Home Theater Systems - Electronics and Forum - HomeTheaterShack - REW Forum http://www.hometheatershack.com/forums/ REW is Room EQ Wizard... an extremely popular and accurate application for measuring room responses and correcting modal resonances. Learn how to setup and use this famous room eq software. This is the forum to share and discuss your response measurement and waterfall graphs. Moderators: brucek, glaufman, JohnM, Wayne A. Pflughaupt REW Online Help File en Sun, 22 Nov 2009 10:39:32 GMT vBulletin 60 http://www.hometheatershack.com/forums/images/misc/rss.jpg Home Theater Systems - Electronics and Forum - HomeTheaterShack - REW Forum http://www.hometheatershack.com/forums/ Measuring a crossed over speaker, near-field distance http://www.hometheatershack.com/forums/rew-forum/23086-measuring-crossed-over-speaker-near-field-distance.html Sun, 22 Nov 2009 01:59:55 GMT Hello, I was wondering if anyone had any experience measuring near-field responses of speakers that are crossed over... I... Hello, I was wondering if anyone had any experience measuring near-field responses of speakers that are crossed over... I realize that near the crossover frequency there will be issues like constructive/destructive interference, especially with non-coaxial speakers; if anyone has a system (with a good reason behind it) for the distance or placement (centered on the tweeter, mid-bass, etc.) please let me know :)

Currently I measure crossed over speakers with the tweeter on-axis, 6" out from the front of the baffle. ]]> REW Forum Chester http://www.hometheatershack.com/forums/rew-forum/23086-measuring-crossed-over-speaker-near-field-distance.html first measurements!!! help wanted and needed http://www.hometheatershack.com/forums/rew-forum/23078-first-measurements-help-wanted-needed.html Sat, 21 Nov 2009 21:56:14 GMT hi all, im equalizing my sub using a dcx2496(also lowpass) , and its doing a fairly good job.
my room some "small" problems, concrete building and minemalistic decoration....

my concern is music, no ht duty!

my sub is a passive 12 dvc dual voice core unit, driven by both channels from a nakamichi pa-5s2 that suplies around 2x 490Watts in 2ohm, so i should have some head room to spare....


here is what i gott to work with: rew measurements with no eq or sub crossover filters aplied yet.

first is :frontspeakers only:
second is: sub only
third is: front and sub(no eq or lowpass)


what would you recommend, how do i attack that curve?

best regards

panduro

first is :frontspeakers only:
second is: sub only
third is: front and sub(no eq or lowpass)
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]]> REW Forum panduro http://www.hometheatershack.com/forums/rew-forum/23078-first-measurements-help-wanted-needed.html <![CDATA[first measure and What's next ???]]> http://www.hometheatershack.com/forums/rew-forum/23066-first-measure-whats-next.html Sat, 21 Nov 2009 13:15:38 GMT Hi,

It's my first post here. Recently I bought new monitors for my studio - PMC TB2.
I use them in my post production studio, mainly mix and master. Studio is well trapped (not professionally, though, all by myself). It has a rather 'rare' shape, being a rectangle with cut in one corner.
Until a week ago I setup my speakers using my ears mostly, basic knowledge and explored best options (knowing my room limitations). Actually I was quite happy with achievements.

Since PMC's situation has change I decided to check acoustics of room properly. So I bought SPL from radioshack and downloaded REW. I managed to calibrate my audiointerface, SPL meter and make first measurements.
I don't have a clue how to interpret those data. I played a bit with speaker setup, moving them in all directions, noticed that graph with data has changed.
Anyway I feel like a blind man, not understanding what I am actually doing.
My goal is to get room EQ as best as possible. i understand it's not only speaker setup, but mostly room and room treatment.
So my question is, what is really wrong with graph below ?
What I should be focused on to achieve best results ?
I spent over 3 days setting up PMC's (very very touchy about placement) and I thought I 've found sweet spot. Then after measures with SPL, I am confused ....

