for the stereo effect and image. Depth and ambience cues are in the recording, but they typically get paved over by the reflections downstream of the speakers.

This is a matter of personal preference of course. I will also be the first to admit that the engineers who are mastering recordings are not considering some audiocentric nut case listening in an anechoic environment (or at least semi-anechoic). Nevertheless, I have tried semi-anechoic (still had a floor) and I love it! The down side is that it increases demands on speakers. One of the effects of the diffuse reflections in a room is to make speakers sound louder than they really are. There is also no lf boost to help subs, so they need to be flat in that environment.


gerG

 

[spwal]

here is what i do,

I take the pillows that im not using and put them up against the wall propped on the head of the couch.

I slightly crack my blinds, amking them askew.

I put my bar stools in the near corners and put pillows on them.

I put a cusion pillow on top of my tv, slightly forward.

I hang a fleece or a jacket on my torch lamps in the far corners. I put throw pillows behind my listening position and to the left and right of it.

I take everything off the coffe table, or move the coffe table.

Then i do the test. START CLAPPING. See if anything you have done is removing "slap echo". Like how everyting sounds dead in a nice small indie film theater....

I still have alot of slap echo and there is nothing more within reason that i can do to stop it, but im not worried.

Like i said and i speak for all the broke people living in small apartments...not much you can do short of spend a nice chunk of time setting up your speakers well and putting up some pillows on the sides of the room and back of the room.

That will reward you in spades.

and yes, this place was uber uber super dooper uber high end. He told me that the room treatments matter, but at most levels and certianly if cost is a factor there is nothing much to do...

My walls are made of the wood they are made of and nailed with the nails that they used. The ceiling is plastered with the plaster, the floors floored witht he wood.

The amount of control i have over the space is limited, and i agree with all of you 100 percent that you should try to deaden the space given your resources. I'm just averse to the idea of spending money on baffling equipment.

See if you can get some panels on line from like a used movie theater, or experiment with dimpled bed pads-- i even didnt want to spend the 20 bucks for a couple queen sized dimple pads, but i wish someone would get a couple and try them out....

Sean

 

[ooheadsoo]

Actually, now that I think of it, some bad designers do design their speakers around the anechoic on axis response. The infinity paper touches on that.

There are plenty of experiments documenting the effective properties of foam and fiberglass. Foam doesn't do sub 200hz very well at all.

The clap test does not cover bass frequencies where the most severe problems are.

 

[gerG]

Sean, I did try matress foam many years ago. It sort of works, especially if you get the 4" thick hospital grade stuff. I found a supplier, bought a bunch of rolls, and did the live end/dead end thing. Not bad, but still cost more than it was worth. The foam was blue, so that was known as the smurf den. ooheadsoo tipped me off to the value of high density fiberglass. I will be making extensive use of that material, since I haven't seen anything with better acoustic properties for the money, and it is fireproof. Beware foams that do not have a fire rating. Also be careful of what you hang on the torch lamps. Those halogen jobs can set almost anything on fire.


gerG

 

[CRESCENDOPOWER]

There are a lot of great comments so far in this thread. I believe near-field reflections, and standing waves are the number one killer of any high-end rig. The best way to eliminate this is to have a big room with a high ceiling, large width/depth, and keep the speakers away from the back/side walls. Then, you get to hear what your rig really sounds like.

Quote:

Chasing upgrades beyond mid-fi in an average room is pretty pointless for me.

I just shake my head in disappointment when members (no names) spend thousands, and thousands of dollars on high-end equipment to put it in a small room that closely resembles a cube.

 

[ooheadsoo]

Distance from back and side walls needs to be tempered by the speaker's baffle step compensation amount, though. If the speaker does not have a lot of BSC, then it may need the reinforcement from the wall in the 100hz to 250hz area, generally speaking, depending on the width of the baffle.

 

[gerG]

Crescendo, where have you been, and what is up with your post count? Did you roll the odometer over

You can't accuse me of spending too very much, I got a screaming deal on those amps. Come to think of it, all of that stuff was used, demo, or diy.


gerG

 

[CRESCENDOPOWER]

Quote:

Distance from back and side walls needs to be tempered by the speaker's baffle step compensation amount, though. If the speaker does not have a lot of BSC, then it may need the reinforcement from the wall in the 100hz to 250hz area, generally speaking, depending on the width of the baffle.

