[John Casler]

For many years I have experimented with listening rooms and acoustics.

From HUGE rooms to Closets and even a spare large bathroom I have placed systems and acoustic treatments of various kinds to see what effect it had on the sound.

Now days, I can walk into "ANY" room from a space as big as Staple Center, to a closet, to a bathroom and I am immediately aware of the sonic qualities and differences of the space. 

Also over the years I have seen many spend large sums of $$ in attempts to treat their room floors, ceilings and walls to reduce reflective interactions that distort the recorded signal.

With my previous experiences, I took a different path and decided to heavily treat the FRONT wall, but instead of attempting to treat the large spaces of the walls and ceiling of a 20 x 30 room, I created a LISTENING CHAMBER that either blocked or filtered significant room reflected sound.

Sitting in this chamber is an aural pleasure even when NOTHING is playing.  It is so silent and calm, it is difficult not to fall asleep.  I also use it for the occasional Transcendental Meditation to an expedient dive into the "pool of peace".

Now this chamber is only likely a doable if you have a truly dedicated MAN CAVE where "anything goes", since it may not be the most attractive aesthetically.

It is also NOT the way to go for HT.  It is High Performance 2 Channel Audio ONLY

But it can cause a true sonic paradigm shift if you want to really hear more closely what has been recorded WITHOUT the additional room distortion that is just impossible to filter out totally.

The frequencies that are affected will depend on the materials used and how they affect those frequencies.  I tend to think my best LISTENING CHAMBERS were composed of 4 QUEEN sized mattresses with a framework that supported them (including one overhead) since they had a broader band interruption and absorption.

I even found a startlingly good result from simply hanging MOVING BLANKET/PADS from the ceiling to surround the listening chair, or hanging them from stands or a homemade framework.

But anyhow, after all the aforementioned chatter, I came across a couple commercial products that can be used to create such a chamber.

They are actually designed to be used for recording studio environments to keep the recording pure.  Well you can use them in reverse.

Here is what they look like, and all you do is add any additional materials you might need to hit any additional band of frequencies you want.  In the upper version you would take the frontal wall/door and place it across the top.

[John Casler]

And a couple shots of the real listening chamber

[mjosef]

Scary looking there John. 
Where do guest(s) sit?

[Hipper]

I listen in a nearfield set up using RM30Ms without wave guides with the wall behind the speakers covered in various Auralex foam, the principle being to use the speakers like giant headphones. I'm selfish so I listen on my own anyway!

The aim is that the sound comes direct to my ears without interference from the room and contents. To estimate this you have to have an idea of the dispersion of the mid range and tweeter panels. I understand the tweeter's is 25 degrees horizontally and 30 degrees vertically but I've no idea what the mid-range dispersion is although I guess it is similar. However, do these dispersion figures refer to the best sound, and that lesser sound can be dispersed wider?

This thinking plus the fact that sounds can reflect off other items, like lamps, suggest the hood is a good idea and as I've got some spare foam I'll see if I can try something on these lines. A complication for me is that I use a Behringer digital equalizer but I can also use this to measure what difference any changes make.

To me this whole idea of altering the room to get the true sound of the source from your speakers is interesting as you also have to ask what exactly was the intention of the engineer that finalised it. Has he made allowances for most people's listening environments - rooms, cars, headphones - not to mention that most people just bung their playing equipment in any convenient spot, or do they consider people with high end set ups like us?

Thanks John.

Incidentally, I'm now using your 'Tallboy' set up, having raised my speakers 17cm higher on wooden blocks and so far I'm liking what I hear. I'll report back on the 'Tallboy' thread in due course.

[coke]

I tried something similar.  My speakers are offset to one side in the room.  Each side has a gik panel.  I experimented with moving the gik panels really close to the speakers.  I was thinking that this would help make them sound more symmetrical because the walls would no long reflect the sound.

Seems to work very well for the high frequencies.

