"How-To" topic suggestion thread

[Peter Loeser]

This is something I've been wanting to do for a while, and Tony has already kicked us off with some great how-to's in the stickies. I'd like to create more illustrated tutorials related to system setup, troubleshooting, and maybe even room design, acoustics, etc. I'd also like to do a series that will define and compare different audio and video codecs, playback formats, industry standards, etc to help newcomers wade through all the different acronyms and technologies. There's a ton of options to account for these days just to make sure all of your components will be compatible. So, what I'd love to hear from you guys are some of the most common room design/setup questions and maybe some of the technologies that aren't intuitively easy to understand. Even if it's something you understand well, if you've answered a lot of questions about it, I think it's worth explaining here. As I have time, I'll create writeups and maybe even some video tutorials. There's enough experience within our community to create an extensive library of knowledge. Thanks in advance for your suggestions.

*Full disclosure - I'm far from being an expert at all of the topics I'd like to cover, so please feel free to share any resources you've found helpful. I'd be happy to cite them in the write-ups. The more community participation we have, the better these will be.

Planned topics based on suggestions received so far:
1. How to locate and treat first reflection points
2. How to integrate one or multiple subwoofers into a stereo or home theater system

 

[1_sufferin_mind]

What a great concept, Peter! The suggestions that are sure to be submitted will no doubt add value to the site.
One topic I'd like to see covered in more detail than given in Austin Jerry's guide is HOW TO FIND REFLECTIONS AND PROPERLY TREAT THEM.
The article could include how to identify and treat both beneficial and detrimental reflections using the ETC curve, string technique, etc.

 

[1_sufferin_mind]

Also: HOW TO INTEGRATE A SINGLE SUB or HOW TO INTEGRATE MULTIPLE SUBS. The topic should include instructions for obtaining the best SPL support from a sub or subs through the crossover region. That last step is often unknown to novices, and thus overlooked. A sticky should help curb the multiple, duplicate-topic threads that result.

 

[Peter Loeser]

Great suggestions - essential topics for any enthusiast IMO.

 

[Sonnie]

Excellent ideas!

I think there is now some question as to whether first reflections need to be treated at all. Of course if you have your speakers far enough out in the room away from walls where they likely sound their best, the first reflection will just about be you.

 

[Leonard Caillouet]

Great idea.

 

[Peter Loeser]

Thanks for the feedback. To add to Sonnie's comments - there's no one method that will work for every room. The idea would be to draw people to the site and give them a starting point, then support with more in-depth setup discussions throughout the forums.

 

[Prof.]

There are two conflicting aspects when it comes to acoustic treatment of a dedicated home theatre room..
If given two different size rooms..one very small and the other very large, both with bare boards and plaster wall constructions..Which is going to need more acoustic treatments?

The very large room will have a lot of slap echo when the room is completely empty..but the left and right speakers will most likely be well away from any boundary walls..
On the other hand, the small room will have the opposite scenario..little echo and close boundary walls

As has been mentioned recently..In some acoustic environments, first reflection point panels my not be necessary and may even be detrimental to the audio performance..

In my own case..My recently built theatre in my new house is a little smaller than my previous theatre..and as such has required a slightly different acoustic treatment...

I initially put in the same treatments I had used previously..(wall construction of the two rooms is the same) with first and second reflection point panels which consisted of 5' high 2" thick Ultratel (OC 705) semi rigid fibreglass spaced 2" off the wall..and a rear panel 5' x 3' of the same material only 4" thick..With bass traps front and back..

The first sound tests were very disappointing...Nothing like it used to sound like in my previous theatre!..
Voices were not clear..Bass was lacking any oomph generally and the highs were a little coarse...

I first tried removing the first reflection point panels, since this seems to have improved some peoples setups..

This only made things worse!..particularly voices which lacked any presence..
I also noticed that I was not getting the spread of sound across the sounstage that I had previously..

So I decided to go the other way..I added diffusers and reflectors to the original first reflection point panels and left the second reflection point panels as they were..

The improvement was immediately noticeable..
The soundstage was expansive and had that wrap around feel to it..
Voices were clearly defined across the screen and you could pin point their location..They also had a nice forward presence to them..I even noticed an improved definition to bass sounds!

I guess to sum it all up...There is no such thing as a standard set of rules that can be applied to any room..You can only get optimum sound with careful tuning of the acoustic treatments..
Don't rely on mechanical / electronic devices alone to get the results you require..A good ear goes a long way!

 

[tesseract]

First reflections in larger rooms are more problematic than in smaller rooms by virtue of the time delay induced by the longer path the reflection must take. When the reflection exceeds 4 ms, it starts to become destructive. Absorption in larger rooms helps ameliorate this issue.