Absolutely correct! My comments were aimed more towards the people that decide to buy hi-fi speakers that were designed to have some breathing room, and throw them right against the back wall to keep them “out of the way”.

Quote:

Crescendo, where have you been, and what is up with your post count? Did you roll the odometer over

I have no idea what you are talking about. I am a newbie!

Quote:

You can't accuse me of spending too very much, I got a screaming deal on those amps. Come to think of it, all of that stuff was used, demo, or diy.

No, you are certainly not the culprit. Nice amps though!

 

[gradofan]

Alright, I can't really add anything to the thread right now. Seems I'm enjoying the RTi12s so much (and I'm so lazy and busy) that I haven't even moved them since they left the box. Oy, what is an audiophile to do!

I guess that makes this post a thread bump

.

 

[Wolffy]

If I may add something to acoustical treatment of rooms.

Last night I met with a gentleman in Seattle that has a manufacturing shop which has been making RPG panels for quite a number of years. He has extensive experience in manufacturing sound treatment applications.
The reason I met with him is that he wanted to show me a new product that is going to be displayed at the Las Vegas show.
The panels are flat in the back and rounded in the front. Fit and finish is super. They are designed to either be free standing or mounted on the wall.
Extremly light.
Typically are about 3 feet wide and 5 feet tall.
Prices are not firm yet, but he indicated pricing that for the 5 footers, he was looking at somewhere around $200 for a wall mounted and $400 for a free standing.
This is an incredible price. I don't know how well they work but will find out at the show when we use them
The name of the company is Snap Tex.
Will keep you all informed, or if at the show stop in.

 

[gerG]

Wolffy, thanks for the info. Does the new product have any absorptive capailities, or does it require additional material? Also, what is the thickness of the panels?

Gradofan, thanks for the bump/reminder. I have not made any more progress on the room. I need to confirm a couple of design assumptions before I build panels. One key issue is the relationship between LF capability and thickness for my design. A very tempting option is to remove drywall and make use of all of that spece between the wall studs and ceiling joists. It depends on the thickness requirements.


gerG

 

[ooheadsoo]

Since I have rearranged my room to the current configuration, I have noticed that my room is pretty dead, which is the way I like it, I guess. Here's how I figure this. When I'm at a concert in a big hall, it really doesn't matter how many people are blocking my line of sight to the orchestra, standing or sitting anywhere in front of me, really. They can almost smother me and it all sounds the same because of the huge amount of reflected sound that is reaching my ears. In my room, if I just put my hand in the line of sight of the tweeter to my left ear, 1/3 of my soundstage is wiped out. If someone stands between the left tweeter and me, the entire left channel is wiped out. Of course, I do listen in the nearfield so that is a slight factor. I currently have 3 batts of fiberglass in the corners for a little bass trapping and the equivalent of 4 3pcf 2x4' panels of rigid fiberglass on and around the walls behind my speakers. I also have a tiny bit of cotton balls in cloth and paper in the top corners of my room. The floor is carpeted and there is a bed and accompanying comforters etc in yet another corner. Hey, maybe some of the cellos lying around act as resonators, who knows

 

[Wolffy]

gerG,

It will have both absorption and reflection characteristics. I have not personally had the experience of listening to their effectiveness, yet.
But, that will be remedied come this January at the Home Electronics Show in the room we are using. Right now there is a good chance that someone from the manufacturing company will be there to answer questions and take orders.
If not, the show attendees will have to just listen and contact the manufacturer after the show.

Regards,
Michael

 

[ooheadsoo]

I'm guessing the flat part is rigid fiberglass or some other type of absorptive material. Fiberglass is probably the easiest. And the curved part is for reflection, could be any number of materials. The curve will break up standing waves. I still wouldn't buy it for $200 a pop though

Btw, the lighter it is, the less effective at absorbing bass it probably is...