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Discussion Starter · #1 ·
Hi Guys/Gals,

First let me start by saying this site is amazing. I am so happy to have found this community. I can't believe REW is free. :sn:

I just moved into a new house and have been setting up my room. Here it is, less than ideal. Here are the responses from 3 different positions in my room. I am using Adam A7s + Sub10, and the radioshack SPL 33-4050 to measure the sound.

Is all hope lost? :nerd: Any suggestions?

-Matthew
 

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First let me start by saying this site is amazing. I am so happy to have found this community. I can't believe REW is free. :sn:
It has to be one of the best deals on the planet, does it not? I have used numerous other audio analysis tools, and REW's capabilities shine in comparison to tools that cost hundreds of dollars. I, too, am continually impressed by the program, the responsiveness of the author - good old John M, who answers posts personally almost every day, the frequency of updates... All free. Glad you are enjoying it.

Here are the responses from 3 different positions in my room. I am using Adam A7s + Sub10, and the radioshack SPL 33-4050 to measure the sound.
Nice start. As Phillips suggested, to get serious about your audio work you will need a calibrated SPL meter or measurement mic. But you can get a rough idea what is going on in your room with an uncalibrated SPL meter. Your posted plots indicate there is probably work to be done, but we could use some more info. Perhaps you could sketch in the speaker positions and the furniture showing the primary listening position (PLP). Then show us your measurements from the PLP perspective, those are the main ones you will work with going forward.

Keep having fun!

And welcome to Home Theater Shack! We are glad to have you aboard!
 

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Welcome and thanks for joining us! Please visit us often.

Do you have flexibility to add acoustic treatments to the room? By that I mean is the room dedicated to home theater or is it multi functional? Treatments can be made to look somewhat attractive, but you will know that they are there.

Treatments include bass traps and side wall absorption. Bass traps will smooth out the frequency response from about 6o Hz to around 150 Hz or so. They also make the bass sound more distinct - such as a bass drum or kick drum. With traps, there will be less reverberant sound making each drum hit more distinct. Side wall absorption can make the left/right imaging seem wider. Check out our Home Audio Acoustic forum for ideas.
 

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Discussion Starter · #6 ·
New graphs will be posted to standard.

The room is my studio for mixing, so no need for aesthetics here... only accurate sound matters. I have mixing desk and a large couch that can be placed anywhere in the room.

Also please label your measurements or describe which is what.
The measurements (1, 2, and 3) are in order as such. The mixing desk and couch where moved to the labeled location. I've attached another photo that's hopefully more clear.

Is your SPL meter calibrated?
I am using the Radioshack Model 33-4050 calibration file provided on the download page: http://www.hometheatershack.com/forums/downloads-area/19-downloads-page.html
Would you recommend a manual calibration?

Treatments include bass traps and side wall absorption.
I have the Auralex room kit, which
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includes 8 bass traps, diffusors and absorbers. I'm thinking it might not be enough.
http://www.auralex.com/sound_control_deluxeplus/sound_control_deluxeplus.asp

Here is the room.
Text Diagram



:hsd::paddle::rofl::help::rolleyesno::coocoo::rant::devil::unbelievable::doh::D
 

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... only accurate sound matters.
This does matter then, the SPL meter will give you an idea but you want accuracy then get a calibrated Mic with a calibration file e.g TXT, FRD to load into REW.

Both are supplied by Cross-Spectrum
1. You can go down the convenience road with a USB mic e.g UMIK-1 or Dayton UMM-6 so you use the laptops soundcard e.g. headphones out or HDMI. NO SOUNDCARD CALIBRATION DONE.

2. Other is Pre/Soundcard (which you might have already) that is connected to a Mic e.g. DAyton EMM-6 (requiires phantom power). I don't think Cross-Spectrum has Pre Soundcards. This option gives you the opportunity to do more e.g. Loopback for timing.

Hope this helps.
 

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I am using the Radioshack Model 33-4050 calibration file provided on the download page: http://www.hometheatershack.com/forums/downloads-area/19-downloads-page.html
Would you recommend a manual calibration?
Generic calibration files are a step in the right direction, but for serious audio work there is still a lot of potential error. A mic with an individual calibration file is a must, then you have known accuracy to work with. Calibrated USB SPL meters can be found, too, but a mic will actually be cheaper and provide all the same function in conjunction with your computer. I would go with the calibrated mic.
 

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Discussion Starter · #11 ·
but you want accuracy then get a calibrated Mic with a calibration file
Agreed, I think this is the most logical next step. @Phillips, can you suggest a good calibrated mic to get. I could spend $100 - $200. Would it come pre-calibrated?

Can you move your set-up to location 1, place the sub at the midpoint of that wall and spread your speakers 3.5 ft to ether side of the sub, and re-measure?
@sdurani, I actually found this spot to have the best stereo imaging and least early reflections. The problem, though, was the massive null at 71Hz. It was super audible, I could barely hear it with a tone test.:crying:

The sub was placed under the mixing desk, which was at the midpoint of the wall. Speakers are also 3.5ft apart. I didn't think about this, but maybe I need to move it somewhere else in the room...? I'm starting to realize this is a bit of black magic!

Do I just need to buy a lot of bass traps?
 

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Agreed, I think this is the most logical next step. @Phillips, can you suggest a good calibrated mic to get. I could spend $100 - $200. Would it come pre-calibrated?
Matter of fact other than getting use to REW i would stop right there, you could be tempted to make changes where not necessarily applicable.

XLR mic coupled with Pre/Soundcard (Phantom Power)
1. Dayton EMM-6 with a Tascam MKII (people seem to find these very god for the money).

USB mic using the laptops soundcard
1. MiniDSP UMIK-1
2. Dayton UMM-6 (Herb seems to be having a problem see this link http://www.hometheatershack.com/for...s/63440-new-dayton-audio-umm-6-usb-mic-8.html

All of these are supplied (except for the Tascam) with a mic calibration file (ACCURATE) and best thing of all great service from Cross - Spectrum. see his thread. Click on this link http://www.hometheatershack.com/for...ctrum-microphone-calibration-service-usa.html

What O/S are you using?
 
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