[John Casler]

Scary looking there John. 
Where do guest(s) sit?

Depends on if they are male or female.

Really the "listening chamber" is for High Performance Listening much like a Formula One Racer is for High Performance Racing.

If you want to take on passengers you get an M3 Bimmer and sacrifice a little performance.

[John Casler]

I listen in a nearfield set up using RM30Ms without wave guides with the wall behind the speakers covered in various Auralex foam, the principle being to use the speakers like giant headphones. I'm selfish so I listen on my own anyway!

I don't think setting up your listening position for the best sound selfish, unless your married and you and your wife listen serious together more often than not.

When I have a friend come by I enjoy offering the sweet seat and WOWing them.  I don't need to sit there since I have spent a lot of time in the SONIC COCKPIT.

The aim is that the sound comes direct to my ears without interference from the room and contents. To estimate this you have to have an idea of the dispersion of the mid range and tweeter panels. I understand the tweeter's is 25 degrees horizontally and 30 degrees vertically but I've no idea what the mid-range dispersion is although I guess it is similar. However, do these dispersion figures refer to the best sound, and that lesser sound can be dispersed wider?

This thinking plus the fact that sounds can reflect off other items, like lamps, suggest the hood is a good idea and as I've got some spare foam I'll see if I can try something on these lines. A complication for me is that I use a Behringer digital equalizer but I can also use this to measure what difference any changes make.

Yes the HOOD and the LAPEL tweaks, while looking a bit strange do just that.

To me this whole idea of altering the room to get the true sound of the source from your speakers is interesting as you also have to ask what exactly was the intention of the engineer that finalised it. Has he made allowances for most people's listening environments - rooms, cars, headphones - not to mention that most people just bung their playing equipment in any convenient spot, or do they consider people with high end set ups like us?

In general, no engineer can approximate the various combinations found in all the different listening environments.  In general they mix with Studio Monitors in the nearfield and Headphones.

Some of the audiophile oriented labels may engineer for audiophile systems.

Thanks John.

Incidentally, I'm now using your 'Tallboy' set up, having raised my speakers 17cm higher on wooden blocks and so far I'm liking what I hear. I'll report back on the 'Tallboy' thread in due course.

A lot of RM30 owners like the Tall Boy tweak.  In some systems and rooms, it can be very nice.

[John Casler]

I tried something similar.  My speakers are offset to one side in the room.  Each side has a gik panel.  I experimented with moving the gik panels really close to the speakers.  I was thinking that this would help make them sound more symmetrical because the walls would no long reflect the sound.

Seems to work very well for the high frequencies.

The broadness of the band of frequencies this affects will be determined by the materials used.

In the pictured chambers you see two different approaches.

1) The Auralex (purple) unit uses exceptional thick and dense closed cell foam.  This will not reach really deep, but is effective for a pretty broad band.

2) The second pic shows a more solid (I don't know the material) wall structure with acoustic foam inside lining.

I have used large cardboard shipping cartons (very dense) packed with old clothing, bedding and rags, as well as some of the shipping packing materials.  These then are covered with high density foam, then wedge and egg crate foam, high density moving blankets/pads and regular wool blankets.

This combination of densities along with substantial front wall treatment do an outstanding job.  The Sonic Hologram is pretty startling.

As I mentioned earlier, I have also used spare matresses and box springs that did a rather good job in combination with additional materials.

It is not unlike squeezing the last bit of "light" out of your HT room. 

Contrary to the opinion of many, it does NOT damp out the high frequencies, it makes them much more clear and distinct.  You will hear detail you never knew existed in good recordings, because the ROOM Distortion (reflected sound NOT from the speaker) obfuscates it.

[woodsyi]

I have been there.  My bro in law said, "he is not married." 

[John Casler]

I have been there.  My bro in law said, "he is not married." 

Hi Rim,

Yes, unless you have a MAN CAVE and complete control over it, you likely will have significant resistance to such a listening tool/set up.