Is it even possible?

Ethan Winer · Post by **Ethan Winer** » Thu Sep 09, 2004 2:22 am

RT,

> what thickness of plywood would I use on the back of the trap so it would still be effective at the rated frequencies? <

The thicker and more massive, the better. I'd use at least 3/4 inch thick plywood, and I'd also put cross braces every two feet (they can go on the inside) to further prevent the back from flexing.

--Ethan

rawtunes · Post by **rawtunes** » Thu Sep 09, 2004 9:43 am

.....that's good news!....managed to pick up that copy of EQ and seeing as you're a regular contributor I'll be getting a subscription

....my space is never going to be perfect but after reading a lot more on the subject I believe I can improve it quite a bit....even without splaying walls and floating floors, etc....anyway, I'm gonna do some testing before I make any material purchases....one more question: do you (or does anyone)know if that Sonar 3 download from your site will work in Sonar 1.3?...if not, I do have the Virtual Minirator so maybe I can make do with that....

Ethan Winer · Post by **Ethan Winer** » Fri Sep 10, 2004 3:12 am

R,

No, the Sonar 3 project works in Sonar 3 only, and I assume Sonar 4 when it comes out next month.

--Ethan

knightfly · Post by **knightfly** » Fri Sep 10, 2004 4:21 am

Here's another pretty useful test package (free)

http://www.moonaudio.com/softwar5.htm

at least til you upgrade Sonar

Steve

rawtunes · Post by **rawtunes** » Fri Sep 10, 2004 4:02 pm

Ethan:...yep...I tried it before your reply and it definitely didn't work in 1.3

knightfly:....thanks for the link Steve!...I'll be looking into that...

I was wondering...since I'm in a basement....should I be calculating a room mode based on the dimensions of the foundation walls as far as the bass frequencies are concerned?

knightfly · Post by **knightfly** » Fri Sep 10, 2004 4:07 pm

For modal purposes, you measure to the barrier for the low frequency sound - if all you have in front of the concrete is some type of light weight paneling, then the measurement would be to the concrete - for heavier walls, they would be the boundary... Steve

rawtunes · Post by **rawtunes** » Tue Sep 14, 2004 5:04 am

knightfly:...I tried that link.....for some reason I can't get the spectrum analyzer to run on my set up and I'm leery of installing it on my computer with Sonar....for some unknown reason the ModeCalc on Ethan's site won't work on my internet computer either....any chance someone could get the room mode for 26 X 26 X 7 and post the result back here?...I did some testing and would like to compare figures....thanks for any help!

Ethan:....just wanted to say I enjoyed the article in EQ...thanks to you and Wes Lachot for your efforts!

Ethan Winer · Post by **Ethan Winer** » Tue Sep 14, 2004 7:14 am

RT,

> the ModeCalc on Ethan's site won't work on my internet computer <

It's a very simple DOS program, and you can just run it from my site. When you click the link, select Open rather than Save.

> any chance someone could get the room mode for 26 X 26 X 7 <

I don't have to run that to know there's a problem with the square shape. Unless you're willing and able to change the dimensions by building a wall, knowing the modes is not that useful. I'm attaching a screen capture from ModeCalc so you can see for yourself.

> just wanted to say I enjoyed the article in EQ...thanks to you and Wes Lachot for your efforts! <

Thanks!

--Ethan

rawtunes · Post by **rawtunes** » Wed Sep 15, 2004 5:38 am

Ethan:...regarding running the Mode Calc from your site...I get a dialog which opens and says "system file not suitable for running MS-DOS and Microsoft Windows applications"...

....so thanks for posting the results for me!

I ran some "tests" (probably not very scientific ones at that...utilizing the Virtual Minirator and a pair of SM57's instead of my ears...) at my mix position and found deep nulls at 65hz, 125hz, 200hz, 800hz, 1.6Khz, 2.0Khz, 2.5Khz, 3.15Khz, 6.3Khz....now I'm totally confused...so.....given the bad room mode dimensions of my entire basement would I get any benefit from hanging 4" 703 in the corners?.....I am considering coming up with a design to completely remodel the basement into a control room and two tracking rooms but this would be a tremendous and expensive undertaking that is frought with problems to be overcome to make it work...would merely wrapping some 703 and placing it strategically in corners be of benefit until I research a more permanent solution? (...a simple drawing of my current set-up is on page 1 of this thread)

Ethan Winer · Post by **Ethan Winer** » Thu Sep 16, 2004 1:58 am

Raw,

> running the Mode Calc from your site...I get a dialog <

It has to be on your end. Are you running an antivirus program?

> utilizing the Virtual Minirator and a pair of SM57's instead of my ears...) at my mix position and found deep nulls at 65hz, 125hz, 200hz, 800hz, 1.6Khz, 2.0Khz, 2.5Khz, 3.15Khz, 6.3Khz <

You have to take that all with a huge grain of salt. Acoustic interference is the root cause, and a cheap cardioid microphone doesn't help matters. Sine waves are useful mainly at low frequencies, but pink noise makes more sense at the higher range. Without a better way to measure, I'd basically ignore all those readings and just accept that your room has problems.

> given the bad room mode dimensions of my entire basement would I get any benefit from hanging 4" 703 in the corners? <

Yes! The worse the room, the more it needs bass trapping. Not the other way around.

--Ethan