I got dozens of questions, starting from - should I seat in my chair (mixing/listening position) and then start measure, or should I leave the room ? etc, etc.

I hope you guys will help me !

thanx in advance

PS sorry for a photo format... I just made photo off my oder PC (in studio) ...faster option.

]]> REW Forum tresperros http://www.hometheatershack.com/forums/rew-forum/23066-first-measure-whats-next.html <![CDATA[What's wrong with this?]]> http://www.hometheatershack.com/forums/rew-forum/23048-whats-wrong.html Fri, 20 Nov 2009 18:33:32 GMT I did a near field measurement of my Peerless 12"xls and got this. It dosen't look right. Am I doing something wrong? YTommyD
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]]> REW Forum Tommy D http://www.hometheatershack.com/forums/rew-forum/23048-whats-wrong.html Calibrating Mic Preamp http://www.hometheatershack.com/forums/rew-forum/23014-calibrating-mic-preamp.html Thu, 19 Nov 2009 18:56:49 GMT I have run REW measurements with the RS Meter plugged into my sound card and all was well. I ran with my soundcard and... I have run REW measurements with the RS Meter plugged into my sound card and all was well. I ran with my soundcard and someone elses mic and mic preamp/mixer, and all was well. Someone else measured the room previously (diferent software and hardeare) and the results matched those results I got. When I run with two different mics into my mic preamp (Rane), they each get the same result but different results from the other three about 50Hz down. From 50Hz down to 10Hz the FR drops to about 10db below the other three.

Could this be a mic-preamp issue (or maybe an operator issue).Is there a way to calibrate my mic preamp? ]]> REW Forum Audioguy http://www.hometheatershack.com/forums/rew-forum/23014-calibrating-mic-preamp.html First REW graph, help http://www.hometheatershack.com/forums/rew-forum/23009-first-rew-graph-help.html Thu, 19 Nov 2009 16:03:29 GMT Hello,

I have had REW and a usb soundcard for some time but am intimidated by the program.
I've just gone thru and calibrated my soundcard, checked and adjusted levels, then calibrated my analog RS meter.

What do you make of my graph? There seem like there are so many variables I could have messed up when calibrating I'm unsure if my graph is valid.My analisis is that it looks decent but starts to drop off around 40 hz.
This could be due to the corner placement or my sub or could have to do with me incorrectly calibrating my soundcard or radioshack meter.
Any imput would be greatly appreciated This graph is pulled from the "measured" tab

]]> REW Forum Gelinas http://www.hometheatershack.com/forums/rew-forum/23009-first-rew-graph-help.html How do I measure Group Delay? http://www.hometheatershack.com/forums/rew-forum/23003-how-do-i-measure-group-delay.html Thu, 19 Nov 2009 06:10:56 GMT .. with REW? .. with REW? ]]> REW Forum michael123 http://www.hometheatershack.com/forums/rew-forum/23003-how-do-i-measure-group-delay.html Another Level Question (Newbie) http://www.hometheatershack.com/forums/rew-forum/22971-another-level-question-newbie.html Wed, 18 Nov 2009 03:24:32 GMT Hi Everyone,

I'm working my way through the steps to use REW, and I've run into something that I don't understand. Here's a summary of where I'm at:

1) I have a Creative Labs "Blaster X-fi" external sound card. This card has separate right and left channels for line out. It has a single connector for line in.

2) I'm using a Radio Shack digital SPL meter.

I believe I have done the sound card calibration properly. I set up the cables as shown in the first attachment.

On this picture, I ran the right line output from the sound card to the right side of the splitter plugged into the sound card's line in. I believe that this Radio Shack Connector splits out left and right signals from the single pin. The picture shows a second splitter which is identical to the one plugged into the sound card for reference.

The second attachment is the sound card's uncorrected response. The corrected response is completely flat from 2 - 24Khz. I don't have a jpeg for this graph.

