Former Audio Asylum member needs help.

[gymphboi]

Former Audio Asylum member needs help with room treatment.

Hi all, first post over here at Audioholics. As a former Audio Asylum member, I'm hoping that this place will be a breath of fresh air to some of the madness that goes on over there.

While I have gotten help over there, much of it has amounted to very little in the end.

I've spent the last three years going through various speakers and receivers

Just to give you an idea, I have had the following in my living room: Coincident Conquests (still own these), Paradidm Atoms, Paradigm Titans, Magnepan MMG, Mirage Omni 60's.

My current setup consists of 5 Omega Loudspeaker TS2's, a Panasonic SA-XR45 receiver, Pioneer DV-563a DVD Player, and Adire Audio Rava Subwoofer. The Omegas are a single driver Fostex design.

I want to take my system to the next level and have been exploring room treatments.

I tried stacking rolls of fiberglass in the two front corners, but really noticed little if any effect. Maybe they were not big enough rolls, I don't know. I also tried the bags of cellulose insulation as well. Again, no discernable difference. I have since returned it all to HD and Lowes.

Previously, I experimented with ceiling tiles, styrofoam panels (not even sure if those are absorbtive), blankets, etc.

Last week I purchased two 2x4 sheets of Auralex acoustic foam. I cut the sheets into pieces and placed 3 pieces behind each speaker, 3 pieces on the one side wall, and two pieces over my fireplace. The room is not symmetrical hence the odd sidewall placement of the foam.

Do I notice a difference? I'm not really sure. Maybe 16 sq. ft. of foam is nowhere near enough to effect one?

The foam definitely has a low WAF, and before I spend the money on something like AcousticsFirst wall panels, I want to make sure I can hear a difference.

The main problem with the room is slap echo. The room is around 4000 cubic ft. It has tiled floors, vaulted ceilings and concrete walls on 2 sides!

I have a 5x8 wool rug on the floor in front of the speakers. The couches are leather, which I realize are not as absorbtive as fabric, but with two kids, leather is king.

So, what I am asking for is help...

When I posed this question over on Audio Asylum, I got responses that ranged from equipment upgrades, to sticking felt dots all over the place.

A few knowledgeable people chimed in and recommended bass traps, but as I stated earlier, I'm not really sure I could hear a difference.

Thanks in advance,

-Tony

 

[JohnA]

Well you need Something

With a room like you have...you need something to help! You most likely have, but check this out first: http://www.audioholics.com/techtips/roomacoustics/index.php

You may want to try larger panels...like 2-4ft. by 8ft tall. You might not have enough material for that size of room.

Good Luck

 

[plhart]

These three articles on room acoustics and sytem calibration are to found in
our "Room Acoustics" section. Look on left-hand side of the home page. These articles are review highlights of the same straight-forward, non-voodoo courses that are taught at CEDIA to aspiring installation professionals. Understand the concepts here and you'll have solid grounding in how to attack your room acoustics problems.

Room Acoustics: Acoustic Treatments
Acoustics 101 Course by John Dahl of THX
High Performance Home Theater Calibration

 

[Audioholics]

Welcome to Audioholics!

Every room is different, but you're dealing with some very basic principles moving forward. Here are some recommendations for getting you on the right track:

- You need to kill slapback echoes as you mention, so lets focus on the main problems
- Mentally tackle bass modes last, after you have a more tolerable room environment
- 1" thick acoustical panels works to 1kHz (almost useless)
- 2" panels work down to 500Hz (better)
- 4" panels work down to 250Hz (now you're getting somewhere!)
- 2" foam stood off the wall by 2" work similar to 4" panels.
- Diffusers help to break up the sound and eliminate some of the direct reflections that may be a problem

Sound travels directionally, as does light - so try this:

- Put a tall thin mirror on the back wall behind the listening position
- Sit in the listening position and turn to face the mirror
- See one of your main speakers? No? Reposition the mirror until you do. If you can see a main speaker from the listening position you've found one of the first reflection points in your room's back wall. Treat that area with 2-4" of acoustical panelling. Repeat for the other main speaker.

Pay attention to your ceiling and floors as well since I think that's part of the problem. Your concrete walls are also most likely reflecting a lot of sound.

You are right to want to try some things first before spending all of that money, but if you place some absorption and diffusion correctly you should really have a "night and day" result with your room.

