AudioNervosa

Systemic Development => Psycho-Acoustics => Topic started by: rollo on February 20, 2019, 08:19:43 AM

Title: Building a Room for a Particular Speaker
Post by: rollo on February 20, 2019, 08:19:43 AM
    How does one go about doing that ? What specs of speaker are needed ?


charles
Title: Re: Building a Room for a Particular Speaker
Post by: bpape on March 23, 2019, 10:33:00 AM
Don't think you should need to Charles.  Just need to match the volume to the speaker output.  Don't wanna run ESL57's in a 1000 cubic foot space and don't want to run Infinity IRS in  a 10x12 space.  Just set the speakers and seating in the room in the right places and treat accordingly - diffusion behind dipoles/bipoles, not behind monopoles, etc.
Title: Re: Building a Room for a Particular Speaker
Post by: rollo on May 15, 2019, 10:53:31 AM
  Thanks Brian. That sounds just too simple. Are you saying that a room build around proper ratios [ Say Cardas as an example] is all one needs ? Then treat accordingly ? What I'm getting at is say I own single driver speakers with built in subs. We then could not optimize the room size or shape according to the dispertion characteristics of that speaker ?


charles
 
Title: Re: Building a Room for a Particular Speaker
Post by: P.I. on August 23, 2019, 12:18:14 PM
One of the concerns with rooms is that in America we tend to build rooms with dimensions that are multiples of 4 feet, the typical size of building materials available.  That is good economically, but not necessarily so when it comes to sonics.  Take a typical medium room size:  16' L x 12' W x 8'.  I've come across a lot of these here in Albuquerque.  This gives big bumps in room response at 70Hz, 84Hz, 100hz and 116Hz which are problematic in that the 70Hz and 84 Hz lie in "the mud" factor in low frequency response.  You know, that Boom Box kind of LF.  The 100Hz and 116Hz bumps make bass sound thick and mask a lot of low frequency articulation.

Go here to find a great calculator that you can play with and learn a lot:

https://amcoustics.com/tools/amroc?l=16&w=12&h=8&ft=true&r60=0.6

What is handy about this calculator is the ability to hear what problems are generated by convergent modes.  It is a video game for audio nerds like us.

I plugged in the dimensions listed above.  By varying the dimensions 1' at a time you can see and hear the difference that say a false wall can give.

Also, check out 'Tools' for a quick education in acoustic room theory.

Here is a site that deals with how to trap using Helmhotz resonators to suck out the really nasty room modes. 

http://web.archive.org/web/20010803052829/www.headphone.com/EditorialHeadroom/RoomTubes.asp

This has been around for years and is a great resource.

Small changes in room dimensions can reap huge gains in room response and room gain.   :thumb:





Title: Re: Building a Room for a Particular Speaker
Post by: HAL on August 23, 2019, 12:45:19 PM
F Alton Everest has a very good book on building rooms for audio.  Room construction helps as well.

Ended up with a 10'hx16'wx25.2'd room with basically STC83 walls and 6" slab floor.  Dead quiet and easy to hear details.   :D
Title: Re: Building a Room for a Particular Speaker
Post by: rollo on August 23, 2019, 01:03:54 PM
  Great responses thank you.


charles
Title: Re: Building a Room for a Particular Speaker
Post by: Barry (NJ) on August 23, 2019, 01:13:22 PM
Like this Charles?

https://gizmodo.com/horn-subwoofer-takes-up-crazy-mans-entire-basement-5025867
Title: Re: Building a Room for a Particular Speaker
Post by: HAL on August 23, 2019, 01:16:48 PM
Here are some of his books on Amazon.

https://www.amazon.com/s?k=f+alton+everest&ref=nb_sb_noss_1
Title: Re: Building a Room for a Particular Speaker
Post by: P.I. on August 23, 2019, 10:56:34 PM
F Alton Everest has a very good book on building rooms for audio.  Room construction helps as well.

Ended up with a 10'hx16'wx25.2'd room with basically STC83 walls and 6" slab floor.  Dead quiet and easy to hear details.   :D
Rich, what did you do for doors?
Title: Re: Building a Room for a Particular Speaker
Post by: HAL on August 24, 2019, 02:03:45 AM
Dave,
Just a solid wood door.  It is in the basement and not a noisy area to start.

Biggest thing was the hard fiberglass (like OC703 ducts.  No air noise from HVAC. 

None of my measurement mics are quiet enough to measure the background noise level in the room with the door closed. 
Title: Re: Building a Room for a Particular Speaker
Post by: rollo on August 24, 2019, 11:21:20 AM
Like this Charles?

https://gizmodo.com/horn-subwoofer-takes-up-crazy-mans-entire-basement-5025867

  So cool, if I had the room and money oh boy!

charles
Title: Re: Building a Room for a Particular Speaker
Post by: rollo on August 24, 2019, 11:22:40 AM
  But but :) with a DSP speaker is room other than construction type really matter as much ??


charles
Title: Re: Building a Room for a Particular Speaker
Post by: HAL on August 24, 2019, 12:48:25 PM
You need to get the room acoustics correct first, then you can use DSP correction.  That is the best method I have found.
Title: Re: Building a Room for a Particular Speaker
Post by: P.I. on August 24, 2019, 03:35:41 PM
Bottom line is that the room is the single most important interconnect in the entire system.
Title: Re: Building a Room for a Particular Speaker
Post by: rollo on August 27, 2019, 05:54:44 AM
Bottom line is that the room is the single most important interconnect in the entire system.

 Amen Brother.

charles
Title: Re: Building a Room for a Particular Speaker
Post by: Guy 13 on August 27, 2019, 06:44:34 AM
Hi all.
For me it's 50-50.
Room 50% and equipment 50%.
However, a bad room is 0% and bad equipment also 0%.
Of course a room can't be 0% unless your system is in the bathroom
and a system can't really be 0% unless the sound comes out of a iPhone.
That's my way to put it.

Guy 13