So am I on track as far as the setup and procedures for calibrating the sound card ?

I think I have done all of the steps correctly, but when I go to the acutal measurment phase of the process, I'm running into something I don't understand, so I thought it's possible that I've done something wrong with these steps, and would be best to check.

Measurement Phase:

My thought was that I would measure the subwoofer first on its own without involving the mains. My sub has a separate amplifier with line in connectors for signal, and a separate output level control. For REW, I took the Right Output from the sound card's line out and ran it into the sub's line in, and ran the SPL's output into the same right side connector that I used for the sound card calibration.

3) I ran the sound meter calibration procedure as described in the help files. For this, I played the subwoofer test tone, and set the numeric value on REW to match what was shown on my SPL meter. I adjusted the output at the sub's amp so that it read 75 db.

4) Next I did a measurment. This is where I don't understand something.

5) I clicked on the measurement icon, set the start Freq to 15 HZ, and the End Freq. to 200 Hz. When I pressed the "check levels" button, I get a message that says "Level is Low". I'm not sure what level this message is referring to. Is it the output from the Line Out right channel, or is is the output from the sub that is low, or is it something else ?

I was able to set the Level (dB FS) setting to make this message to go away. But when I did this, the measurements were all above the recommended 75 dB level. I don't seem able to find the right combination to make the "Level is Low" message go away while at the same time keeping the measured output at 75 dB. If anyone has any words of wisdom, I'd greatly appreciate it.

Thanks In Advance :)

Rog
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]]> REW Forum rogerv http://www.hometheatershack.com/forums/rew-forum/22971-another-level-question-newbie.html Volume too loud during sweep http://www.hometheatershack.com/forums/rew-forum/22970-volume-too-loud-during-sweep.html Wed, 18 Nov 2009 01:50:56 GMT I have been using REW for a few years now and I am embassed to ask this but I can't figure this out. I know is a simple solution but..
What is happening is I left my SPL meter on and drained the battery so I replaced it with a new one.
When I went to do a new measurement I did the calibration to 75db first but when I did a sweep the volume was so loud well about the 75db set during calibration. The clipping message came up and the graph was in the high 80's.
I leveled the sound card again and have it set according to the program -18 output, -12db left and right. callibrates for main speakers. I'm using speaker out and line-in.
It's connected to my pre amp and the volume is set there to read 75 db on the radio shack meter.

so what going wrong Help! ]]> REW Forum jpv http://www.hometheatershack.com/forums/rew-forum/22970-volume-too-loud-during-sweep.html <![CDATA[Please help me get started >>>]]> http://www.hometheatershack.com/forums/rew-forum/22958-please-help-me-get-started.html Tue, 17 Nov 2009 14:34:05 GMT I have been posting on AVSforums for a couple of years, and I was punted here for enlightenment. I recently upgraded from a... I have been posting on AVSforums for a couple of years, and I was punted here for enlightenment. I recently upgraded from a 10" Velodyne DLS-3750 to a SVS PC12-PLUS. I was on the verge of returning the PC12+ when I decided to give this PEQ stuff a try.

What and WHERE do I need to go to buy the stuff needed to get my sub calibrated for hopefully less than $200. I already have a new RatShack SPL meter. Thanks! BTW, I have seen the links to the REW page. ]]> REW Forum deepstang http://www.hometheatershack.com/forums/rew-forum/22958-please-help-me-get-started.html Calibration of Firepod causes problem http://www.hometheatershack.com/forums/rew-forum/22957-calibration-firepod-causes-problem.html Tue, 17 Nov 2009 10:56:34 GMT Hi there, I used REW before on a PC based system at a friends studio and everything went fine. Im currently in the... Hi there,

I used REW before on a PC based system at a friends studio and everything went fine.
Im currently in the process of setting up a different studio which is mac based (Leopard 10.5).
We are restricted to a Presonus Firepod at the moment but I thought that should be a problem. However, when calibrating the soundcard a few problems occur:

1) A direct loop from line out to line in results in a loss of almost 10dB (cable is fine) which has to be compensated using the line trim

2) The result of the calibration looks quite odd and I wonder where the problem might be (see screenshots). This cant be right.