This is a start - keep posting here and update us. Eventually we'll have more on this subject, inclufding some basic step-by-step guides for treating common problems.

 

[mtrycrafts]

-Tony

Welcome aboard You need to recover your sanity and this is the right place for that

Read all the great articles linked to. As you will see, you started out on the right track with the panel but it was just too small to do anything, especially in that room
Enjoy, and hopefully this time your mony will be spent on the important aspects of audio, not the insanity parts

 

[Rip Van Woofer]

Glad you escaped from the Asylum! In addition to the good suggestions here, may I suggest a book if you really want to bone up on the subject after reading the Audioholics articles: The Master Handbook of Acoustics, fourth edition, by F. Alton Everest.

Also go to the Infinity Speakers website and navigate to their white papers section. Find and download the articles on rooms and speakers by Floyd Toole, PhD. He's a reknowned authority on the subject and has done serious scientific work on speakers and their interactions with rooms (among other things!)

Also see Siegfried Linkwitz's (of Linkwitz-Riley crossover fame, and a reknowned speaker designer) page on listening room acoustics on his Website. (you'll have to drill down some to find it).

Felt dots won't do it, for sure! If you take nothing else away from your reading, remember that "room treatments" can often consist of standard decorative items and furnishings that will have high WAF and do the acoustical job, too.

 

[sjdgpt]

Speaking of WAF

Bookcases.

Lots of bookcases.

Filled with lots of books and stuff.

Diffuses and absorbs.

 

[gymphboi]

Thanks for all the responses!

I think I am going to need a lot more Auralex.

I'm wondering if mounting the Auralex on some sort of wood frame might make sense. That way I could hang them like pictures and take them down when necessary.

Anybody have any experience with the Sonex Foam products from Markertek?
They seem comparable in price to Auralex, but they have an advantage in that they come in white.

Thoughts?

 

[warnerwh]

You can also get acoustic foam from dealers on the internet. DIY bass traps are fairly easy to make. Bottom line is that now you're getting somewhere. Don't worry, once you get the reflections in your room tamed you'll hear the difference. Go to rivesaudio.com and realtraps where they have articles on how to deal with room acoustics. Room acoustics are major, it's the acoustics and your speakers that have by far the largest impact on sound quality. Speaking of AA Rives has a forum there and Ethan Winer and Rives will both be happy to answer your questions. Ethan also has DIY bass traps and his commercial products are actually reasonably priced.

 

[plhart]

Thanks for all the responses!

I think I am going to need a lot more Auralex.

I'm wondering if mounting the Auralex on some sort of wood frame might make sense. That way I could hang them like pictures and take them down when necessary.

Anybody have any experience with the Sonex Foam products from Markertek?
They seem comparable in price to Auralex, but they have an advantage in that they come in white.

Thoughts?

For all intents and purposes the open cell acoustic damping foam offered by most companies is identical in performance. Mineral wool or fiberglass, for the same amount of surface area and thickness, does perform slightly better (by measurement) than foam. That's the "good, better, best" hierarchy. Mineral wool costs more then fiberglass and but both require some sort of acoustically transparent cloth to cover them.

The important fact to remember is that you're trying to get the reverberation time of your room lowered (as described here http://www.audioholics.com/techtips/roomacoustics/roomacoustictreatments.php ) down to the ideal 0.2 to 0.4 millisecond reverberation time. To achieve this goal (or get closer to it) you usually need to block large areas of reflective wall, ceiling and floor with large areas of absorbtive material.

Understand also that diffusers can and should be used (in specific rear areas especially) to add assist in creating a diffuse immersion effect in the hemisphere behind the listening area.

 

[FLZapped]

Glad you escaped from the Asylum! In addition to the good suggestions here, may I suggest a book if you really want to bone up on the subject after reading the Audioholics articles: The Master Handbook of Acoustics, fourth edition, by F. Alton Everest.

I will second the recommendation for this book. I have a copy, it is excellent. I have loaned it to a friend who is trying to convert a warehouse into a combination recording studio and performance space.

BTW - you will find that you can use sheets of compressed fiberglass that is used for constructing AC ductwork. It is a fairly inexpensive alternative to the 1" foam. It can always be covered in cloth.

Creative room decorating can be effective too. Large potted plants, over stuffed sofas, book cases with varied size books all will have both absorbtive and dispersive effects, reducing the need for the more obtrusive dedicated panels.

-Bruce