Can anyone give me a hint where the problem might be? I tried the calibration with and without using the line trim with the same results.

Any help is appreciated.

thank you
studiomann
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]]> REW Forum studiomann http://www.hometheatershack.com/forums/rew-forum/22957-calibration-firepod-causes-problem.html <![CDATA[Lil' help]]> http://www.hometheatershack.com/forums/rew-forum/22944-lil-help.html Mon, 16 Nov 2009 23:55:37 GMT May I have a few recommendations for a external sound card to purchase for my VGN-FW235J (64bit). I understand that I can't use just any one.
I'm looking forward to downloading REW and getting started. I'm trying to put the right tools in place for the job. ]]> REW Forum hfhe http://www.hometheatershack.com/forums/rew-forum/22944-lil-help.html Setting up levels in rew http://www.hometheatershack.com/forums/rew-forum/22931-setting-up-levels-rew.html Mon, 16 Nov 2009 14:07:44 GMT Hi there, Can anyone give me a step by step guide in setting up the levels for REW before doing measurements. I have read... Hi there,

Can anyone give me a step by step guide in setting up the levels for REW before doing measurements. I have read the REW online help over and over again but no matter what I do I can never get the levels correct. I am using a Turtle ARM external sound card in vista. I can calibrate the soundcard no problem although I have to much around with the soundcard's volume settings a bit but I do get that done.

I then go to check levels for the subwoofer and they are really low and even with the input volume on max and the onkyo on -15db it is still reading -30db which is too low.

I would appreciate some guidance please so if someone could break it down in simplist terms that would be great.

cheers

graham ]]> REW Forum gperkins_1973 http://www.hometheatershack.com/forums/rew-forum/22931-setting-up-levels-rew.html HP DV7 Laptop Mic http://www.hometheatershack.com/forums/rew-forum/22896-hp-dv7-laptop-mic.html Sun, 15 Nov 2009 06:54:41 GMT Can I use my DV7 HP Laptop's Mic to run Rew? It needs not to be perfect, just for a comparison from one sub to the next.

Thanks. ]]> REW Forum davidburn http://www.hometheatershack.com/forums/rew-forum/22896-hp-dv7-laptop-mic.html Please Review First-timer Graph??? http://www.hometheatershack.com/forums/rew-forum/22890-please-review-first-timer-graph.html Sun, 15 Nov 2009 04:29:26 GMT Hello, The following is a graph taken using REW. I am using a SVS SB12PLUS with a crossover at 80HZ. Main speakers are... Hello,

The following is a graph taken using REW. I am using a SVS SB12PLUS with a crossover at 80HZ. Main speakers are disconnected. Loaded correct Radio Shack Meter calibration and completed soundcard calibration which looked good (using Behringer UC 202). I check my AVR and made sure it was setup in stereo and all DSP/boosts/trims are shut off. I feel I followed all of the directions and need some additional advice. Thanks in advance for you input.

Why is the sub db level significantly higher than my target 75 db which was setup? It appears to following the curve at a higher db level.
What are your thoughts regarding the graph? I know I can play around with sub placement a bit? I also can smooth out the null a bit 27HZ by increasing the crossover to 100HZ on my AVR.
It also appears I have some noise in my PC soundcard with the steep increase at 18HZ after sub rolloff begins. Is this the case based on your experience?
Based on the graph...Is there a specific peak I should tame with my subs PEQ before running audyssey to further smooth out the response?

Attachment 17238
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]]> REW Forum jstatuto http://www.hometheatershack.com/forums/rew-forum/22890-please-review-first-timer-graph.html